fix

lazy applications

.github/workflows/get-example-changed.yml

@@ -24,7 +24,7 @@ jobs:
           fetch-depth: 0
       - name: Get example files that changed
         id: changed-files
-        uses: tj-actions/changed-files@v46
+        uses: tj-actions/changed-files@v47
         with:
           files: |
             examples/**

.github/workflows/get-leptos-changed.yml

@@ -18,7 +18,7 @@ jobs:
           fetch-depth: 0
       - name: Get source files that changed
         id: changed-source
-        uses: tj-actions/changed-files@v46
+        uses: tj-actions/changed-files@v47
         with:
           files_ignore: |
             .*/**/*

.github/workflows/run-cargo-make-task.yml

@@ -88,7 +88,7 @@ jobs:
         run: trunk --version
       - name: Install Node.js
         if: contains(inputs.directory, 'examples')
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: 20
       - uses: pnpm/action-setup@v4

Cargo.toml

@@ -45,44 +45,42 @@ rust-version = "1.88"
 
 [workspace.dependencies]
 # members
-throw_error = { path = "./any_error/", version = "0.3.0" }
+throw_error = { path = "./any_error/", version = "0.3.1" }
 any_spawner = { path = "./any_spawner/", version = "0.3.0" }
 const_str_slice_concat = { path = "./const_str_slice_concat", version = "0.1" }
 either_of = { path = "./either_of/", version = "0.1.6" }
 hydration_context = { path = "./hydration_context", version = "0.3.0" }
-leptos = { path = "./leptos", version = "0.8.8" }
+leptos = { path = "./leptos", version = "0.8.12" }
 leptos_config = { path = "./leptos_config", version = "0.8.7" }
-leptos_dom = { path = "./leptos_dom", version = "0.8.6" }
+leptos_dom = { path = "./leptos_dom", version = "0.8.7" }
 leptos_hot_reload = { path = "./leptos_hot_reload", version = "0.8.5" }
-leptos_integration_utils = { path = "./integrations/utils", version = "0.8.5" }
-leptos_macro = { path = "./leptos_macro", version = "0.8.8" }
-leptos_router = { path = "./router", version = "0.8.6" }
-leptos_router_macro = { path = "./router_macro", version = "0.8.5" }
+leptos_integration_utils = { path = "./integrations/utils", version = "0.8.6" }
+leptos_macro = { path = "./leptos_macro", version = "0.8.11" }
+leptos_router = { path = "./router", version = "0.8.9" }
+leptos_router_macro = { path = "./router_macro", version = "0.8.6" }
 leptos_server = { path = "./leptos_server", version = "0.8.5" }
 leptos_meta = { path = "./meta", version = "0.8.5" }
 next_tuple = { path = "./next_tuple", version = "0.1.0" }
 oco_ref = { path = "./oco", version = "0.2.1" }
 or_poisoned = { path = "./or_poisoned", version = "0.1.0" }
-reactive_graph = { path = "./reactive_graph", version = "0.2.6" }
-reactive_stores = { path = "./reactive_stores", version = "0.2.5" }
+reactive_graph = { path = "./reactive_graph", version = "0.2.9" }
+reactive_stores = { path = "./reactive_stores", version = "0.3.0" }
 reactive_stores_macro = { path = "./reactive_stores_macro", version = "0.2.6" }
-server_fn = { path = "./server_fn", version = "0.8.6" }
-server_fn_macro = { path = "./server_fn_macro", version = "0.8.7" }
+server_fn = { path = "./server_fn", version = "0.8.8" }
+server_fn_macro = { path = "./server_fn_macro", version = "0.8.8" }
 server_fn_macro_default = { path = "./server_fn/server_fn_macro_default", version = "0.8.5" }
-tachys = { path = "./tachys", version = "0.2.7" }
-wasm_split_helpers = { path = "./wasm_split", version = "0.1.2" }
-wasm_split_macros = { path = "./wasm_split_macros", version = "0.1.2" }
+tachys = { path = "./tachys", version = "0.2.10" }
 
 # members deps
 async-once-cell = { default-features = false, version = "0.5.3" }
 itertools = { default-features = false, version = "0.14.0" }
 convert_case = { default-features = false, version = "0.8.0" }
-serde_json = { default-features = false, version = "1.0.142" }
+serde_json = { default-features = false, version = "1.0.143" }
 trybuild = { default-features = false, version = "1.0.110" }
-typed-builder = { default-features = false, version = "0.21.0" }
-thiserror = { default-features = false, version = "2.0.12" }
+typed-builder = { default-features = false, version = "0.21.2" }
+thiserror = { default-features = false, version = "2.0.17" }
 wasm-bindgen = { default-features = false, version = "0.2.100" }
-indexmap = { default-features = false, version = "2.9.0" }
+indexmap = { default-features = false, version = "2.11.0" }
 rstml = { default-features = false, version = "0.12.1" }
 rustc_version = { default-features = false, version = "0.4.1" }
 guardian = { default-features = false, version = "1.3.0" }
@@ -97,71 +95,72 @@ send_wrapper = { default-features = false, version = "0.6.0" }
 tokio-test = { default-features = false, version = "0.4.4" }
 html-escape = { default-features = false, version = "0.2.13" }
 proc-macro-error2 = { default-features = false, version = "2.0.1" }
-const_format = { default-features = false, version = "0.2.34" }
+const_format = { default-features = false, version = "0.2.35" }
 gloo-net = { default-features = false, version = "0.6.0" }
 url = { default-features = false, version = "2.5.4" }
 tokio = { default-features = false, version = "1.47.1" }
 base64 = { default-features = false, version = "0.22.1" }
-cfg-if = { default-features = false, version = "1.0.0" }
+cfg-if = { default-features = false, version = "1.0.3" }
 wasm-bindgen-futures = { default-features = false, version = "0.4.50" }
 tower = { default-features = false, version = "0.5.2" }
-proc-macro2 = { default-features = false, version = "1.0.96" }
+proc-macro2 = { default-features = false, version = "1.0.101" }
 serde = { default-features = false, version = "1.0.219" }
-parking_lot = { default-features = false, version = "0.12.4" }
-axum = { default-features = false, version = "0.8.4" }
+parking_lot = { default-features = false, version = "0.12.5" }
+axum = { default-features = false, version = "0.8.6" }
 serde_qs = { default-features = false, version = "0.15.0" }
-syn = { default-features = false, version = "2.0.104" }
+syn = { default-features = false, version = "2.0.106" }
 xxhash-rust = { default-features = false, version = "0.8.15" }
 paste = { default-features = false, version = "1.0.15" }
-quote = { default-features = false, version = "1.0.40" }
+quote = { default-features = false, version = "1.0.41" }
 web-sys = { default-features = false, version = "0.3.77" }
 js-sys = { default-features = false, version = "0.3.77" }
 rand = { default-features = false, version = "0.9.1" }
 serde-lite = { default-features = false, version = "0.5.0" }
-tokio-tungstenite = { default-features = false, version = "0.27.0" }
+tokio-tungstenite = { default-features = false, version = "0.28.0" }
 serial_test = { default-features = false, version = "3.2.0" }
 erased = { default-features = false, version = "0.1.2" }
 glib = { default-features = false, version = "0.20.12" }
-async-trait = { default-features = false, version = "0.1.88" }
+async-trait = { default-features = false, version = "0.1.89" }
 typed-builder-macro = { default-features = false, version = "0.21.0" }
 linear-map = { default-features = false, version = "1.2.0" }
-anyhow = { default-features = false, version = "1.0.98" }
+anyhow = { default-features = false, version = "1.0.100" }
 walkdir = { default-features = false, version = "2.5.0" }
 actix-ws = { default-features = false, version = "0.3.0" }
 tower-http = { default-features = false, version = "0.6.4" }
-prettyplease = { default-features = false, version = "0.2.36" }
-inventory = { default-features = false, version = "0.3.20" }
-config = { default-features = false, version = "0.15.13" }
-camino = { default-features = false, version = "1.1.11" }
+prettyplease = { default-features = false, version = "0.2.37" }
+inventory = { default-features = false, version = "0.3.21" }
+config = { default-features = false, version = "0.15.14" }
+camino = { default-features = false, version = "1.2.1" }
 ciborium = { default-features = false, version = "0.2.2" }
+bitcode = { default-features = false, version = "0.6.6" }
 multer = { default-features = false, version = "3.1.0" }
 leptos-spin-macro = { default-features = false, version = "0.2.0" }
 sledgehammer_utils = { default-features = false, version = "0.3.1" }
 sledgehammer_bindgen = { default-features = false, version = "0.6.0" }
 wasm-streams = { default-features = false, version = "0.4.2" }
-rkyv = { default-features = false, version = "0.8.11" }
+rkyv = { default-features = false, version = "0.8.12" }
 temp-env = { default-features = false, version = "0.3.6" }
 uuid = { default-features = false, version = "1.18.0" }
 bytes = { default-features = false, version = "1.10.1" }
 http = { default-features = false, version = "1.3.1" }
-regex = { default-features = false, version = "1.11.1" }
+regex = { default-features = false, version = "1.11.3" }
 drain_filter_polyfill = { default-features = false, version = "0.1.3" }
-tempfile = { default-features = false, version = "3.20.0" }
+tempfile = { default-features = false, version = "3.23.0" }
 futures-lite = { default-features = false, version = "2.6.1" }
 log = { default-features = false, version = "0.4.27" }
-percent-encoding = { default-features = false, version = "2.3.1" }
+percent-encoding = { default-features = false, version = "2.3.2" }
 async-executor = { default-features = false, version = "1.13.2" }
 const-str = { default-features = false, version = "0.6.4" }
 http-body-util = { default-features = false, version = "0.1.3" }
-hyper = { default-features = false, version = "1.6.0" }
+hyper = { default-features = false, version = "1.7.0" }
 postcard = { default-features = false, version = "1.1.3" }
 rmp-serde = { default-features = false, version = "1.3.0" }
-reqwest = { default-features = false, version = "0.12.22" }
+reqwest = { default-features = false, version = "0.12.23" }
 tower-layer = { default-features = false, version = "0.3.3" }
-attribute-derive = { default-features = false, version = "0.10.3" }
+attribute-derive = { default-features = false, version = "0.10.5" }
 insta = { default-features = false, version = "1.43.1" }
 codee = { default-features = false, version = "0.3.0" }
-actix-http = { default-features = false, version = "3.11.0" }
+actix-http = { default-features = false, version = "3.11.2" }
 wasm-bindgen-test = { default-features = false, version = "0.3.50" }
 rustversion = { default-features = false, version = "1.0.22" }
 getrandom = { default-features = false, version = "0.3.3" }
@@ -170,6 +169,10 @@ async-lock = { default-features = false, version = "3.4.1" }
 base16 = { default-features = false, version = "0.2.1" }
 digest = { default-features = false, version = "0.10.7" }
 sha2 = { default-features = false, version = "0.10.8" }
+subsecond = { default-features = false, version = "0.7.0-rc.0" }
+dioxus-cli-config = { default-features = false, version = "0.7.0-rc.0" }
+dioxus-devtools = { default-features = false, version = "0.7.0-rc.0" }
+wasm_split_helpers = { default-features = false, version = "0.2.0" }
 
 [profile.release]
 codegen-units = 1

README.md

@@ -95,7 +95,7 @@ Here are some resources for learning more about Leptos:
 [`cargo-leptos`](https://github.com/leptos-rs/cargo-leptos) is a build tool that's designed to make it easy to build apps that run on both the client and the server, with seamless integration. The best way to get started with a real Leptos project right now is to use `cargo-leptos` and our starter templates for [Actix](https://github.com/leptos-rs/start) or [Axum](https://github.com/leptos-rs/start-axum).
 
 ```bash
-cargo install cargo-leptos
+cargo install cargo-leptos --locked
 cargo leptos new --git https://github.com/leptos-rs/start-axum
 cd [your project name]
 cargo leptos watch

any_error/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "throw_error"
-version = "0.3.0"
+version = "0.3.1"
 authors = ["Greg Johnston"]
 license = "MIT"
 readme = "../README.md"
@@ -11,3 +11,6 @@ edition.workspace = true
 
 [dependencies]
 pin-project-lite = { workspace = true, default-features = true }
+
+[dev-dependencies]
+anyhow.workspace = true

any_error/src/lib.rs

@@ -45,10 +45,10 @@ impl fmt::Display for Error {
 
 impl<T> From<T> for Error
 where
-    T: error::Error + Send + Sync + 'static,
+    T: Into<Box<dyn error::Error + Send + Sync + 'static>>,
 {
     fn from(value: T) -> Self {
-        Error(Arc::new(value))
+        Error(Arc::from(value.into()))
     }
 }
 
@@ -158,3 +158,32 @@ where
         this.inner.poll(cx)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::error::Error as StdError;
+
+    #[derive(Debug)]
+    struct MyError;
+
+    impl Display for MyError {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            write!(f, "MyError")
+        }
+    }
+
+    impl StdError for MyError {}
+
+    #[test]
+    fn test_from() {
+        let e = MyError;
+        let _le = Error::from(e);
+
+        let e = "some error".to_string();
+        let _le = Error::from(e);
+
+        let e = anyhow::anyhow!("anyhow error");
+        let _le = Error::from(e);
+    }
+}

examples/lazy_routes/Cargo.toml

@@ -10,7 +10,7 @@ crate-type = ["cdylib", "rlib"]
 axum = { version = "0.8.1", optional = true }
 console_error_panic_hook = "0.1.7"
 console_log = "1.0"
-leptos = { path = "../../leptos", features = ["tracing"] }
+leptos = { path = "../../leptos", features = ["tracing", "lazy"] }
 leptos_meta = { path = "../../meta" }
 leptos_axum = { path = "../../integrations/axum", optional = true }
 leptos_router = { path = "../../router" }

examples/regression/e2e/features/issue_4251.feature

@@ -0,0 +1,13 @@
+@check_issue_4251
+Feature: Check that issue 4251 does not reappear
+
+	Scenario: Clicking a link to the same page you’re currently on should not add the page to the history stack.
+		Given I see the app
+		And I can access regression test 4324
+		When I select the link This page
+		And I select the link This page
+		And I select the link This page
+		Then I see the result is the string Issue4324
+		When I press the back button
+		And I select the link 4324
+		Then I see the result is the string Issue4324

examples/regression/e2e/features/issue_4285.feature

@@ -0,0 +1,9 @@
+@check_issue_4285
+Feature: Check that issue 4285 does not reappear
+
+	Scenario: Navigating several times to same lazy route does not cause issues.
+		Given I see the app
+		And I can access regression test 4285
+		And I can access regression test 4285
+		And I can access regression test 4285
+		Then I see the result is the string 42

examples/regression/e2e/features/issue_4296.feature

@@ -0,0 +1,18 @@
+@check_issue_4296
+Feature: Check that issue 4296 does not reappear
+
+	Scenario: Query param signals created in LazyRoute::data() are reactive in ::view().
+		Given I see the app
+		And I can access regression test 4296
+		Then I see the result is the string None
+		When I select the link abc
+		Then I see the result is the string Some("abc")
+		When I select the link def
+		Then I see the result is the string Some("def")
+
+	Scenario: Loading page with query signal works as well.
+		Given I see the app
+		And I can access regression test 4296
+		When I select the link abc
+		When I reload the page
+		Then I see the result is the string Some("abc")

examples/regression/e2e/features/issue_4324.feature

@@ -0,0 +1,11 @@
+@check_issue_4324
+Feature: Check that issue 4324 does not reappear
+
+	Scenario: Navigating to the same page after clicking "Back" should set the URL correctly
+		Given I see the app
+		And I can access regression test 4324
+		Then I see the path is /4324/
+		When I press the back button
+		Then I see the path is /
+		When I select the link 4324
+		Then I see the path is /4324/

examples/regression/e2e/tests/fixtures/check.rs

@@ -43,3 +43,13 @@ pub async fn element_value_is(
     assert_eq!(value.as_deref(), Some(expected));
     Ok(())
 }
+
+pub async fn path_is(client: &Client, expected_path: &str) -> Result<()> {
+    let url = client
+        .current_url()
+        .await
+        .expect("could not access current URL");
+    let path = url.path();
+    assert_eq!(expected_path, path);
+    Ok(())
+}

examples/regression/e2e/tests/fixtures/world/action_steps.rs

@@ -45,3 +45,12 @@ async fn i_refresh_the_browser(world: &mut AppWorld) -> Result<()> {
 
     Ok(())
 }
+
+#[given(regex = "^I press the back button$")]
+#[when(regex = "^I press the back button$")]
+async fn i_go_back(world: &mut AppWorld) -> Result<()> {
+    let client = &world.client;
+    client.back().await?;
+
+    Ok(())
+}

examples/regression/e2e/tests/fixtures/world/check_steps.rs

@@ -43,3 +43,10 @@ async fn i_see_the_value(
     check::element_value_is(client, &id, &value).await?;
     Ok(())
 }
+
+#[then(regex = r"^I see the path is (.*)$")]
+async fn i_see_the_path(world: &mut AppWorld, path: String) -> Result<()> {
+    let client = &world.client;
+    check::path_is(client, &path).await?;
+    Ok(())
+}

examples/regression/src/app.rs

@@ -1,5 +1,6 @@
 use crate::{
     issue_4005::Routes4005, issue_4088::Routes4088, issue_4217::Routes4217,
+    issue_4285::Routes4285, issue_4296::Routes4296, issue_4324::Routes4324,
     pr_4015::Routes4015, pr_4091::Routes4091,
 };
 use leptos::prelude::*;
@@ -31,9 +32,11 @@ pub fn shell(options: LeptosOptions) -> impl IntoView {
 pub fn App() -> impl IntoView {
     provide_meta_context();
     let fallback = || view! { "Page not found." }.into_view();
+    let (_, set_is_routing) = signal(false);
+
     view! {
         <Stylesheet id="leptos" href="/pkg/regression.css"/>
-        <Router>
+        <Router set_is_routing>
             <main>
                 <Routes fallback>
                     <Route path=path!("") view=HomePage/>
@@ -42,6 +45,9 @@ pub fn App() -> impl IntoView {
                     <Routes4088/>
                     <Routes4217/>
                     <Routes4005/>
+                    <Routes4285/>
+                    <Routes4296/>
+                    <Routes4324/>
                 </Routes>
             </main>
         </Router>
@@ -66,6 +72,9 @@ fn HomePage() -> impl IntoView {
                 <li><a href="/4088/">"4088"</a></li>
                 <li><a href="/4217/">"4217"</a></li>
                 <li><a href="/4005/">"4005"</a></li>
+                <li><a href="/4285/">"4285"</a></li>
+                <li><a href="/4296/">"4296"</a></li>
+                <li><a href="/4324/">"4324"</a></li>
             </ul>
         </nav>
     }

examples/regression/src/issue_4285.rs

@@ -0,0 +1,49 @@
+use leptos::prelude::*;
+use leptos_router::LazyRoute;
+#[allow(unused_imports)]
+use leptos_router::{
+    components::Route, path, Lazy, MatchNestedRoutes, NavigateOptions,
+};
+
+#[component]
+pub fn Routes4285() -> impl MatchNestedRoutes + Clone {
+    view! {
+        <Route path=path!("4285") view={Lazy::<Issue4285>::new()}/>
+    }
+    .into_inner()
+}
+
+struct Issue4285 {
+    data: Resource<Result<i32, ServerFnError>>,
+}
+
+impl LazyRoute for Issue4285 {
+    fn data() -> Self {
+        Self {
+            data: Resource::new(|| (), |_| slow_call()),
+        }
+    }
+
+    async fn view(this: Self) -> AnyView {
+        let Issue4285 { data } = this;
+        view! {
+            <Suspense>
+                {move || {
+                    Suspend::new(async move {
+                        let data = data.await;
+                        view! {
+                            <p id="result">{data}</p>
+                        }
+                    })
+                }}
+            </Suspense>
+        }
+        .into_any()
+    }
+}
+
+#[server]
+async fn slow_call() -> Result<i32, ServerFnError> {
+    tokio::time::sleep(std::time::Duration::from_millis(250)).await;
+    Ok(42)
+}

examples/regression/src/issue_4296.rs

@@ -0,0 +1,36 @@
+use leptos::prelude::*;
+#[allow(unused_imports)]
+use leptos_router::{
+    components::Route, path, Lazy, MatchNestedRoutes, NavigateOptions,
+};
+use leptos_router::{hooks::use_query_map, LazyRoute};
+
+#[component]
+pub fn Routes4296() -> impl MatchNestedRoutes + Clone {
+    view! {
+        <Route path=path!("4296") view={Lazy::<Issue4296>::new()}/>
+    }
+    .into_inner()
+}
+
+struct Issue4296 {
+    query: Signal<Option<String>>,
+}
+
+impl LazyRoute for Issue4296 {
+    fn data() -> Self {
+        let query = use_query_map();
+        let query = Signal::derive(move || query.read().get("q"));
+        Self { query }
+    }
+
+    async fn view(this: Self) -> AnyView {
+        let Issue4296 { query } = this;
+        view! {
+            <a href="?q=abc">"abc"</a>
+            <a href="?q=def">"def"</a>
+            <p id="result">{move || format!("{:?}", query.get())}</p>
+        }
+        .into_any()
+    }
+}

examples/regression/src/issue_4324.rs

@@ -0,0 +1,21 @@
+use leptos::prelude::*;
+#[allow(unused_imports)]
+use leptos_router::{
+    components::Route, path, Lazy, MatchNestedRoutes, NavigateOptions,
+};
+
+#[component]
+pub fn Routes4324() -> impl MatchNestedRoutes + Clone {
+    view! {
+        <Route path=path!("4324") view=Issue4324/>
+    }
+    .into_inner()
+}
+
+#[component]
+pub fn Issue4324() -> impl IntoView {
+    view! {
+        <a href="/4324/">"This page"</a>
+        <p id="result">"Issue4324"</p>
+    }
+}

examples/regression/src/lib.rs

@@ -2,6 +2,9 @@ pub mod app;
 mod issue_4005;
 mod issue_4088;
 mod issue_4217;
+mod issue_4285;
+mod issue_4296;
+mod issue_4324;
 mod pr_4015;
 mod pr_4091;
 

examples/server_fns_axum/src/app.rs

@@ -440,7 +440,14 @@ pub fn FileUploadWithProgress() -> impl IntoView {
             let mut entry =
                 FILES.entry(filename.to_string()).or_insert_with(|| {
                     println!("[{filename}]\tinserting channel");
-                    let (tx, rx) = broadcast(128);
+                    // NOTE: this channel capacity is set arbitrarily for this demo code.
+                    // it allows for up to exactly 1048 chunks to be sent, which sets an upper cap
+                    // on upload size (the precise details vary by client)
+                    // in a real system, you will want to create some more reasonable ways of
+                    // sending and sharing notifications
+                    //
+                    // see https://github.com/leptos-rs/leptos/issues/4397 for related discussion
+                    let (tx, rx) = broadcast(1048);
                     File { total: 0, tx, rx }
                 });
             entry.total += len;

examples/subsecond_hot_patch/.gitignore

@@ -0,0 +1,7 @@
+# Generated by Cargo
+# will have compiled files and executables
+/target
+.DS_Store
+
+# These are backup files generated by rustfmt
+**/*.rs.bk

examples/subsecond_hot_patch/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "subsecond_hot_patch"
+version = "0.1.0"
+authors = ["Greg Johnston <greg.johnston@gmail.com>"]
+edition = "2021"
+
+[dependencies]
+leptos = { path = "../../leptos", features = ["csr", "subsecond"] }
+leptos_router = { path = "../../router" }
+
+[features]
+default = ["web"]
+web = []

examples/subsecond_hot_patch/Dioxus.toml

@@ -0,0 +1,21 @@
+[application]
+
+[web.app]
+
+# HTML title tag content
+title = "ltest"
+
+# include `assets` in web platform
+[web.resource]
+
+# Additional CSS style files
+style = []
+
+# Additional JavaScript files
+script = []
+
+[web.resource.dev]
+
+# Javascript code file
+# serve: [dev-server] only
+script = []

examples/subsecond_hot_patch/Makefile.toml

@@ -0,0 +1 @@
+extend = [{ path = "../cargo-make/main.toml" }]

examples/subsecond_hot_patch/README.md

@@ -0,0 +1,31 @@
+# Hot Patching with `dx`
+
+This is an experimental example exploring how to combine Leptos with the binary hot-patching provided by Dioxus's `subsecond` library and `dx` cli.
+
+### Serving Your App
+
+This requires installing the Dioxus CLI version 0.7.0. At the time I'm writing this README, that does not yet have a stable release. Once `dioxus-cli` 0.7.0 has been released, you should use the latest stable release. Until then, I'd suggest installing from git:
+
+```sh
+cargo install dioxus-cli --git https://github.com/DioxusLabs/dioxus
+```
+
+Then you can run the example with `dx serve --hot-patch --platform web`.
+
+### Hot Patching
+
+Changes to the your application should be reflected in your app without a full rebuild and reload.
+
+### Limitatations
+
+Currently we only support hot-patching for reactive view functions. You probably want to use `AnyView` (via `.into_any()`) on any views that will be hot-patched, so they can be rebuilt correctly despite their types changing when the structure of the view tree changes.
+
+If you are using `leptos_router` this actually works quite well, as every route’s view is erased to `AnyView` and the router itself is a reactive view function: in other words, changes inside any route should be hot-patched in any case.
+
+Note that any hot-patch will cause all render effects to run again. This means that some client-side state (like the values of signals) will be wiped out.
+
+### Build Tooling
+
+The preference of the Dioxus team is that all hot-patching work that uses their `subsecond` also use `dioxus-cli`. As this demo shows, it's completely possible to use `dioxus-cli` to build and run a Leptos project. We do not plan to build `subsecond` into our own build tooling at this time.
+
+**This is an experiment/POC. It is being published because members of the community have found it useful and have asked for the support to be merged in its current state. Further development and bugfixes are a relatively low priority at this time.**

examples/subsecond_hot_patch/assets/main.css

@@ -0,0 +1,46 @@
+/* App-wide styling */
+body {
+    background-color: #0f1116;
+    color: #ffffff;
+    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
+    margin: 20px;
+}
+
+#hero {
+    margin: 0;
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    align-items: center;
+}
+
+#links {
+    width: 400px;
+    text-align: left;
+    font-size: x-large;
+    color: white;
+    display: flex;
+    flex-direction: column;
+}
+
+#links a {
+    color: white;
+    text-decoration: none;
+    margin-top: 20px;
+    margin: 10px 0px;
+    border: white 1px solid;
+    border-radius: 5px;
+    padding: 10px;
+}
+
+#links a:hover {
+    background-color: #1f1f1f;
+    cursor: pointer;
+}
+
+#header {
+    max-width: 1200px;
+}
+
+
+

examples/subsecond_hot_patch/src/main.rs

@@ -0,0 +1,44 @@
+use leptos::{prelude::*, subsecond::connect_to_hot_patch_messages};
+use leptos_router::{
+    components::{Route, Router, Routes},
+    path,
+};
+
+fn main() {
+    // connect to DX CLI and patch the WASM binary whenever we receive a message
+    connect_to_hot_patch_messages();
+
+    // wrapping App here in a closure so we can hot-reload it, because we only do that
+    // for reactive views right now. changing anything will re-run App and update the view
+    mount_to_body(|| App);
+}
+
+#[component]
+fn App() -> impl IntoView {
+    view! {
+        <nav>
+            <a href="/">"Home"</a>
+            <a href="/about">"About"</a>
+        </nav>
+        <Router>
+            <Routes fallback=|| "Not found">
+                <Route path=path!("/") view=HomePage/>
+                <Route path=path!("/about") view=About/>
+            </Routes>
+        </Router>
+    }
+}
+
+#[component]
+fn HomePage() -> impl IntoView {
+    view! {
+        <h1>"Home Page"</h1>
+    }
+}
+
+#[component]
+fn About() -> impl IntoView {
+    view! {
+        <h1>"About"</h1>
+    }
+}

examples/tailwind_csr/Trunk.toml

@@ -0,0 +1,3 @@
+[tools]
+tailwindcss = "4.1.13"
+

integrations/actix/Cargo.toml

@@ -4,7 +4,7 @@ authors = ["Greg Johnston"]
 license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"
 description = "Actix integrations for the Leptos web framework."
-version = "0.8.5"
+version = "0.8.6"
 rust-version.workspace = true
 edition.workspace = true
 

integrations/utils/Cargo.toml

@@ -4,7 +4,7 @@ authors = ["Greg Johnston"]
 license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"
 description = "Utilities to help build server integrations for the Leptos web framework."
-version = "0.8.5"
+version = "0.8.6"
 rust-version.workspace = true
 edition.workspace = true
 

integrations/utils/src/lib.rs

@@ -68,7 +68,8 @@ pub trait ExtendResponse: Sized {
                 let nonce =
                     use_nonce().map(|n| n.to_string()).unwrap_or_default();
                 if let Some(manifest) = use_context::<WasmSplitManifest>() {
-                    let (pkg_path, manifest) = &*manifest.0.read_value();
+                    let (pkg_path, manifest, wasm_split_file) =
+                        &*manifest.0.read_value();
                     let prefetches = prefetches.0.read_value();
 
                     let all_prefetches = prefetches.iter().flat_map(|key| {
@@ -90,7 +91,7 @@ pub trait ExtendResponse: Sized {
                         .to_html();
                     }
                     _ = view! {
-                        <Link rel="modulepreload" href=format!("{pkg_path}/__wasm_split.js") crossorigin=nonce/>
+                        <Link rel="modulepreload" href=format!("{pkg_path}/{wasm_split_file}") crossorigin=nonce/>
                     }
                     .to_html();
                 }
@@ -120,7 +121,7 @@ pub trait ExtendResponse: Sized {
                     // drop the owner, cleaning up the reactive runtime,
                     // once the stream is over
                     .chain(once(async move {
-                        owner.unset();
+                        owner.unset_with_forced_cleanup();
                         Default::default()
                     })),
             ));

leptos/Cargo.toml

@@ -1,9 +1,10 @@
 [package]
 name = "leptos"
-version = "0.8.8"
+version = "0.8.12"
 authors = ["Greg Johnston"]
 license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"
+homepage = "https://leptos.dev/"
 description = "Leptos is a full-stack, isomorphic Rust web framework leveraging fine-grained reactivity to build declarative user interfaces."
 readme = "../README.md"
 rust-version.workspace = true
@@ -57,7 +58,10 @@ serde_qs = { workspace = true, default-features = true }
 slotmap = { workspace = true, default-features = true }
 futures = { workspace = true, default-features = true }
 send_wrapper = { workspace = true, default-features = true }
-wasm_split_helpers.workspace = true
+wasm_split_helpers = { workspace = true, default-features = true }
+subsecond = { workspace = true, default-features = true, optional = true }
+dioxus-cli-config = { workspace = true, default-features = true, optional = true }
+dioxus-devtools = { workspace = true, default-features = true, optional = true }
 
 [features]
 hydration = [
@@ -85,6 +89,12 @@ ssr = [
 ]
 nightly = ["leptos_macro/nightly", "reactive_graph/nightly", "tachys/nightly"]
 rkyv = ["server_fn/rkyv", "leptos_server/rkyv"]
+bitcode = ["server_fn/bitcode"]
+serde-lite = ["server_fn/serde-lite", "leptos_server/serde-lite"]
+cbor = ["server_fn/cbor"]
+msgpack = ["server_fn/msgpack"]
+postcard = ["server_fn/postcard"]
+multipart = ["server_fn/multipart"]
 tracing = [
   "dep:tracing",
   "reactive_graph/tracing",
@@ -102,6 +112,17 @@ trace-component-props = [
 ]
 delegation = ["tachys/delegation"]
 islands-router = ["tachys/mark_branches"]
+subsecond = [
+  "reactive_graph/subsecond",
+  "dep:subsecond",
+  "dep:dioxus-cli-config",
+  "dep:dioxus-devtools",
+  "web-sys/Location",
+  "web-sys/MessageEvent",
+  "web-sys/WebSocket",
+  "web-sys/Window",
+]
+lazy = ["tachys/lazy"]
 
 [dev-dependencies]
 tokio = { features = [
@@ -134,13 +155,18 @@ denylist = [
   "trace-component-props",
   "spin",
   "islands",
+  "bitcode",
+  "serde-lite",
+  "cbor",
+  "msgpack",
+  "postcard",
+  "multipart",
 ]
 skip_feature_sets = [
   ["csr", "ssr"],
   ["csr", "hydrate"],
   ["ssr", "hydrate"],
   ["serde", "serde-lite"],
-  ["serde-lite", "miniserde"],
   ["serde", "miniserde"],
   ["serde", "rkyv"],
   ["miniserde", "rkyv"],

leptos/src/children.rs

@@ -262,6 +262,16 @@ where
     }
 }
 
+impl<C> From<View<C>> for ViewFn
+where
+    C: Clone + Send + Sync + 'static,
+    View<C>: IntoAny,
+{
+    fn from(value: View<C>) -> Self {
+        Self(Arc::new(move || value.clone().into_any()))
+    }
+}
+
 impl ViewFn {
     /// Execute the wrapped function
     pub fn run(&self) -> AnyView {
@@ -289,6 +299,16 @@ where
     }
 }
 
+impl<C> From<View<C>> for ViewFnOnce
+where
+    C: Send + Sync + 'static,
+    View<C>: IntoAny,
+{
+    fn from(value: View<C>) -> Self {
+        Self(Box::new(move || value.into_any()))
+    }
+}
+
 impl ViewFnOnce {
     /// Execute the wrapped function
     pub fn run(self) -> AnyView {

leptos/src/hydration/mod.rs

@@ -65,16 +65,56 @@ pub fn HydrationScripts(
     if let Some(splits) = SPLIT_MANIFEST.get_or_init(|| {
         let root = root.clone().unwrap_or_default();
 
+        let (wasm_split_js, wasm_split_manifest) = if options.hash_files {
+            let hash_path = std::env::current_exe()
+                .map(|path| {
+                    path.parent().map(|p| p.to_path_buf()).unwrap_or_default()
+                })
+                .unwrap_or_default()
+                .join(options.hash_file.as_ref());
+            let hashes = std::fs::read_to_string(&hash_path)
+                .expect("failed to read hash file");
+
+            let mut split =
+                "__wasm_split.______________________.js".to_string();
+            let mut manifest = "__wasm_split_manifest.json".to_string();
+            for line in hashes.lines() {
+                let line = line.trim();
+                if !line.is_empty() {
+                    if let Some((file, hash)) = line.split_once(':') {
+                        if file == "manifest" {
+                            manifest.clear();
+                            manifest.push_str("__wasm_split_manifest.");
+                            manifest.push_str(hash.trim());
+                            manifest.push_str(".json");
+                        }
+                        if file == "split" {
+                            split.clear();
+                            split.push_str("__wasm_split.");
+                            split.push_str(hash.trim());
+                            split.push_str(".js");
+                        }
+                    }
+                }
+            }
+            (split, manifest)
+        } else {
+            (
+                "__wasm_split.______________________.js".to_string(),
+                "__wasm_split_manifest.json".to_string(),
+            )
+        };
+
         let site_dir = &options.site_root;
         let pkg_dir = &options.site_pkg_dir;
         let path = PathBuf::from(site_dir.to_string());
-        let path = path
-            .join(pkg_dir.to_string())
-            .join("__wasm_split_manifest.json");
+        let path = path.join(pkg_dir.to_string()).join(wasm_split_manifest);
         let file = std::fs::read_to_string(path).ok()?;
+
         let manifest = WasmSplitManifest(ArcStoredValue::new((
             format!("{root}/{pkg_dir}"),
             serde_json::from_str(&file).expect("could not read manifest file"),
+            wasm_split_js,
         )));
 
         Some(manifest)

leptos/src/hydration/reload_script.js

@@ -1,3 +1,7 @@
+if (window.location.protocol === 'https:') {
+	protocol = 'wss://';
+}
+
 let host = window.location.hostname;
 let ws = new WebSocket(`${protocol}${host}:${reload_port}/live_reload`);
 ws.onmessage = (ev) => {

leptos/src/lib.rs

@@ -1,5 +1,4 @@
 #![deny(missing_docs)]
-#![forbid(unsafe_code)]
 
 //! # About Leptos
 //!
@@ -85,12 +84,22 @@
 //! # Feature Flags
 //!
 //! - **`nightly`**: On `nightly` Rust, enables the function-call syntax for signal getters and setters.
+//!   Also enables some experimental optimizations that improve the handling of static strings and
+//!   the performance of the `template! {}` macro.
 //! - **`csr`** Client-side rendering: Generate DOM nodes in the browser.
 //! - **`ssr`** Server-side rendering: Generate an HTML string (typically on the server).
+//! - **`islands`** Activates “islands mode,” in which components are not made interactive on the
+//!   client unless they use the `#[island]` macro.
 //! - **`hydrate`** Hydration: use this to add interactivity to an SSRed Leptos app.
-//! - **`rkyv`** In SSR/hydrate mode, uses [`rkyv`](https://docs.rs/rkyv/latest/rkyv/) to serialize resources and send them
-//!   from the server to the client.
+//! - **`nonce`** Adds support for nonces to be added as part of a Content Security Policy.
+//! - **`rkyv`** In SSR/hydrate mode, enables using [`rkyv`](https://docs.rs/rkyv/latest/rkyv/) to serialize resources.
 //! - **`tracing`** Adds support for [`tracing`](https://docs.rs/tracing/latest/tracing/).
+//! - **`trace-component-props`** Adds `tracing` support for component props.
+//! - **`delegation`** Uses event delegation rather than the browser’s native event handling
+//!   system. (This improves the performance of creating large numbers of elements simultaneously,
+//!   in exchange for occasional edge cases in which events behave differently from native browser
+//!   events.)
+//! - **`rustls`** Use `rustls` for server functions.
 //!
 //! **Important Note:** You must enable one of `csr`, `hydrate`, or `ssr` to tell Leptos
 //! which mode your app is operating in. You should only enable one of these per build target,
@@ -296,9 +305,15 @@ pub use tachys::mathml as math;
 #[doc(inline)]
 pub use tachys::svg;
 
+#[cfg(feature = "subsecond")]
+/// Utilities for using binary hot-patching with [`subsecond`].
+pub mod subsecond;
+
 /// Utilities for simple isomorphic logging to the console or terminal.
 pub mod logging {
-    pub use leptos_dom::{debug_warn, error, log, warn};
+    pub use leptos_dom::{
+        debug_error, debug_log, debug_warn, error, log, warn,
+    };
 }
 
 /// Utilities for working with asynchronous tasks.
@@ -350,7 +365,8 @@ pub use serde_json;
 pub use tracing;
 #[doc(hidden)]
 pub use wasm_bindgen;
-pub use wasm_split_helpers;
+#[doc(hidden)]
+pub use wasm_split_helpers as wasm_split;
 #[doc(hidden)]
 pub use web_sys;
 
@@ -382,7 +398,8 @@ pub fn prefetch_lazy_fn_on_server(id: &'static str) {
 #[derive(Clone, Debug, Default)]
 pub struct WasmSplitManifest(
     pub  reactive_graph::owner::ArcStoredValue<(
-        String,
-        std::collections::HashMap<String, Vec<String>>,
+        String,                                         // the pkg root
+        std::collections::HashMap<String, Vec<String>>, // preloads
+        String, // the name of the __wasm_split.js file
     )>,
 );

leptos/src/subsecond.rs

@@ -0,0 +1,62 @@
+use dioxus_devtools::DevserverMsg;
+use wasm_bindgen::{prelude::Closure, JsCast};
+use web_sys::{js_sys::JsString, MessageEvent, WebSocket};
+
+/// Sets up a websocket connect to the `dx` CLI, waiting for incoming hot-patching messages
+/// and patching the WASM binary appropriately.
+//
+//  Note: This is a stripped-down version of Dioxus's `make_ws` from `dioxus_web`
+//  It's essentially copy-pasted here because it's not pub there.
+//  Would love to just take a dependency on that to be able to use it and deduplicate.
+//
+//  https://github.com/DioxusLabs/dioxus/blob/main/packages/web/src/devtools.rs#L36
+pub fn connect_to_hot_patch_messages() {
+    // Get the location of the devserver, using the current location plus the /_dioxus path
+    // The idea here being that the devserver is always located on the /_dioxus behind a proxy
+    let location = web_sys::window().unwrap().location();
+    let url = format!(
+        "{protocol}//{host}/_dioxus?build_id={build_id}",
+        protocol = match location.protocol().unwrap() {
+            prot if prot == "https:" => "wss:",
+            _ => "ws:",
+        },
+        host = location.host().unwrap(),
+        build_id = dioxus_cli_config::build_id(),
+    );
+
+    let ws = WebSocket::new(&url).unwrap();
+
+    ws.set_onmessage(Some(
+        Closure::<dyn FnMut(MessageEvent)>::new(move |e: MessageEvent| {
+            let Ok(text) = e.data().dyn_into::<JsString>() else {
+                return;
+            };
+
+            // The devserver messages have some &'static strs in them, so we need to leak the source string
+            let string: String = text.into();
+            let string = Box::leak(string.into_boxed_str());
+
+            if let Ok(DevserverMsg::HotReload(msg)) =
+                serde_json::from_str::<DevserverMsg>(string)
+            {
+                if let Some(jump_table) = msg.jump_table.as_ref().cloned() {
+                    if msg.for_build_id == Some(dioxus_cli_config::build_id()) {
+                        let our_pid = if cfg!(target_family = "wasm") {
+                            None
+                        } else {
+                            Some(std::process::id())
+                        };
+
+                        if msg.for_pid == our_pid {
+                            unsafe { subsecond::apply_patch(jump_table) }
+                                .unwrap();
+                        }
+                    }
+                }
+            }
+        })
+        .into_js_value()
+        .as_ref()
+        .unchecked_ref(),
+    ));
+}

leptos/src/suspense_component.rs

@@ -32,12 +32,12 @@ use tachys::{
 };
 use throw_error::ErrorHookFuture;
 
-/// If any [`Resource`](leptos_reactive::Resource) is read in the `children` of this
+/// If any [`Resource`](crate::prelude::Resource) is read in the `children` of this
 /// component, it will show the `fallback` while they are loading. Once all are resolved,
 /// it will render the `children`.
 ///
 /// Each time one of the resources is loading again, it will fall back. To keep the current
-/// children instead, use [Transition](crate::Transition).
+/// children instead, use [Transition](crate::prelude::Transition).
 ///
 /// Note that the `children` will be rendered initially (in order to capture the fact that
 /// those resources are read under the suspense), so you cannot assume that resources read

leptos/src/transition.rs

@@ -16,11 +16,11 @@ use reactive_graph::{
 use slotmap::{DefaultKey, SlotMap};
 use tachys::reactive_graph::OwnedView;
 
-/// If any [`Resource`](leptos_reactive::Resource) is read in the `children` of this
+/// If any [`Resource`](crate::prelude::Resource) is read in the `children` of this
 /// component, it will show the `fallback` while they are loading. Once all are resolved,
 /// it will render the `children`.
 ///
-/// Unlike [`Suspense`](crate::Suspense), this will not fall
+/// Unlike [`Suspense`](crate::prelude::Suspense), this will not fall
 /// back to the `fallback` state if there are further changes after the initial load.
 ///
 /// Note that the `children` will be rendered initially (in order to capture the fact that

leptos_config/src/lib.rs

@@ -221,18 +221,15 @@ fn env_w_default(
 /// An enum that can be used to define the environment Leptos is running in.
 /// Setting this to the `PROD` variant will not include the WebSocket code for `cargo-leptos` watch mode.
 /// Defaults to `DEV`.
-#[derive(Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq, Eq)]
+#[derive(
+    Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq, Eq, Default,
+)]
 pub enum Env {
     PROD,
+    #[default]
     DEV,
 }
 
-impl Default for Env {
-    fn default() -> Self {
-        Self::DEV
-    }
-}
-
 fn env_from_str(input: &str) -> Result<Env, LeptosConfigError> {
     let sanitized = input.to_lowercase();
     match sanitized.as_ref() {
@@ -279,18 +276,15 @@ impl TryFrom<String> for Env {
 
 /// An enum that can be used to define the websocket protocol Leptos uses for hotreloading
 /// Defaults to `ws`.
-#[derive(Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq, Eq)]
+#[derive(
+    Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq, Eq, Default,
+)]
 pub enum ReloadWSProtocol {
+    #[default]
     WS,
     WSS,
 }
 
-impl Default for ReloadWSProtocol {
-    fn default() -> Self {
-        Self::WS
-    }
-}
-
 fn ws_from_str(input: &str) -> Result<ReloadWSProtocol, LeptosConfigError> {
     let sanitized = input.to_lowercase();
     match sanitized.as_ref() {

leptos_dom/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "leptos_dom"
-version = "0.8.6"
+version = "0.8.7"
 authors = ["Greg Johnston"]
 license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"

leptos_dom/src/helpers.rs

@@ -463,7 +463,7 @@ pub fn set_interval_with_handle(
 
     #[inline(never)]
     fn si(
-        cb: Box<dyn Fn()>,
+        cb: Box<dyn FnMut()>,
         duration: Duration,
     ) -> Result<IntervalHandle, JsValue> {
         let cb = Closure::wrap(cb).into_js_value();

leptos_macro/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "leptos_macro"
-version = "0.8.8"
+version = "0.8.11"
 authors = ["Greg Johnston"]
 license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"

leptos_macro/src/lazy.rs

@@ -2,12 +2,12 @@ use convert_case::{Case, Casing};
 use proc_macro::TokenStream;
 use proc_macro2::Ident;
 use proc_macro_error2::abort;
-use quote::quote;
+use quote::{format_ident, quote};
 use std::{
     hash::{DefaultHasher, Hash, Hasher},
     mem,
 };
-use syn::{parse_macro_input, ItemFn};
+use syn::{parse_macro_input, parse_quote, ItemFn, ReturnType, Stmt};
 
 pub fn lazy_impl(args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
     let name = if !args.is_empty() {
@@ -16,7 +16,7 @@ pub fn lazy_impl(args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
         None
     };
 
-    let mut fun = syn::parse::<ItemFn>(s).unwrap_or_else(|e| {
+    let fun = syn::parse::<ItemFn>(s).unwrap_or_else(|e| {
         abort!(e.span(), "`lazy` can only be used on a function")
     });
 
@@ -47,29 +47,50 @@ pub fn lazy_impl(args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
 
     let is_wasm = cfg!(feature = "csr") || cfg!(feature = "hydrate");
     if is_wasm {
+        let mut fun = fun;
+        let mut return_wrapper = None;
+        if was_async {
+            fun.sig.asyncness = None;
+            let ty = match &fun.sig.output {
+                ReturnType::Default => quote! { () },
+                ReturnType::Type(_, ty) => quote! { #ty },
+            };
+            let sync_output: ReturnType = parse_quote! {
+                -> ::std::pin::Pin<::std::boxed::Box<dyn ::std::future::Future<Output = #ty> + ::std::marker::Send + ::std::marker::Sync>>
+            };
+            let async_output = mem::replace(&mut fun.sig.output, sync_output);
+            let stmts = mem::take(&mut fun.block.stmts);
+            fun.block.stmts.push(Stmt::Expr(parse_quote! {
+                ::std::boxed::Box::pin(::leptos::__reexports::send_wrapper::SendWrapper::new(async move {
+                    #( #stmts )*
+                }))
+            }, None));
+            return_wrapper = Some(quote! {
+                return_wrapper(let future = _; { future.await } #async_output),
+            });
+        }
+        let preload_name = format_ident!("__preload_{}", fun.sig.ident);
+
         quote! {
-            #[::leptos::wasm_split_helpers::wasm_split(
+            #[::leptos::wasm_split::wasm_split(
                 #unique_name,
-                ::leptos::__reexports::send_wrapper
+                wasm_split_path = ::leptos::wasm_split,
+                preload(#[doc(hidden)] #[allow(non_snake_case)] #preload_name),
+                #return_wrapper
             )]
             #fun
         }
     } else {
+        let mut fun = fun;
         if !was_async {
             fun.sig.asyncness = Some(Default::default());
         }
 
         let statements = &mut fun.block.stmts;
         let old_statements = mem::take(statements);
-        statements.push(
-            syn::parse(
-                quote! {
-                    ::leptos::prefetch_lazy_fn_on_server(#unique_name_str);
-                }
-                .into(),
-            )
-            .unwrap(),
-        );
+        statements.push(parse_quote! {
+            ::leptos::prefetch_lazy_fn_on_server(#unique_name_str);
+        });
         statements.extend(old_statements);
         quote! { #fun }
     }

leptos_macro/src/view/mod.rs

@@ -25,9 +25,8 @@ use std::{
 use syn::{
     punctuated::Pair::{End, Punctuated},
     spanned::Spanned,
-    Expr,
-    Expr::Tuple,
-    ExprArray, ExprLit, ExprRange, Lit, LitStr, RangeLimits, Stmt,
+    Expr::{self, Tuple},
+    ExprArray, ExprLit, ExprPath, ExprRange, Lit, LitStr, RangeLimits, Stmt,
 };
 
 #[derive(Clone, Copy, PartialEq, Eq)]
@@ -1679,7 +1678,7 @@ fn attribute_value(
 }
 
 // Keep list alphabetized for binary search
-const TYPED_EVENTS: [&str; 126] = [
+const TYPED_EVENTS: [&str; 127] = [
     "DOMContentLoaded",
     "abort",
     "afterprint",
@@ -1775,6 +1774,7 @@ const TYPED_EVENTS: [&str; 126] = [
     "reset",
     "resize",
     "scroll",
+    "scrollend",
     "securitypolicyviolation",
     "seeked",
     "seeking",
@@ -1871,6 +1871,28 @@ pub(crate) fn ident_from_tag_name(tag_name: &NodeName) -> Ident {
     }
 }
 
+pub(crate) fn full_path_from_tag_name(tag_name: &NodeName) -> Option<ExprPath> {
+    match tag_name {
+        NodeName::Path(path) => Some(path.clone()),
+        NodeName::Block(_) => {
+            let span = tag_name.span();
+            proc_macro_error2::emit_error!(
+                span,
+                "blocks not allowed in tag-name position"
+            );
+            None
+        }
+        _ => {
+            let span = tag_name.span();
+            proc_macro_error2::emit_error!(
+                span,
+                "punctuated names not allowed in slots"
+            );
+            None
+        }
+    }
+}
+
 pub(crate) fn directive_call_from_attribute_node(
     attr: &KeyedAttribute,
     directive_name: &str,

leptos_macro/src/view/slot_helper.rs

@@ -1,6 +1,6 @@
 use super::{
     component_builder::maybe_optimised_component_children,
-    convert_to_snake_case, ident_from_tag_name,
+    convert_to_snake_case, full_path_from_tag_name,
 };
 use crate::view::{fragment_to_tokens, utils::filter_prefixed_attrs, TagType};
 use proc_macro2::{Ident, TokenStream, TokenTree};
@@ -24,7 +24,7 @@ pub(crate) fn slot_to_tokens(
         node.name().to_string()
     });
 
-    let component_name = ident_from_tag_name(node.name());
+    let component_path = full_path_from_tag_name(node.name());
 
     let Some(parent_slots) = parent_slots else {
         proc_macro_error2::emit_error!(
@@ -190,7 +190,7 @@ pub(crate) fn slot_to_tokens(
 
     let slot = quote_spanned! {node.span()=>
         {
-            let slot = #component_name::builder()
+            let slot = #component_path::builder()
                 #(#props)*
                 #(#slots)*
                 #children

projects/hexagonal-architecture/end2end/package-lock.json

@@ -15,19 +15,18 @@
       }
     },
     "node_modules/@playwright/test": {
-      "version": "1.44.1",
-      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.44.1.tgz",
-      "integrity": "sha512-1hZ4TNvD5z9VuhNJ/walIjvMVvYkZKf71axoF/uiAqpntQJXpG64dlXhoDXE3OczPuTuvjf/M5KWFg5VAVUS3Q==",
+      "version": "1.56.1",
+      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.56.1.tgz",
+      "integrity": "sha512-vSMYtL/zOcFpvJCW71Q/OEGQb7KYBPAdKh35WNSkaZA75JlAO8ED8UN6GUNTm3drWomcbcqRPFqQbLae8yBTdg==",
       "dev": true,
-      "license": "Apache-2.0",
       "dependencies": {
-        "playwright": "1.44.1"
+        "playwright": "1.56.1"
       },
       "bin": {
         "playwright": "cli.js"
       },
       "engines": {
-        "node": ">=16"
+        "node": ">=18"
       }
     },
     "node_modules/@types/node": {
@@ -46,7 +45,6 @@
       "integrity": "sha512-xiqMQR4xAeHTuB9uWm+fFRcIOgKBMiOBP+eXiyT7jsgVCq1bkVygt00oASowB7EdtpOHaaPgKt812P9ab+DDKA==",
       "dev": true,
       "hasInstallScript": true,
-      "license": "MIT",
       "optional": true,
       "os": [
         "darwin"
@@ -56,35 +54,33 @@
       }
     },
     "node_modules/playwright": {
-      "version": "1.44.1",
-      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.44.1.tgz",
-      "integrity": "sha512-qr/0UJ5CFAtloI3avF95Y0L1xQo6r3LQArLIg/z/PoGJ6xa+EwzrwO5lpNr/09STxdHuUoP2mvuELJS+hLdtgg==",
+      "version": "1.56.1",
+      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.56.1.tgz",
+      "integrity": "sha512-aFi5B0WovBHTEvpM3DzXTUaeN6eN0qWnTkKx4NQaH4Wvcmc153PdaY2UBdSYKaGYw+UyWXSVyxDUg5DoPEttjw==",
       "dev": true,
-      "license": "Apache-2.0",
       "dependencies": {
-        "playwright-core": "1.44.1"
+        "playwright-core": "1.56.1"
       },
       "bin": {
         "playwright": "cli.js"
       },
       "engines": {
-        "node": ">=16"
+        "node": ">=18"
       },
       "optionalDependencies": {
         "fsevents": "2.3.2"
       }
     },
     "node_modules/playwright-core": {
-      "version": "1.44.1",
-      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.44.1.tgz",
-      "integrity": "sha512-wh0JWtYTrhv1+OSsLPgFzGzt67Y7BE/ZS3jEqgGBlp2ppp1ZDj8c+9IARNW4dwf1poq5MgHreEM2KV/GuR4cFA==",
+      "version": "1.56.1",
+      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.56.1.tgz",
+      "integrity": "sha512-hutraynyn31F+Bifme+Ps9Vq59hKuUCz7H1kDOcBs+2oGguKkWTU50bBWrtz34OUWmIwpBTWDxaRPXrIXkgvmQ==",
       "dev": true,
-      "license": "Apache-2.0",
       "bin": {
         "playwright-core": "cli.js"
       },
       "engines": {
-        "node": ">=16"
+        "node": ">=18"
       }
     },
     "node_modules/typescript": {
@@ -111,12 +107,12 @@
   },
   "dependencies": {
     "@playwright/test": {
-      "version": "1.44.1",
-      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.44.1.tgz",
-      "integrity": "sha512-1hZ4TNvD5z9VuhNJ/walIjvMVvYkZKf71axoF/uiAqpntQJXpG64dlXhoDXE3OczPuTuvjf/M5KWFg5VAVUS3Q==",
+      "version": "1.56.1",
+      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.56.1.tgz",
+      "integrity": "sha512-vSMYtL/zOcFpvJCW71Q/OEGQb7KYBPAdKh35WNSkaZA75JlAO8ED8UN6GUNTm3drWomcbcqRPFqQbLae8yBTdg==",
       "dev": true,
       "requires": {
-        "playwright": "1.44.1"
+        "playwright": "1.56.1"
       }
     },
     "@types/node": {
@@ -136,19 +132,19 @@
       "optional": true
     },
     "playwright": {
-      "version": "1.44.1",
-      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.44.1.tgz",
-      "integrity": "sha512-qr/0UJ5CFAtloI3avF95Y0L1xQo6r3LQArLIg/z/PoGJ6xa+EwzrwO5lpNr/09STxdHuUoP2mvuELJS+hLdtgg==",
+      "version": "1.56.1",
+      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.56.1.tgz",
+      "integrity": "sha512-aFi5B0WovBHTEvpM3DzXTUaeN6eN0qWnTkKx4NQaH4Wvcmc153PdaY2UBdSYKaGYw+UyWXSVyxDUg5DoPEttjw==",
       "dev": true,
       "requires": {
         "fsevents": "2.3.2",
-        "playwright-core": "1.44.1"
+        "playwright-core": "1.56.1"
       }
     },
     "playwright-core": {
-      "version": "1.44.1",
-      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.44.1.tgz",
-      "integrity": "sha512-wh0JWtYTrhv1+OSsLPgFzGzt67Y7BE/ZS3jEqgGBlp2ppp1ZDj8c+9IARNW4dwf1poq5MgHreEM2KV/GuR4cFA==",
+      "version": "1.56.1",
+      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.56.1.tgz",
+      "integrity": "sha512-hutraynyn31F+Bifme+Ps9Vq59hKuUCz7H1kDOcBs+2oGguKkWTU50bBWrtz34OUWmIwpBTWDxaRPXrIXkgvmQ==",
       "dev": true
     },
     "typescript": {

reactive_graph/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "reactive_graph"
-version = "0.2.6"
+version = "0.2.9"
 authors = ["Greg Johnston"]
 license = "MIT"
 readme = "../README.md"
@@ -27,6 +27,7 @@ async-lock = { workspace = true, default-features = true }
 send_wrapper = { features = [
   "futures",
 ], workspace = true, default-features = true }
+subsecond = { workspace = true, default-features = true, optional = true }
 indexmap = { workspace = true, default-features = true }
 
 [target.'cfg(all(target_arch = "wasm32", target_os = "unknown"))'.dependencies]
@@ -51,6 +52,7 @@ hydration = ["dep:hydration_context"]
 effects = [
 ] # whether to run effects: should be disabled for something like server rendering
 sandboxed-arenas = []
+subsecond = ["dep:subsecond"]
 
 [package.metadata.docs.rs]
 all-features = true

reactive_graph/src/actions/action.rs

@@ -1,7 +1,8 @@
 use crate::{
-    computed::{ArcMemo, Memo},
+    computed::{ArcMemo, Memo, ScopedFuture},
     diagnostics::is_suppressing_resource_load,
-    owner::{ArcStoredValue, ArenaItem},
+    graph::untrack,
+    owner::{ArcStoredValue, ArenaItem, Owner},
     send_wrapper_ext::SendOption,
     signal::{ArcMappedSignal, ArcRwSignal, MappedSignal, RwSignal},
     traits::{DefinedAt, Dispose, Get, GetUntracked, GetValue, Update, Write},
@@ -199,13 +200,18 @@ where
         I: Send + Sync,
         O: Send + Sync,
     {
+        let owner = Owner::current().unwrap_or_default();
         ArcAction {
             in_flight: ArcRwSignal::new(0),
             input: ArcRwSignal::new(SendOption::new(None)),
             value: ArcRwSignal::new(SendOption::new(value)),
             version: Default::default(),
             dispatched: Default::default(),
-            action_fn: Arc::new(move |input| Box::pin(action_fn(input))),
+            action_fn: Arc::new(move |input| {
+                Box::pin(owner.with(|| {
+                    ScopedFuture::new_untracked(untrack(|| action_fn(input)))
+                }))
+            }),
             #[cfg(any(debug_assertions, leptos_debuginfo))]
             defined_at: Location::caller(),
         }
@@ -370,6 +376,7 @@ where
         F: Fn(&I) -> Fu + 'static,
         Fu: Future<Output = O> + 'static,
     {
+        let owner = Owner::current().unwrap_or_default();
         let action_fn = SendWrapper::new(action_fn);
         ArcAction {
             in_flight: ArcRwSignal::new(0),
@@ -378,7 +385,9 @@ where
             version: Default::default(),
             dispatched: Default::default(),
             action_fn: Arc::new(move |input| {
-                Box::pin(SendWrapper::new(action_fn(input)))
+                Box::pin(SendWrapper::new(owner.with(|| {
+                    ScopedFuture::new_untracked(untrack(|| action_fn(input)))
+                })))
             }),
             #[cfg(any(debug_assertions, leptos_debuginfo))]
             defined_at: Location::caller(),

reactive_graph/src/computed/async_derived/arc_async_derived.rs

@@ -521,9 +521,10 @@ impl<T: 'static> ArcAsyncDerived<T> {
     {
         let fun = move || {
             let fut = fun();
-            let fut = ScopedFuture::new_untracked(async move {
-                SendOption::new(Some(fut.await))
-            });
+            let fut =
+                ScopedFuture::new_untracked_with_diagnostics(async move {
+                    SendOption::new(Some(fut.await))
+                });
             #[cfg(feature = "sandboxed-arenas")]
             let fut = Sandboxed::new(fut);
             fut

reactive_graph/src/computed/async_derived/mod.rs

@@ -54,11 +54,55 @@ impl<Fut> ScopedFuture<Fut> {
             fut,
         }
     }
+
+    #[doc(hidden)]
+    #[track_caller]
+    pub fn new_untracked_with_diagnostics(
+        fut: Fut,
+    ) -> ScopedFutureUntrackedWithDiagnostics<Fut> {
+        let owner = Owner::current().unwrap_or_default();
+        ScopedFutureUntrackedWithDiagnostics {
+            owner,
+            observer: None,
+            fut,
+        }
+    }
 }
 
 impl<Fut: Future> Future for ScopedFuture<Fut> {
     type Output = Fut::Output;
 
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let this = self.project();
+        this.owner.with(|| {
+            #[cfg(debug_assertions)]
+            let _maybe_guard = if this.observer.is_none() {
+                Some(crate::diagnostics::SpecialNonReactiveZone::enter())
+            } else {
+                None
+            };
+            this.observer.with_observer(|| this.fut.poll(cx))
+        })
+    }
+}
+
+pin_project! {
+    /// A [`Future`] wrapper that sets the [`Owner`] and [`Observer`] before polling the inner
+    /// `Future`, output of [`ScopedFuture::new_untracked_with_diagnostics`].
+    ///
+    /// In leptos 0.9 this will be replaced with `ScopedFuture` itself.
+    #[derive(Clone)]
+    pub struct ScopedFutureUntrackedWithDiagnostics<Fut> {
+        owner: Owner,
+        observer: Option<AnySubscriber>,
+        #[pin]
+        fut: Fut,
+    }
+}
+
+impl<Fut: Future> Future for ScopedFutureUntrackedWithDiagnostics<Fut> {
+    type Output = Fut::Output;
+
     fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         let this = self.project();
         this.owner

reactive_graph/src/effect/immediate.rs

@@ -65,6 +65,7 @@ impl Dispose for ImmediateEffect {
 
 impl ImmediateEffect {
     /// Creates a new effect which runs immediately, then again as soon as any tracked signal changes.
+    /// (Unless [batch] is used.)
     ///
     /// NOTE: this requires a `Fn` function because it might recurse.
     /// Use [Self::new_mut] to pass a `FnMut` function, it'll panic on recursion.
@@ -82,6 +83,7 @@ impl ImmediateEffect {
         Self { inner: Some(inner) }
     }
     /// Creates a new effect which runs immediately, then again as soon as any tracked signal changes.
+    /// (Unless [batch] is used.)
     ///
     /// # Panics
     /// Panics on recursion or if triggered in parallel. Also see [Self::new]
@@ -93,8 +95,10 @@ impl ImmediateEffect {
         Self::new(move || fun.try_lock().expect(MSG)())
     }
     /// Creates a new effect which runs immediately, then again as soon as any tracked signal changes.
+    /// (Unless [batch] is used.)
     ///
     /// NOTE: this requires a `Fn` function because it might recurse.
+    /// Use [Self::new_mut_scoped] to pass a `FnMut` function, it'll panic on recursion.
     /// NOTE: this effect is automatically cleaned up when the current owner is cleared or disposed.
     #[track_caller]
     pub fn new_scoped(fun: impl Fn() + Send + Sync + 'static) {
@@ -102,6 +106,19 @@ impl ImmediateEffect {
 
         on_cleanup(move || effect.dispose());
     }
+    /// Creates a new effect which runs immediately, then again as soon as any tracked signal changes.
+    /// (Unless [batch] is used.)
+    ///
+    /// NOTE: this effect is automatically cleaned up when the current owner is cleared or disposed.
+    ///
+    /// # Panics
+    /// Panics on recursion or if triggered in parallel. Also see [Self::new_scoped]
+    #[track_caller]
+    pub fn new_mut_scoped(fun: impl FnMut() + Send + Sync + 'static) {
+        let effect = Self::new_mut(fun);
+
+        on_cleanup(move || effect.dispose());
+    }
 
     /// Creates a new effect which runs immediately, then again as soon as any tracked signal changes.
     ///
@@ -130,6 +147,41 @@ impl DefinedAt for ImmediateEffect {
     }
 }
 
+/// Defers any [ImmediateEffect]s from running until the end of the function.
+///
+/// NOTE: this affects only [ImmediateEffect]s, not other effects.
+///
+/// NOTE: this is rarely needed, but it is useful for example when multiple signals
+/// need to be updated atomically (for example a double-bound signal tree).
+pub fn batch<T>(f: impl FnOnce() -> T) -> T {
+    struct ExecuteOnDrop;
+    impl Drop for ExecuteOnDrop {
+        fn drop(&mut self) {
+            let effects = {
+                let mut batch = inner::BATCH.write().or_poisoned();
+                batch.take().unwrap().into_inner().expect("lock poisoned")
+            };
+            // TODO: Should we skip the effects if it's panicking?
+            for effect in effects {
+                effect.update_if_necessary();
+            }
+        }
+    }
+    let mut execute_on_drop = None;
+    {
+        let mut batch = inner::BATCH.write().or_poisoned();
+        if batch.is_none() {
+            execute_on_drop = Some(ExecuteOnDrop);
+        } else {
+            // Nested batching has no effect.
+        }
+        *batch = Some(batch.take().unwrap_or_default());
+    }
+    let ret = f();
+    drop(execute_on_drop);
+    ret
+}
+
 mod inner {
     use crate::{
         graph::{
@@ -140,6 +192,7 @@ mod inner {
         owner::Owner,
         traits::DefinedAt,
     };
+    use indexmap::IndexSet;
     use or_poisoned::OrPoisoned;
     use std::{
         panic::Location,
@@ -147,6 +200,11 @@ mod inner {
         thread::{self, ThreadId},
     };
 
+    /// Only the [super::batch] function ever writes to the outer RwLock.
+    /// While the effects will write to the inner one.
+    pub(super) static BATCH: RwLock<Option<RwLock<IndexSet<AnySubscriber>>>> =
+        RwLock::new(None);
+
     /// Handles subscription logic for effects.
     ///
     /// To handle parallelism and recursion we assign ordered (1..) ids to each run.
@@ -202,6 +260,8 @@ mod inner {
             fun: impl Fn() + Send + Sync + 'static,
         ) -> Arc<RwLock<EffectInner>> {
             let owner = Owner::new();
+            #[cfg(any(debug_assertions, leptos_debuginfo))]
+            let defined_at = Location::caller();
 
             Arc::new_cyclic(|weak| {
                 let any_subscriber = AnySubscriber(
@@ -211,7 +271,7 @@ mod inner {
 
                 RwLock::new(EffectInner {
                     #[cfg(any(debug_assertions, leptos_debuginfo))]
-                    defined_at: Location::caller(),
+                    defined_at,
                     owner,
                     state: ReactiveNodeState::Dirty,
                     run_count_start: 0,
@@ -260,6 +320,17 @@ mod inner {
                 ReactiveNodeState::Dirty => true,
             };
 
+            {
+                if let Some(batch) = &*BATCH.read().or_poisoned() {
+                    let mut batch = batch.write().or_poisoned();
+                    let subscriber =
+                        self.read().or_poisoned().any_subscriber.clone();
+
+                    batch.insert(subscriber);
+                    return needs_update;
+                }
+            }
+
             if needs_update {
                 let mut guard = self.write().or_poisoned();
 

reactive_graph/src/effect/render_effect.rs

@@ -9,6 +9,8 @@ use crate::{
 };
 use futures::StreamExt;
 use or_poisoned::OrPoisoned;
+#[cfg(feature = "subsecond")]
+use std::sync::Mutex;
 use std::{
     fmt::Debug,
     future::{Future, IntoFuture},
@@ -49,13 +51,39 @@ impl<T> Debug for RenderEffect<T> {
     }
 }
 
+#[cfg(feature = "subsecond")]
+type CurrentHotPtr = Box<dyn Fn() -> Option<subsecond::HotFnPtr> + Send + Sync>;
+
 impl<T> RenderEffect<T>
 where
     T: 'static,
 {
     /// Creates a new render effect, which immediately runs `fun`.
     pub fn new(fun: impl FnMut(Option<T>) -> T + 'static) -> Self {
-        Self::new_with_value_erased(Box::new(fun), None)
+        #[cfg(feature = "subsecond")]
+        let (hot_fn_ptr, fun) = {
+            let fun = Arc::new(Mutex::new(subsecond::HotFn::current(fun)));
+            (
+                {
+                    let fun = Arc::downgrade(&fun);
+                    let wrapped = send_wrapper::SendWrapper::new(move || {
+                        fun.upgrade()
+                            .map(|n| n.lock().or_poisoned().ptr_address())
+                    });
+                    // it's not redundant, it's due to the SendWrapper deref
+                    #[allow(clippy::redundant_closure)]
+                    Box::new(move || wrapped())
+                },
+                move |prev| fun.lock().or_poisoned().call((prev,)),
+            )
+        };
+
+        Self::new_with_value_erased(
+            Box::new(fun),
+            None,
+            #[cfg(feature = "subsecond")]
+            hot_fn_ptr,
+        )
     }
 
     /// Creates a new render effect with an initial value.
@@ -63,7 +91,30 @@ where
         fun: impl FnMut(Option<T>) -> T + 'static,
         initial_value: Option<T>,
     ) -> Self {
-        Self::new_with_value_erased(Box::new(fun), initial_value)
+        #[cfg(feature = "subsecond")]
+        let (hot_fn_ptr, fun) = {
+            let fun = Arc::new(Mutex::new(subsecond::HotFn::current(fun)));
+            (
+                {
+                    let fun = Arc::downgrade(&fun);
+                    let wrapped = send_wrapper::SendWrapper::new(move || {
+                        fun.upgrade()
+                            .map(|n| n.lock().or_poisoned().ptr_address())
+                    });
+                    // it's not redundant, it's due to the SendWrapper deref
+                    #[allow(clippy::redundant_closure)]
+                    Box::new(move || wrapped())
+                },
+                move |prev| fun.lock().or_poisoned().call((prev,)),
+            )
+        };
+
+        Self::new_with_value_erased(
+            Box::new(fun),
+            initial_value,
+            #[cfg(feature = "subsecond")]
+            hot_fn_ptr,
+        )
     }
 
     /// Creates a new render effect, which immediately runs `fun`.
@@ -71,6 +122,11 @@ where
         fun: impl FnMut(Option<T>) -> T + 'static,
         value: impl IntoFuture<Output = T> + 'static,
     ) -> Self {
+        #[cfg(feature = "subsecond")]
+        let mut fun = subsecond::HotFn::current(fun);
+        #[cfg(feature = "subsecond")]
+        let fun = move |prev| fun.call((prev,));
+
         Self::new_with_async_value_erased(
             Box::new(fun),
             Box::pin(value.into_future()),
@@ -79,8 +135,13 @@ where
     }
 
     fn new_with_value_erased(
-        mut fun: Box<dyn FnMut(Option<T>) -> T + 'static>,
+        #[allow(unused_mut)] mut fun: Box<dyn FnMut(Option<T>) -> T + 'static>,
         initial_value: Option<T>,
+        // this argument can be used to invalidate individual effects in the future
+        // in present experiments, I have found that it is not actually granular enough to make a difference
+        #[allow(unused)]
+        #[cfg(feature = "subsecond")]
+        hot_fn_ptr: CurrentHotPtr,
     ) -> Self {
         // codegen optimisation:
         fn prep() -> (Owner, Arc<RwLock<EffectInner>>, crate::channel::Receiver)
@@ -104,12 +165,56 @@ where
             let _ = initial_value;
             let _ = owner;
             let _ = &mut rx;
-            let _ = &mut fun;
+            let _ = fun;
         }
 
         #[cfg(feature = "effects")]
         {
             let subscriber = inner.to_any_subscriber();
+
+            #[cfg(all(feature = "subsecond", debug_assertions))]
+            let mut fun = {
+                use crate::graph::ReactiveNode;
+                use rustc_hash::FxHashMap;
+                use std::sync::{Arc, LazyLock, Mutex};
+                use subsecond::HotFnPtr;
+
+                static HOT_RELOAD_SUBSCRIBERS: LazyLock<
+                    Mutex<FxHashMap<AnySubscriber, (HotFnPtr, CurrentHotPtr)>>,
+                > = LazyLock::new(|| {
+                    subsecond::register_handler(Arc::new(|| {
+                        HOT_RELOAD_SUBSCRIBERS.lock().or_poisoned().retain(
+                            |subscriber, (prev_ptr, hot_fn_ptr)| {
+                                match hot_fn_ptr() {
+                                    None => false,
+                                    Some(curr_hot_ptr) => {
+                                        if curr_hot_ptr != *prev_ptr {
+                                            crate::log_warning(format_args!(
+                                                "{prev_ptr:?} <> \
+                                                 {curr_hot_ptr:?}",
+                                            ));
+                                            *prev_ptr = curr_hot_ptr;
+
+                                            subscriber.mark_dirty();
+                                        }
+                                        true
+                                    }
+                                }
+                            },
+                        );
+                    }));
+                    Default::default()
+                });
+
+                let mut fun = subsecond::HotFn::current(fun);
+                let initial_ptr = hot_fn_ptr().unwrap();
+                HOT_RELOAD_SUBSCRIBERS
+                    .lock()
+                    .or_poisoned()
+                    .insert(subscriber.clone(), (initial_ptr, hot_fn_ptr));
+                move |prev| fun.call((prev,))
+            };
+
             *value.write().or_poisoned() = Some(
                 owner.with(|| subscriber.with_observer(|| fun(initial_value))),
             );
@@ -230,6 +335,11 @@ where
     pub fn new_isomorphic(
         fun: impl FnMut(Option<T>) -> T + Send + Sync + 'static,
     ) -> Self {
+        #[cfg(feature = "subsecond")]
+        let mut fun = subsecond::HotFn::current(fun);
+        #[cfg(feature = "subsecond")]
+        let fun = move |prev| fun.call((prev,));
+
         fn erased<T: Send + Sync + 'static>(
             mut fun: Box<dyn FnMut(Option<T>) -> T + Send + Sync + 'static>,
         ) -> RenderEffect<T> {

reactive_graph/src/owner.rs

@@ -209,6 +209,25 @@ impl Owner {
         this
     }
 
+    /// Returns the parent of this `Owner`, if any.
+    ///
+    /// None when:
+    /// - This is a root owner
+    /// - The parent has been dropped
+    pub fn parent(&self) -> Option<Owner> {
+        self.inner
+            .read()
+            .or_poisoned()
+            .parent
+            .as_ref()
+            .and_then(|p| p.upgrade())
+            .map(|inner| Owner {
+                inner,
+                #[cfg(feature = "hydration")]
+                shared_context: self.shared_context.clone(),
+            })
+    }
+
     /// Creates a new `Owner` that is the child of the current `Owner`, if any.
     pub fn child(&self) -> Self {
         let parent = Some(Arc::downgrade(&self.inner));
@@ -321,6 +340,8 @@ impl Owner {
     }
 
     /// Removes this from its state as the thread-local owner and drops it.
+    /// If there are other holders of this owner, it may not cleanup, if always cleaning up is required,
+    /// see [`Owner::unset_with_forced_cleanup`].
     pub fn unset(self) {
         OWNER.with_borrow_mut(|owner| {
             if owner.as_ref().and_then(|n| n.upgrade()) == Some(self) {
@@ -329,6 +350,23 @@ impl Owner {
         })
     }
 
+    /// Removes this from its state as the thread-local owner and drops it.
+    /// Unlike [`Owner::unset`], this will always run cleanup on this owner,
+    /// even if there are other holders of this owner.
+    pub fn unset_with_forced_cleanup(self) {
+        OWNER.with_borrow_mut(|owner| {
+            if owner
+                .as_ref()
+                .and_then(|n| n.upgrade())
+                .map(|o| o == self)
+                .unwrap_or(false)
+            {
+                mem::take(owner);
+            }
+        });
+        self.cleanup();
+    }
+
     /// Returns the current [`SharedContext`], if any.
     #[cfg(feature = "hydration")]
     pub fn current_shared_context(

reactive_graph/src/wrappers.rs

@@ -257,6 +257,20 @@ pub mod read {
         }
     }
 
+    impl<T, S> From<ReadSignal<T, S>> for ArcSignal<T, S>
+    where
+        S: Storage<ArcReadSignal<T>> + Storage<T>,
+    {
+        #[track_caller]
+        fn from(value: ReadSignal<T, S>) -> Self {
+            Self {
+                inner: SignalTypes::ReadSignal(value.into()),
+                #[cfg(any(debug_assertions, leptos_debuginfo))]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
+    }
+
     impl<T: Send + Sync> From<ArcRwSignal<T>> for ArcSignal<T, SyncStorage> {
         #[track_caller]
         fn from(value: ArcRwSignal<T>) -> Self {
@@ -268,6 +282,20 @@ pub mod read {
         }
     }
 
+    impl<T, S> From<RwSignal<T, S>> for ArcSignal<T, S>
+    where
+        S: Storage<ArcRwSignal<T>> + Storage<ArcReadSignal<T>> + Storage<T>,
+    {
+        #[track_caller]
+        fn from(value: RwSignal<T, S>) -> Self {
+            Self {
+                inner: SignalTypes::ReadSignal(value.read_only().into()),
+                #[cfg(any(debug_assertions, leptos_debuginfo))]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
+    }
+
     impl<T, S> From<ArcMemo<T, S>> for ArcSignal<T, S>
     where
         S: Storage<T>,
@@ -282,6 +310,20 @@ pub mod read {
         }
     }
 
+    impl<T, S> From<Memo<T, S>> for ArcSignal<T, S>
+    where
+        S: Storage<ArcMemo<T, S>> + Storage<T>,
+    {
+        #[track_caller]
+        fn from(value: Memo<T, S>) -> Self {
+            Self {
+                inner: SignalTypes::Memo(value.into()),
+                #[cfg(any(debug_assertions, leptos_debuginfo))]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
+    }
+
     impl<T, S> DefinedAt for ArcSignal<T, S>
     where
         S: Storage<T>,
@@ -1500,7 +1542,6 @@ pub mod read {
 
     impl<T, S> ReadUntracked for MaybeProp<T, S>
     where
-        T: Clone,
         S: Storage<Option<T>> + Storage<SignalTypes<Option<T>, S>>,
     {
         type Value = ReadGuard<Option<T>, SignalReadGuard<Option<T>, S>>;

reactive_graph/tests/effect_immediate.rs

@@ -225,3 +225,38 @@ fn threaded_chaos_effect() {
     let values: Vec<_> = signals.iter().map(|s| s.get_untracked()).collect();
     println!("FINAL: {values:?}");
 }
+
+#[cfg(feature = "effects")]
+#[test]
+fn test_batch() {
+    use imports::*;
+    use reactive_graph::{effect::batch, owner::StoredValue};
+
+    let owner = Owner::new();
+    owner.set();
+
+    let a = RwSignal::new(0);
+    let b = RwSignal::new(0);
+
+    let values = StoredValue::new(Vec::new());
+
+    ImmediateEffect::new_scoped(move || {
+        println!("{} = {}", a.get(), b.get());
+        values.write_value().push((a.get(), b.get()));
+    });
+
+    a.set(1);
+    b.set(1);
+
+    batch(move || {
+        a.set(2);
+        b.set(2);
+
+        batch(move || {
+            a.set(3);
+            b.set(3);
+        });
+    });
+
+    assert_eq!(values.get_value(), vec![(0, 0), (1, 0), (1, 1), (3, 3)]);
+}

reactive_stores/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "reactive_stores"
-version = "0.2.5"
+version = "0.3.0"
 authors = ["Greg Johnston"]
 license = "MIT"
 readme = "../README.md"

reactive_stores/src/arc_field.rs

@@ -30,6 +30,8 @@ where
     defined_at: &'static Location<'static>,
     path: Arc<dyn Fn() -> StorePath + Send + Sync>,
     get_trigger: Arc<dyn Fn(StorePath) -> StoreFieldTrigger + Send + Sync>,
+    get_trigger_unkeyed:
+        Arc<dyn Fn(StorePath) -> StoreFieldTrigger + Send + Sync>,
     read: Arc<dyn Fn() -> Option<StoreFieldReader<T>> + Send + Sync>,
     pub(crate) write:
         Arc<dyn Fn() -> Option<StoreFieldWriter<T>> + Send + Sync>,
@@ -103,6 +105,10 @@ impl<T> StoreField for ArcField<T> {
         (self.get_trigger)(path)
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        (self.get_trigger_unkeyed)(path)
+    }
+
     fn path(&self) -> impl IntoIterator<Item = StorePathSegment> {
         (self.path)()
     }
@@ -132,6 +138,9 @@ where
             defined_at: Location::caller(),
             path: Arc::new(move || value.path().into_iter().collect()),
             get_trigger: Arc::new(move |path| value.get_trigger(path)),
+            get_trigger_unkeyed: Arc::new(move |path| {
+                value.get_trigger_unkeyed(path)
+            }),
             read: Arc::new(move || value.reader().map(StoreFieldReader::new)),
             write: Arc::new(move || value.writer().map(StoreFieldWriter::new)),
             keys: Arc::new(move || value.keys()),
@@ -158,6 +167,10 @@ where
                 let value = value.clone();
                 move |path| value.get_trigger(path)
             }),
+            get_trigger_unkeyed: Arc::new({
+                let value = value.clone();
+                move |path| value.get_trigger_unkeyed(path)
+            }),
             read: Arc::new({
                 let value = value.clone();
                 move || value.reader().map(StoreFieldReader::new)
@@ -202,6 +215,10 @@ where
                 let value = value.clone();
                 move |path| value.get_trigger(path)
             }),
+            get_trigger_unkeyed: Arc::new({
+                let value = value.clone();
+                move |path| value.get_trigger_unkeyed(path)
+            }),
             read: Arc::new({
                 let value = value.clone();
                 move || value.reader().map(StoreFieldReader::new)
@@ -245,6 +262,10 @@ where
                 let value = value.clone();
                 move |path| value.get_trigger(path)
             }),
+            get_trigger_unkeyed: Arc::new({
+                let value = value.clone();
+                move |path| value.get_trigger_unkeyed(path)
+            }),
             read: Arc::new({
                 let value = value.clone();
                 move || value.reader().map(StoreFieldReader::new)
@@ -289,6 +310,10 @@ where
                 let value = value.clone();
                 move |path| value.get_trigger(path)
             }),
+            get_trigger_unkeyed: Arc::new({
+                let value = value.clone();
+                move |path| value.get_trigger_unkeyed(path)
+            }),
             read: Arc::new({
                 let value = value.clone();
                 move || value.reader().map(StoreFieldReader::new)
@@ -337,6 +362,10 @@ where
                 let value = value.clone();
                 move |path| value.get_trigger(path)
             }),
+            get_trigger_unkeyed: Arc::new({
+                let value = value.clone();
+                move |path| value.get_trigger_unkeyed(path)
+            }),
             read: Arc::new({
                 let value = value.clone();
                 move || value.reader().map(StoreFieldReader::new)
@@ -368,6 +397,7 @@ impl<T> Clone for ArcField<T> {
             defined_at: self.defined_at,
             path: self.path.clone(),
             get_trigger: Arc::clone(&self.get_trigger),
+            get_trigger_unkeyed: Arc::clone(&self.get_trigger_unkeyed),
             read: Arc::clone(&self.read),
             write: Arc::clone(&self.write),
             keys: Arc::clone(&self.keys),

reactive_stores/src/deref.rs

@@ -68,6 +68,11 @@ where
     fn get_trigger(&self, path: StorePath) -> StoreFieldTrigger {
         self.inner.get_trigger(path)
     }
+
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner.get_trigger_unkeyed(path)
+    }
+
     fn path(&self) -> impl IntoIterator<Item = StorePathSegment> {
         self.inner.path()
     }

reactive_stores/src/field.rs

@@ -59,6 +59,13 @@ where
             .unwrap_or_default()
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner
+            .try_get_value()
+            .map(|inner| inner.get_trigger_unkeyed(path))
+            .unwrap_or_default()
+    }
+
     fn path(&self) -> impl IntoIterator<Item = StorePathSegment> {
         self.inner
             .try_get_value()

reactive_stores/src/iter.rs

@@ -84,6 +84,10 @@ where
         self.inner.get_trigger(path)
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner.get_trigger_unkeyed(path)
+    }
+
     fn reader(&self) -> Option<Self::Reader> {
         let inner = self.inner.reader()?;
         let index = self.index;
@@ -109,6 +113,23 @@ where
     fn keys(&self) -> Option<KeyMap> {
         self.inner.keys()
     }
+
+    fn track_field(&self) {
+        let mut full_path = self.path().into_iter().collect::<StorePath>();
+        let trigger = self.get_trigger(self.path().into_iter().collect());
+        trigger.this.track();
+        trigger.children.track();
+
+        // tracks `this` for all ancestors: i.e., it will track any change that is made
+        // directly to one of its ancestors, but not a change made to a *child* of an ancestor
+        // (which would end up with every subfield tracking its own siblings, because they are
+        // children of its parent)
+        while !full_path.is_empty() {
+            full_path.pop();
+            let inner = self.get_trigger(full_path.clone());
+            inner.this.track();
+        }
+    }
 }
 
 impl<Inner, Prev> DefinedAt for AtIndex<Inner, Prev>

reactive_stores/src/keyed.rs

@@ -110,6 +110,10 @@ where
         self.inner.get_trigger(path)
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner.get_trigger_unkeyed(path)
+    }
+
     fn reader(&self) -> Option<Self::Reader> {
         let inner = self.inner.reader()?;
         Some(Mapped::new_with_guard(inner, self.read))
@@ -432,7 +436,7 @@ where
         let this = keys
             .with_field_keys(
                 inner.clone(),
-                |keys| keys.get(&self.key),
+                |keys| (keys.get(&self.key), vec![]),
                 || self.inner.latest_keys(),
             )
             .flatten()
@@ -444,6 +448,10 @@ where
         self.inner.get_trigger(path)
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner.get_trigger_unkeyed(path)
+    }
+
     fn reader(&self) -> Option<Self::Reader> {
         let inner = self.inner.reader()?;
 
@@ -452,7 +460,7 @@ where
         let index = keys
             .with_field_keys(
                 inner_path,
-                |keys| keys.get(&self.key),
+                |keys| (keys.get(&self.key), vec![]),
                 || self.inner.latest_keys(),
             )
             .flatten()
@@ -476,7 +484,7 @@ where
         let index = keys
             .with_field_keys(
                 inner_path.clone(),
-                |keys| keys.get(&self.key),
+                |keys| (keys.get(&self.key), vec![]),
                 || self.inner.latest_keys(),
             )
             .flatten()
@@ -624,9 +632,7 @@ where
         let latest = self.latest_keys();
         keys.with_field_keys(
             inner_path,
-            |keys| {
-                keys.update(latest);
-            },
+            |keys| ((), keys.update(latest)),
             || self.latest_keys(),
         );
     }

reactive_stores/src/lib.rs

@@ -364,13 +364,18 @@ where
         })
     }
 
-    fn update(&mut self, iter: impl IntoIterator<Item = K>) {
+    fn update(
+        &mut self,
+        iter: impl IntoIterator<Item = K>,
+    ) -> Vec<(usize, StorePathSegment)> {
         let new_keys = iter
             .into_iter()
             .enumerate()
             .map(|(idx, key)| (key, idx))
             .collect::<FxHashMap<K, usize>>();
 
+        let mut index_keys = Vec::with_capacity(new_keys.len());
+
         // remove old keys and recycle the slots
         self.keys.retain(|key, old_entry| match new_keys.get(key) {
             Some(idx) => {
@@ -385,14 +390,17 @@ where
 
         // add new keys
         for (key, idx) in new_keys {
-            // the suggestion doesn't compile because we need &mut for self.next_key(),
-            // and we don't want to call that until after the check
-            #[allow(clippy::map_entry)]
-            if !self.keys.contains_key(&key) {
-                let path = self.next_key();
-                self.keys.insert(key, (path, idx));
+            match self.keys.get(&key) {
+                Some((segment, idx)) => index_keys.push((*idx, *segment)),
+                None => {
+                    let path = self.next_key();
+                    self.keys.insert(key, (path, idx));
+                    index_keys.push((idx, path));
+                }
             }
         }
+
+        index_keys
     }
 }
 
@@ -415,14 +423,20 @@ type HashMap<K, V> = send_wrapper::SendWrapper<
 
 /// A map of the keys for a keyed subfield.
 #[derive(Clone)]
-pub struct KeyMap(HashMap<StorePath, Box<dyn Any + Send + Sync>>);
+pub struct KeyMap(
+    HashMap<StorePath, Box<dyn Any + Send + Sync>>,
+    HashMap<(StorePath, usize), StorePathSegment>,
+);
 
 impl Default for KeyMap {
     fn default() -> Self {
         #[cfg(not(target_arch = "wasm32"))]
-        return Self(Default::default());
+        return Self(Default::default(), Default::default());
         #[cfg(target_arch = "wasm32")]
-        return Self(send_wrapper::SendWrapper::new(Default::default()));
+        return Self(
+            send_wrapper::SendWrapper::new(Default::default()),
+            send_wrapper::SendWrapper::new(Default::default()),
+        );
     }
 }
 
@@ -430,31 +444,70 @@ impl KeyMap {
     fn with_field_keys<K, T>(
         &self,
         path: StorePath,
-        fun: impl FnOnce(&mut FieldKeys<K>) -> T,
+        fun: impl FnOnce(&mut FieldKeys<K>) -> (T, Vec<(usize, StorePathSegment)>),
         initialize: impl FnOnce() -> Vec<K>,
     ) -> Option<T>
     where
         K: Debug + Hash + PartialEq + Eq + Send + Sync + 'static,
     {
+        let initial_keys = initialize();
+
         #[cfg(not(target_arch = "wasm32"))]
         let mut entry = self
             .0
-            .entry(path)
-            .or_insert_with(|| Box::new(FieldKeys::new(initialize())));
+            .entry(path.clone())
+            .or_insert_with(|| Box::new(FieldKeys::new(initial_keys)));
 
         #[cfg(target_arch = "wasm32")]
         let entry = if !self.0.borrow().contains_key(&path) {
-            Some(Box::new(FieldKeys::new(initialize())))
+            Some(Box::new(FieldKeys::new(initial_keys)))
         } else {
             None
         };
         #[cfg(target_arch = "wasm32")]
         let mut map = self.0.borrow_mut();
         #[cfg(target_arch = "wasm32")]
-        let entry = map.entry(path).or_insert_with(|| entry.unwrap());
+        let entry = map.entry(path.clone()).or_insert_with(|| entry.unwrap());
 
         let entry = entry.downcast_mut::<FieldKeys<K>>()?;
-        Some(fun(entry))
+        let (result, new_keys) = fun(entry);
+        if !new_keys.is_empty() {
+            for (idx, segment) in new_keys {
+                #[cfg(not(target_arch = "wasm32"))]
+                self.1.insert((path.clone(), idx), segment);
+
+                #[cfg(target_arch = "wasm32")]
+                self.1.borrow_mut().insert((path.clone(), idx), segment);
+            }
+        }
+        Some(result)
+    }
+
+    fn contains_key(&self, key: &StorePath) -> bool {
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            self.0.contains_key(key)
+        }
+
+        #[cfg(target_arch = "wasm32")]
+        {
+            self.0.borrow_mut().contains_key(key)
+        }
+    }
+
+    fn get_key_for_index(
+        &self,
+        key: &(StorePath, usize),
+    ) -> Option<StorePathSegment> {
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            self.1.get(key).as_deref().copied()
+        }
+
+        #[cfg(target_arch = "wasm32")]
+        {
+            self.1.borrow().get(key).as_deref().copied()
+        }
     }
 }
 
@@ -832,6 +885,30 @@ mod tests {
         }
     }
 
+    #[derive(Debug, Clone, Store, Patch, Default)]
+    struct Foo {
+        id: i32,
+        bar: Bar,
+    }
+
+    #[derive(Debug, Clone, Store, Patch, Default)]
+    struct Bar {
+        bar_signature: i32,
+        baz: Baz,
+    }
+
+    #[derive(Debug, Clone, Store, Patch, Default)]
+    struct Baz {
+        more_data: i32,
+        baw: Baw,
+    }
+
+    #[derive(Debug, Clone, Store, Patch, Default)]
+    struct Baw {
+        more_data: i32,
+        end: i32,
+    }
+
     #[tokio::test]
     async fn mutating_field_triggers_effect() {
         _ = any_spawner::Executor::init_tokio();
@@ -1112,30 +1189,6 @@ mod tests {
 
         _ = any_spawner::Executor::init_tokio();
 
-        #[derive(Debug, Clone, Store, Patch, Default)]
-        struct Foo {
-            id: i32,
-            bar: Bar,
-        }
-
-        #[derive(Debug, Clone, Store, Patch, Default)]
-        struct Bar {
-            bar_signature: i32,
-            baz: Baz,
-        }
-
-        #[derive(Debug, Clone, Store, Patch, Default)]
-        struct Baz {
-            more_data: i32,
-            baw: Baw,
-        }
-
-        #[derive(Debug, Clone, Store, Patch, Default)]
-        struct Baw {
-            more_data: i32,
-            end: i32,
-        }
-
         let store = Store::new(Foo {
             id: 42,
             bar: Bar {
@@ -1219,4 +1272,107 @@ mod tests {
         assert_eq!(more_data_runs.get_value(), 3);
         assert_eq!(baz_baw_end_runs.get_value(), 3);
     }
+
+    #[tokio::test]
+    async fn changing_parent_notifies_subfield() {
+        _ = any_spawner::Executor::init_tokio();
+
+        let combined_count = Arc::new(AtomicUsize::new(0));
+
+        let store = Store::new(Foo {
+            id: 42,
+            bar: Bar {
+                bar_signature: 69,
+                baz: Baz {
+                    more_data: 9999,
+                    baw: Baw {
+                        more_data: 22,
+                        end: 1112,
+                    },
+                },
+            },
+        });
+
+        let tracked_field = store.bar().baz().more_data();
+
+        Effect::new_sync({
+            let combined_count = Arc::clone(&combined_count);
+            move |prev: Option<()>| {
+                if prev.is_none() {
+                    println!("first run");
+                } else {
+                    println!("next run");
+                }
+
+                // we only track `more`, but this should still be notified
+                // when its parent fields `bar` or `baz` change
+                println!("{:?}", *tracked_field.read());
+                combined_count.fetch_add(1, Ordering::Relaxed);
+            }
+        });
+        tick().await;
+        tick().await;
+
+        store.bar().baz().set(Baz {
+            more_data: 42,
+            baw: Baw {
+                more_data: 11,
+                end: 31,
+            },
+        });
+        tick().await;
+        store.bar().set(Bar {
+            bar_signature: 23,
+            baz: Baz {
+                more_data: 32,
+                baw: Baw {
+                    more_data: 432,
+                    end: 423,
+                },
+            },
+        });
+        tick().await;
+
+        assert_eq!(combined_count.load(Ordering::Relaxed), 3);
+    }
+
+    #[tokio::test]
+    async fn changing_parent_notifies_unkeyed_child() {
+        _ = any_spawner::Executor::init_tokio();
+
+        let combined_count = Arc::new(AtomicUsize::new(0));
+
+        let store = Store::new(data());
+
+        let tracked_field = store.todos().at_unkeyed(0);
+
+        Effect::new_sync({
+            let combined_count = Arc::clone(&combined_count);
+            move |prev: Option<()>| {
+                if prev.is_none() {
+                    println!("first run");
+                } else {
+                    println!("next run");
+                }
+
+                // we only track `more`, but this should still be notified
+                // when its parent fields `bar` or `baz` change
+                println!("{:?}", *tracked_field.read());
+                combined_count.fetch_add(1, Ordering::Relaxed);
+            }
+        });
+        tick().await;
+        tick().await;
+
+        store.todos().write().pop();
+        tick().await;
+
+        store.todos().write().push(Todo {
+            label: "another one".into(),
+            completed: false,
+        });
+        tick().await;
+
+        assert_eq!(combined_count.load(Ordering::Relaxed), 3);
+    }
 }

reactive_stores/src/patch.rs

@@ -35,7 +35,7 @@ where
             // don't track the writer for the whole store
             writer.untrack();
             let mut notify = |path: &StorePath| {
-                self.triggers_for_path(path.to_owned()).notify();
+                self.triggers_for_path_unkeyed(path.to_owned()).notify();
             };
             writer.patch_field(new, &path, &mut notify);
         }

reactive_stores/src/path.rs

@@ -11,6 +11,15 @@ impl IntoIterator for StorePath {
     }
 }
 
+impl<'a> IntoIterator for &'a StorePath {
+    type Item = &'a StorePathSegment;
+    type IntoIter = std::slice::Iter<'a, StorePathSegment>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.iter()
+    }
+}
+
 impl From<Vec<StorePathSegment>> for StorePath {
     fn from(value: Vec<StorePathSegment>) -> Self {
         Self(value)
@@ -18,6 +27,16 @@ impl From<Vec<StorePathSegment>> for StorePath {
 }
 
 impl StorePath {
+    /// Creates a new path.
+    pub fn new() -> Self {
+        Self(Vec::new())
+    }
+
+    /// Creates a new path with storage capacity for `capacity` segments.
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self(Vec::with_capacity(capacity))
+    }
+
     /// Adds a new segment to the path.
     pub fn push(&mut self, segment: impl Into<StorePathSegment>) {
         self.0.push(segment.into());

reactive_stores/src/store_field.rs

@@ -26,6 +26,14 @@ pub trait StoreField: Sized {
     #[track_caller]
     fn get_trigger(&self, path: StorePath) -> StoreFieldTrigger;
 
+    /// Returns the trigger that tracks access and updates for this field.
+    ///
+    /// This uses *unkeyed* paths: i.e., if any field in the path is keyed, it will
+    /// try to look up the key for the item at the index given in the path, rather than
+    /// the keyed item.
+    #[track_caller]
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger;
+
     /// The path of this field (see [`StorePath`]).
     #[track_caller]
     fn path(&self) -> impl IntoIterator<Item = StorePathSegment>;
@@ -84,6 +92,26 @@ pub trait StoreField: Sized {
 
         triggers
     }
+
+    /// Returns triggers for the field at the given path, and all parent fields
+    fn triggers_for_path_unkeyed(&self, path: StorePath) -> Vec<ArcTrigger> {
+        // see notes on triggers_for_path() for additional comments on implementation
+
+        let trigger = self.get_trigger_unkeyed(path.clone());
+        let mut full_path = path;
+
+        let mut triggers = Vec::with_capacity(full_path.len() + 2);
+        triggers.push(trigger.this.clone());
+        triggers.push(trigger.children.clone());
+        while !full_path.is_empty() {
+            full_path.pop();
+            let inner = self.get_trigger_unkeyed(full_path.clone());
+            triggers.push(inner.children.clone());
+        }
+        triggers.reverse();
+
+        triggers
+    }
 }
 
 impl<T> StoreField for ArcStore<T>
@@ -101,6 +129,26 @@ where
         trigger
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        let orig_path = path.clone();
+
+        let mut path = StorePath::with_capacity(orig_path.len());
+        for segment in &orig_path {
+            let parent_is_keyed = self.keys.contains_key(&path);
+
+            if parent_is_keyed {
+                let key = self
+                    .keys
+                    .get_key_for_index(&(path.clone(), segment.0))
+                    .expect("could not find key for index");
+                path.push(key);
+            } else {
+                path.push(*segment);
+            }
+        }
+        self.get_trigger(path)
+    }
+
     #[track_caller]
     fn path(&self) -> impl IntoIterator<Item = StorePathSegment> {
         iter::empty()
@@ -141,6 +189,14 @@ where
             .unwrap_or_default()
     }
 
+    #[track_caller]
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner
+            .try_get_value()
+            .map(|n| n.get_trigger_unkeyed(path))
+            .unwrap_or_default()
+    }
+
     #[track_caller]
     fn path(&self) -> impl IntoIterator<Item = StorePathSegment> {
         self.inner

reactive_stores/src/subfield.rs

@@ -88,6 +88,10 @@ where
         self.inner.get_trigger(path)
     }
 
+    fn get_trigger_unkeyed(&self, path: StorePath) -> StoreFieldTrigger {
+        self.inner.get_trigger_unkeyed(path)
+    }
+
     fn reader(&self) -> Option<Self::Reader> {
         let inner = self.inner.reader()?;
         Some(Mapped::new_with_guard(inner, self.read))

router/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "leptos_router"
-version = "0.8.6"
+version = "0.8.9"
 authors = ["Greg Johnston", "Ben Wishovich"]
 license = "MIT"
 readme = "../README.md"

router/src/flat_router.rs

@@ -364,6 +364,12 @@ where
 #[derive(Debug)]
 pub(crate) struct MatchedRoute(pub String, pub AnyView);
 
+impl MatchedRoute {
+    fn branch_name(&self) -> String {
+        format!("{:?}", self.1.as_type_id())
+    }
+}
+
 impl Render for MatchedRoute {
     type State = <AnyView as Render>::State;
 
@@ -414,8 +420,9 @@ impl RenderHtml for MatchedRoute {
         mark_branches: bool,
         extra_attrs: Vec<AnyAttribute>,
     ) {
-        if mark_branches && escape {
-            buf.open_branch(&self.0);
+        let branch_name = (mark_branches && escape).then(|| self.branch_name());
+        if let Some(bn) = &branch_name {
+            buf.open_branch(bn);
         }
         self.1.to_html_with_buf(
             buf,
@@ -424,8 +431,8 @@ impl RenderHtml for MatchedRoute {
             mark_branches,
             extra_attrs,
         );
-        if mark_branches && escape {
-            buf.close_branch(&self.0);
+        if let Some(bn) = &branch_name {
+            buf.close_branch(bn);
             if *position == Position::NextChildAfterText {
                 *position = Position::NextChild;
             }
@@ -442,8 +449,9 @@ impl RenderHtml for MatchedRoute {
     ) where
         Self: Sized,
     {
-        if mark_branches && escape {
-            buf.open_branch(&self.0);
+        let branch_name = (mark_branches && escape).then(|| self.branch_name());
+        if let Some(bn) = &branch_name {
+            buf.open_branch(bn);
         }
         self.1.to_html_async_with_buf::<OUT_OF_ORDER>(
             buf,
@@ -452,8 +460,8 @@ impl RenderHtml for MatchedRoute {
             mark_branches,
             extra_attrs,
         );
-        if mark_branches && escape {
-            buf.close_branch(&self.0);
+        if let Some(bn) = &branch_name {
+            buf.close_branch(bn);
             if *position == Position::NextChildAfterText {
                 *position = Position::NextChild;
             }

router/src/location/history.rs

@@ -3,7 +3,7 @@ use crate::{hooks::use_navigate, params::ParamsMap};
 use core::fmt;
 use futures::channel::oneshot;
 use js_sys::{try_iter, Array, JsString};
-use leptos::prelude::*;
+use leptos::{ev, prelude::*};
 use or_poisoned::OrPoisoned;
 use reactive_graph::{
     signal::ArcRwSignal,
@@ -11,13 +11,12 @@ use reactive_graph::{
 };
 use std::{
     borrow::Cow,
-    boxed::Box,
     string::String,
     sync::{Arc, Mutex},
 };
 use tachys::dom::{document, window};
-use wasm_bindgen::{closure::Closure, JsCast, JsValue};
-use web_sys::{Event, UrlSearchParams};
+use wasm_bindgen::{JsCast, JsValue};
+use web_sys::UrlSearchParams;
 
 #[derive(Clone)]
 pub struct BrowserUrl {
@@ -116,7 +115,6 @@ impl LocationProvider for BrowserUrl {
     }
 
     fn init(&self, base: Option<Cow<'static, str>>) {
-        let window = window();
         let navigate = {
             let url = self.url.clone();
             let pending = Arc::clone(&self.pending_navigation);
@@ -159,37 +157,32 @@ impl LocationProvider for BrowserUrl {
 
         let handle_anchor_click =
             handle_anchor_click(base, Self::parse_with_base, navigate);
-        let closure = Closure::wrap(Box::new(move |ev: Event| {
+
+        let click_handle = window_event_listener(ev::click, move |ev| {
             if let Err(e) = handle_anchor_click(ev) {
                 #[cfg(feature = "tracing")]
                 tracing::error!("{e:?}");
                 #[cfg(not(feature = "tracing"))]
                 web_sys::console::error_1(&e);
             }
-        }) as Box<dyn FnMut(Event)>)
-        .into_js_value();
-        window
-            .add_event_listener_with_callback(
-                "click",
-                closure.as_ref().unchecked_ref(),
-            )
-            .expect(
-                "couldn't add `click` listener to `window` to handle `<a>` \
-                 clicks",
-            );
+        });
 
         // handle popstate event (forward/back navigation)
-        let cb = {
+        let popstate_cb = {
             let url = self.url.clone();
             let path_stack = self.path_stack.clone();
             let is_back = self.is_back.clone();
             move || match Self::current() {
                 Ok(new_url) => {
-                    let stack = path_stack.read_value();
+                    let mut stack = path_stack.write_value();
                     let is_navigating_back = stack.len() == 1
                         || (stack.len() >= 2
                             && stack.get(stack.len() - 2) == Some(&new_url));
 
+                    if is_navigating_back {
+                        stack.pop();
+                    }
+
                     is_back.set(is_navigating_back);
 
                     url.set(new_url);
@@ -202,14 +195,14 @@ impl LocationProvider for BrowserUrl {
                 }
             }
         };
-        let closure =
-            Closure::wrap(Box::new(cb) as Box<dyn Fn()>).into_js_value();
-        window
-            .add_event_listener_with_callback(
-                "popstate",
-                closure.as_ref().unchecked_ref(),
-            )
-            .expect("couldn't add `popstate` listener to `window`");
+
+        let popstate_handle =
+            window_event_listener(ev::popstate, move |_| popstate_cb());
+
+        on_cleanup(|| {
+            click_handle.remove();
+            popstate_handle.remove();
+        });
     }
 
     fn ready_to_complete(&self) {
@@ -221,6 +214,13 @@ impl LocationProvider for BrowserUrl {
     fn complete_navigation(&self, loc: &LocationChange) {
         let history = window().history().unwrap();
 
+        let current_path = self
+            .path_stack
+            .read_value()
+            .last()
+            .map(|url| url.to_full_path());
+        let add_to_stack = current_path.as_ref() != Some(&loc.value);
+
         if loc.replace {
             history
                 .replace_state_with_url(
@@ -229,7 +229,7 @@ impl LocationProvider for BrowserUrl {
                     Some(&loc.value),
                 )
                 .unwrap();
-        } else {
+        } else if add_to_stack {
             // push the "forward direction" marker
             let state = &loc.state.to_js_value();
             history
@@ -240,7 +240,9 @@ impl LocationProvider for BrowserUrl {
         // add this URL to the "path stack" for detecting back navigations, and
         // unset "navigating back" state
         if let Ok(url) = Self::current() {
-            self.path_stack.write_value().push(url);
+            if add_to_stack {
+                self.path_stack.write_value().push(url);
+            }
             self.is_back.set(false);
         }
 

router/src/location/mod.rs

@@ -14,7 +14,7 @@ use send_wrapper::SendWrapper;
 use std::{borrow::Cow, future::Future};
 use tachys::dom::window;
 use wasm_bindgen::{JsCast, JsValue};
-use web_sys::{Event, HtmlAnchorElement, MouseEvent};
+use web_sys::{HtmlAnchorElement, MouseEvent};
 
 mod history;
 mod server;
@@ -300,15 +300,14 @@ pub(crate) fn handle_anchor_click<NavFn, NavFut>(
     router_base: Option<Cow<'static, str>>,
     parse_with_base: fn(&str, &str) -> Result<Url, JsValue>,
     navigate: NavFn,
-) -> Box<dyn Fn(Event) -> Result<(), JsValue>>
+) -> Box<dyn Fn(MouseEvent) -> Result<(), JsValue>>
 where
     NavFn: Fn(Url, LocationChange) -> NavFut + 'static,
     NavFut: Future<Output = ()> + 'static,
 {
     let router_base = router_base.unwrap_or_default();
 
-    Box::new(move |ev: Event| {
-        let ev = ev.unchecked_into::<MouseEvent>();
+    Box::new(move |ev: MouseEvent| {
         let origin = window().location().origin()?;
         if ev.default_prevented()
             || ev.button() != 0

router/src/matching/horizontal/tuples.rs

@@ -4,7 +4,6 @@ macro_rules! tuples {
     ($first:ident => $($ty:ident),*) => {
         impl<$first, $($ty),*> PossibleRouteMatch for ($first, $($ty,)*)
         where
-            Self: core::fmt::Debug,
             $first: PossibleRouteMatch,
 			$($ty: PossibleRouteMatch),*,
         {

router/src/nested_router.rs

@@ -26,7 +26,7 @@ use reactive_graph::{
     computed::{ArcMemo, ScopedFuture},
     owner::{provide_context, use_context, Owner},
     signal::{ArcRwSignal, ArcTrigger},
-    traits::{Get, GetUntracked, Notify, ReadUntracked, Set, Track},
+    traits::{Get, GetUntracked, Notify, ReadUntracked, Set, Track, Write},
     transition::AsyncTransition,
     wrappers::write::SignalSetter,
 };
@@ -119,6 +119,7 @@ where
                     base,
                     &mut loaders,
                     &mut outlets,
+                    &outer_owner,
                 );
                 drop(url);
 
@@ -159,13 +160,14 @@ where
             }
             return;
         }
+
         // since the path didn't match, we'll update the retained path for future diffing
         state.path.clear();
         state.path.push_str(url_snapshot.path());
 
         let new_match = self.routes.match_route(url_snapshot.path());
 
-        state.current_url.set(url_snapshot);
+        *state.current_url.write_untracked() = url_snapshot;
 
         match new_match {
             None => {
@@ -192,6 +194,7 @@ where
                     &mut state.outlets,
                     self.set_is_routing.is_some(),
                     0,
+                    &self.outer_owner,
                 );
 
                 let (abort_handle, abort_registration) =
@@ -369,6 +372,7 @@ where
                         base,
                         &mut loaders,
                         &mut outlets,
+                        &outer_owner,
                     );
 
                     // outlets will not send their views if the loaders are never polled
@@ -422,8 +426,16 @@ where
                     base,
                     &mut loaders,
                     &mut outlets,
+                    &outer_owner,
                 );
 
+                let preload_owners = outlets
+                    .iter()
+                    .map(|o| o.preload_owner.clone())
+                    .collect::<Vec<_>>();
+                outer_owner
+                    .with(|| Owner::on_cleanup(move || drop(preload_owners)));
+
                 // outlets will not send their views if the loaders are never polled
                 // the loaders are async so that they can lazy-load routes in the browser,
                 // but they should always be synchronously available on the server
@@ -475,6 +487,7 @@ where
                         base,
                         &mut loaders,
                         &mut outlets,
+                        &outer_owner,
                     );
                     drop(url);
 
@@ -530,6 +543,7 @@ where
                         base,
                         &mut loaders,
                         &mut outlets,
+                        &outer_owner,
                     );
                     drop(url);
 
@@ -566,6 +580,7 @@ pub(crate) struct RouteContext {
     base: Option<Oco<'static, str>>,
     view_fn: Arc<Mutex<OutletViewFn>>,
     owner: Arc<Mutex<Option<Owner>>>,
+    preload_owner: Owner,
     child: ChildRoute,
 }
 
@@ -597,6 +612,7 @@ impl Clone for RouteContext {
             view_fn: Arc::clone(&self.view_fn),
             owner: Arc::clone(&self.owner),
             child: self.child.clone(),
+            preload_owner: self.preload_owner.clone(),
         }
     }
 }
@@ -608,6 +624,7 @@ trait AddNestedRoute {
         base: Option<Oco<'static, str>>,
         loaders: &mut Vec<Pin<Box<dyn Future<Output = ArcTrigger>>>>,
         outlets: &mut Vec<RouteContext>,
+        outer_owner: &Owner,
     );
 
     #[allow(clippy::too_many_arguments)]
@@ -621,6 +638,7 @@ trait AddNestedRoute {
         outlets: &mut Vec<RouteContext>,
         set_is_routing: bool,
         level: u8,
+        outer_owner: &Owner,
     ) -> u8;
 }
 
@@ -634,6 +652,7 @@ where
         base: Option<Oco<'static, str>>,
         loaders: &mut Vec<Pin<Box<dyn Future<Output = ArcTrigger>>>>,
         outlets: &mut Vec<RouteContext>,
+        outer_owner: &Owner,
     ) {
         let orig_url = url;
 
@@ -701,6 +720,7 @@ where
             base: base.clone(),
             child: ChildRoute(Arc::new(Mutex::new(None))),
             owner: Arc::new(Mutex::new(None)),
+            preload_owner: outer_owner.child(),
         };
         if !outlets.is_empty() {
             let prev_index = outlets.len().saturating_sub(1);
@@ -725,7 +745,15 @@ where
                 provide_context(params.clone());
                 provide_context(url.clone());
                 provide_context(matched.clone());
-                view.preload().await;
+                outlet
+                    .preload_owner
+                    .with(|| {
+                        provide_context(params.clone());
+                        provide_context(url.clone());
+                        provide_context(matched.clone());
+                        ScopedFuture::new(view.preload())
+                    })
+                    .await;
                 let child = outlet.child.clone();
                 *view_fn.lock().or_poisoned() =
                     Box::new(move |owner_where_used| {
@@ -772,7 +800,13 @@ where
         // this is important because to build the view, we need access to the outlet
         // and the outlet will be returned from building this child
         if let Some(child) = child {
-            child.build_nested_route(orig_url, base, loaders, outlets);
+            child.build_nested_route(
+                orig_url,
+                base,
+                loaders,
+                outlets,
+                outer_owner,
+            );
         }
     }
 
@@ -787,6 +821,7 @@ where
         outlets: &mut Vec<RouteContext>,
         set_is_routing: bool,
         level: u8,
+        outer_owner: &Owner,
     ) -> u8 {
         let (parent_params, parent_matches): (Vec<_>, Vec<_>) = outlets
             .iter()
@@ -803,7 +838,13 @@ where
         match current {
             // if there's nothing currently in the routes at this point, build from here
             None => {
-                self.build_nested_route(url, base, preloaders, outlets);
+                self.build_nested_route(
+                    url,
+                    base,
+                    preloaders,
+                    outlets,
+                    outer_owner,
+                );
                 level
             }
             Some(current) => {
@@ -843,6 +884,10 @@ where
                         &mut current.matched,
                         ArcRwSignal::new(new_match),
                     );
+                    let old_preload_owner = mem::replace(
+                        &mut current.preload_owner,
+                        outer_owner.child(),
+                    );
                     let matched_including_parents = {
                         ArcMemo::new({
                             let matched = current.matched.clone();
@@ -885,11 +930,26 @@ where
                         let child = outlet.child.clone();
                         async move {
                             let child = child.clone();
-                            if set_is_routing {
-                                AsyncTransition::run(|| view.preload()).await;
-                            } else {
-                                view.preload().await;
-                            }
+                            outlet
+                                .preload_owner
+                                .with(|| {
+                                    provide_context(
+                                        params_including_parents.clone(),
+                                    );
+                                    provide_context(url.clone());
+                                    provide_context(matched.clone());
+                                    ScopedFuture::new(async {
+                                        if set_is_routing {
+                                            AsyncTransition::run(|| {
+                                                view.preload()
+                                            })
+                                            .await;
+                                        } else {
+                                            view.preload().await;
+                                        }
+                                    })
+                                })
+                                .await;
                             *view_fn.lock().or_poisoned() =
                                 Box::new(move |owner_where_used| {
                                     let prev_owner = route_owner
@@ -938,6 +998,7 @@ where
                             drop(old_params);
                             drop(old_url);
                             drop(old_matched);
+                            drop(old_preload_owner);
                             trigger
                         }
                     })));
@@ -948,8 +1009,13 @@ where
 
                     // if this children has matches, then rebuild the lower section of the tree
                     if let Some(child) = child {
-                        child
-                            .build_nested_route(url, base, preloaders, outlets);
+                        child.build_nested_route(
+                            url,
+                            base,
+                            preloaders,
+                            outlets,
+                            outer_owner,
+                        );
                     } else {
                         *outlets[*items].child.0.lock().or_poisoned() = None;
                     }
@@ -973,6 +1039,7 @@ where
                         outlets,
                         set_is_routing,
                         level + 1,
+                        outer_owner,
                     )
                 } else {
                     *current.child.0.lock().or_poisoned() = None;

router/src/static_routes.rs

@@ -369,7 +369,7 @@ impl ResolvedStaticPath {
                             eprintln!("{e}");
                         }
                     }
-                    owner.unset();
+                    owner.unset_with_forced_cleanup();
                 }
             }
         });

router_macro/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "leptos_router_macro"
-version = "0.8.5"
+version = "0.8.6"
 authors = ["Greg Johnston", "Ben Wishovich"]
 license = "MIT"
 readme = "../README.md"

router_macro/src/lib.rs

@@ -7,7 +7,7 @@
 use proc_macro::{TokenStream, TokenTree};
 use proc_macro2::Span;
 use proc_macro_error2::{abort, proc_macro_error, set_dummy};
-use quote::{quote, ToTokens};
+use quote::{format_ident, quote, ToTokens};
 use syn::{
     spanned::Spanned, FnArg, Ident, ImplItem, ItemImpl, Path, Type, TypePath,
 };
@@ -267,10 +267,7 @@ fn lazy_route_impl(
     };
     let lazy_view_ident =
         Ident::new(&format!("__{ty_name_to_snake}_View"), im.self_ty.span());
-    let preload_lazy_view_ident = Ident::new(
-        &format!("__preload_{lazy_view_ident}"),
-        lazy_view_ident.span(),
-    );
+    let preload_ident = format_ident!("__preload_{lazy_view_ident}");
 
     im.items.push(
         syn::parse::<ImplItem>(
@@ -280,7 +277,7 @@ fn lazy_route_impl(
                     // we don't split routes for wasm32 ssr
                     // but we don't require a `hydrate`/`csr` feature on leptos_router
                     #[cfg(target_arch = "wasm32")]
-                    #preload_lazy_view_ident().await;
+                    #preload_ident().await;
                 }
             }
             .into(),

server_fn/Cargo.toml

@@ -5,7 +5,7 @@ license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"
 description = "RPC for any web framework."
 readme = "../README.md"
-version = "0.8.6"
+version = "0.8.8"
 rust-version.workspace = true
 edition.workspace = true
 
@@ -64,6 +64,7 @@ http-body-util = { optional = true, workspace = true, default-features = true }
 rkyv = { optional = true, workspace = true, default-features = true }
 rmp-serde = { optional = true, workspace = true, default-features = true }
 base64 = { workspace = true, default-features = true }
+bitcode = { optional = true, workspace = true, default-features = true }
 
 # client
 gloo-net = { optional = true, workspace = true, default-features = true }
@@ -126,6 +127,7 @@ cbor = ["dep:ciborium"]
 rkyv = ["dep:rkyv"]
 msgpack = ["dep:rmp-serde"]
 postcard = ["dep:postcard"]
+bitcode = ["dep:bitcode"]
 default-tls = ["reqwest?/default-tls"]
 rustls = ["reqwest?/rustls-tls", "tokio-tungstenite?/rustls"]
 reqwest = ["dep:reqwest", "dep:tokio-tungstenite", "dep:tokio"]

server_fn/src/codec/bitcode.rs

@@ -0,0 +1,49 @@
+use super::{Patch, Post, Put};
+use crate::{ContentType, Decodes, Encodes, Format, FormatType};
+use bytes::Bytes;
+
+/// Serializes and deserializes with [`bitcode`].
+pub struct BitcodeEncoding;
+
+impl ContentType for BitcodeEncoding {
+    const CONTENT_TYPE: &'static str = "application/bitcode";
+}
+
+impl FormatType for BitcodeEncoding {
+    const FORMAT_TYPE: Format = Format::Binary;
+}
+
+impl<T> Encodes<T> for BitcodeEncoding
+where
+    T: bitcode::Encode,
+{
+    type Error = std::convert::Infallible;
+
+    fn encode(value: &T) -> Result<Bytes, Self::Error> {
+        Ok(Bytes::from(bitcode::encode(value)))
+    }
+}
+
+impl<T> Decodes<T> for BitcodeEncoding
+where
+    T: bitcode::DecodeOwned,
+{
+    type Error = bitcode::Error;
+
+    fn decode(bytes: Bytes) -> Result<T, Self::Error> {
+        bitcode::decode(bytes.as_ref())
+    }
+}
+
+/// Pass arguments and receive responses using `bitcode` in a `POST` request.
+pub type Bitcode = Post<BitcodeEncoding>;
+
+/// Pass arguments and receive responses using `bitcode` in the body of a `PATCH` request.
+/// **Note**: Browser support for `PATCH` requests without JS/WASM may be poor.
+/// Consider using a `POST` request if functionality without JS/WASM is required.
+pub type PatchBitcode = Patch<BitcodeEncoding>;
+
+/// Pass arguments and receive responses using `bitcode` in the body of a `PUT` request.
+/// **Note**: Browser support for `PUT` requests without JS/WASM may be poor.
+/// Consider using a `POST` request if functionality without JS/WASM is required.
+pub type PutBitcode = Put<BitcodeEncoding>;

server_fn/src/codec/mod.rs

@@ -50,6 +50,11 @@ mod postcard;
 #[cfg(feature = "postcard")]
 pub use postcard::*;
 
+#[cfg(feature = "bitcode")]
+mod bitcode;
+#[cfg(feature = "bitcode")]
+pub use bitcode::*;
+
 mod patch;
 pub use patch::*;
 mod post;

server_fn/src/error.rs

@@ -568,7 +568,7 @@ pub trait FromServerFnError: std::fmt::Debug + Sized + 'static {
     /// Converts a [`ServerFnErrorErr`] into the application-specific custom error type.
     fn from_server_fn_error(value: ServerFnErrorErr) -> Self;
 
-    /// Converts the custom error type to a [`String`].
+    /// Serializes the custom error type to bytes, according to the encoding given by `Self::Encoding`.
     fn ser(&self) -> Bytes {
         Self::Encoder::encode(self).unwrap_or_else(|e| {
             Self::Encoder::encode(&Self::from_server_fn_error(
@@ -581,7 +581,7 @@ pub trait FromServerFnError: std::fmt::Debug + Sized + 'static {
         })
     }
 
-    /// Deserializes the custom error type from a [`&str`].
+    /// Deserializes the custom error type, according to the encoding given by `Self::Encoding`.
     fn de(data: Bytes) -> Self {
         Self::Encoder::decode(data).unwrap_or_else(|e| {
             ServerFnErrorErr::Deserialization(e.to_string()).into_app_error()

server_fn/src/lib.rs

@@ -133,6 +133,8 @@ pub use ::bytes as bytes_export;
 #[doc(hidden)]
 pub use ::http as http_export;
 use base64::{engine::general_purpose::STANDARD_NO_PAD, DecodeError, Engine};
+#[cfg(feature = "bitcode")]
+pub use bitcode;
 // re-exported to make it possible to implement a custom Client without adding a separate
 // dependency on `bytes`
 pub use bytes::Bytes;
@@ -307,16 +309,18 @@ pub trait ServerFn: Send + Sized {
                     .await
                     .map(|res| (res, None))
                     .unwrap_or_else(|e| {
-                        (
+                        let mut response =
                             <<Self as ServerFn>::Server as crate::Server<
                                 Self::Error,
                                 Self::InputStreamError,
                                 Self::OutputStreamError,
                             >>::Response::error_response(
                                 Self::PATH, e.ser()
-                            ),
-                            Some(e),
-                        )
+                            );
+                        let content_type =
+                    <Self::Error as FromServerFnError>::Encoder::CONTENT_TYPE;
+                        response.content_type(content_type);
+                        (response, Some(e))
                     });
 
             // if it accepts HTML, we'll redirect to the Referer

server_fn/src/middleware/mod.rs

@@ -72,6 +72,10 @@ mod axum {
             let inner = self.call(req);
             Box::pin(async move {
                 inner.await.unwrap_or_else(|e| {
+                    // TODO: This does not set the Content-Type on the response. Doing so will
+                    //  require a breaking change in order to get the correct encoding from the
+                    //  error's `FromServerFnError::Encoder::CONTENT_TYPE` impl.
+                    //  Note: This only applies to middleware errors.
                     let err =
                         ser(ServerFnErrorErr::MiddlewareError(e.to_string()));
                     Response::<Body>::error_response(&path, err)
@@ -149,6 +153,10 @@ mod actix {
             let inner = self.call(req);
             Box::pin(async move {
                 inner.await.unwrap_or_else(|e| {
+                    // TODO: This does not set the Content-Type on the response. Doing so will
+                    //  require a breaking change in order to get the correct encoding from the
+                    //  error's `FromServerFnError::Encoder::CONTENT_TYPE` impl.
+                    //  Note: This only applies to middleware errors.
                     let err =
                         ser(ServerFnErrorErr::MiddlewareError(e.to_string()));
                     ActixResponse::error_response(&path, err).take()

server_fn/src/response/actix.rs

@@ -5,7 +5,7 @@ use crate::error::{
 use actix_web::{
     http::{
         header,
-        header::{HeaderValue, LOCATION},
+        header::{HeaderValue, CONTENT_TYPE, LOCATION},
         StatusCode,
     },
     HttpResponse,
@@ -80,6 +80,12 @@ impl Res for ActixResponse {
         ))
     }
 
+    fn content_type(&mut self, content_type: &str) {
+        if let Ok(content_type) = HeaderValue::from_str(content_type) {
+            self.0.headers_mut().insert(CONTENT_TYPE, content_type);
+        }
+    }
+
     fn redirect(&mut self, path: &str) {
         if let Ok(path) = HeaderValue::from_str(path) {
             *self.0.status_mut() = StatusCode::FOUND;

server_fn/src/response/generic.rs

@@ -100,6 +100,13 @@ impl Res for Response<Body> {
             .unwrap()
     }
 
+    fn content_type(&mut self, content_type: &str) {
+        if let Ok(content_type) = HeaderValue::from_str(content_type) {
+            self.headers_mut()
+                .insert(header::CONTENT_TYPE, content_type);
+        }
+    }
+
     fn redirect(&mut self, path: &str) {
         if let Ok(path) = HeaderValue::from_str(path) {
             self.headers_mut().insert(header::LOCATION, path);

server_fn/src/response/http.rs

@@ -60,6 +60,13 @@ impl Res for Response<Body> {
             .unwrap()
     }
 
+    fn content_type(&mut self, content_type: &str) {
+        if let Ok(content_type) = HeaderValue::from_str(content_type) {
+            self.headers_mut()
+                .insert(header::CONTENT_TYPE, content_type);
+        }
+    }
+
     fn redirect(&mut self, path: &str) {
         if let Ok(path) = HeaderValue::from_str(path) {
             self.headers_mut().insert(header::LOCATION, path);

server_fn/src/response/mod.rs

@@ -37,9 +37,14 @@ where
 
 /// Represents the response as created by the server;
 pub trait Res {
-    /// Converts an error into a response, with a `500` status code and the error text as its body.
+    /// Converts an error into a response, with a `500` status code and the error as its body.
     fn error_response(path: &str, err: Bytes) -> Self;
-
+    /// Set the `Content-Type` header for the response.
+    fn content_type(&mut self, #[allow(unused_variables)] content_type: &str) {
+        // TODO 0.9: remove this method and default implementation. It is only included here
+        //  to allow setting the `Content-Type` header for error responses without requiring a
+        //  semver-incompatible change.
+    }
     /// Redirect the response by setting a 302 code and Location header.
     fn redirect(&mut self, path: &str);
 }
@@ -103,6 +108,10 @@ impl Res for BrowserMockRes {
         unreachable!()
     }
 
+    fn content_type(&mut self, _content_type: &str) {
+        unreachable!()
+    }
+
     fn redirect(&mut self, _path: &str) {
         unreachable!()
     }

server_fn/tests/server_macro.rs

@@ -10,7 +10,8 @@
         feature = "multipart",
         feature = "serde-lite",
         feature = "cbor",
-        feature = "msgpack"
+        feature = "msgpack",
+        feature = "bitcode",
     ))
 ))]
 

server_fn_macro/Cargo.toml

@@ -5,7 +5,7 @@ license = "MIT"
 repository = "https://github.com/leptos-rs/leptos"
 description = "RPC for any web framework."
 readme = "../README.md"
-version = "0.8.7"
+version = "0.8.8"
 edition.workspace = true
 
 [dependencies]

server_fn_macro/src/lib.rs

@@ -331,6 +331,7 @@ impl ServerFnCall {
         enum PathInfo {
             Serde,
             Rkyv,
+            Bitcode,
             None,
         }
 
@@ -341,6 +342,12 @@ impl ServerFnCall {
                     Clone, #server_fn_path::rkyv::Archive, #server_fn_path::rkyv::Serialize, #server_fn_path::rkyv::Deserialize
                 },
             ),
+            Some("Bitcode") => (
+                PathInfo::Bitcode,
+                quote! {
+                    Clone, #server_fn_path::bitcode::Encode, #server_fn_path::bitcode::Decode
+                },
+            ),
             Some("MultipartFormData")
             | Some("Streaming")
             | Some("StreamingText") => (PathInfo::None, quote! {}),
@@ -376,6 +383,7 @@ impl ServerFnCall {
                     #[serde(crate = #serde_path)]
                 }
             }
+            PathInfo::Bitcode => quote! {},
             PathInfo::Rkyv => quote! {},
             PathInfo::None => quote! {},
         };

tachys/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tachys"
-version = "0.2.7"
+version = "0.2.10"
 authors = ["Greg Johnston"]
 license = "MIT"
 readme = "../README.md"
@@ -179,6 +179,7 @@ default = ["testing"]
 delegation = []                                                       # enables event delegation
 error-hook = []
 hydrate = []
+lazy = []
 islands = ["dep:serde", "dep:serde_json"]
 ssr = []
 oco = ["dep:oco_ref"]

tachys/src/html/attribute/any_attribute.rs

@@ -1,6 +1,10 @@
 use super::{Attribute, NextAttribute};
-use crate::erased::{Erased, ErasedLocal};
-use std::{any::TypeId, fmt::Debug};
+use crate::{
+    erased::{Erased, ErasedLocal},
+    html::attribute::NamedAttributeKey,
+    renderer::{dom::Element, Rndr},
+};
+use std::{any::TypeId, fmt::Debug, mem};
 #[cfg(feature = "ssr")]
 use std::{future::Future, pin::Pin};
 
@@ -25,6 +29,7 @@ pub struct AnyAttribute {
     resolve: fn(Erased) -> Pin<Box<dyn Future<Output = AnyAttribute> + Send>>,
     #[cfg(feature = "ssr")]
     dry_resolve: fn(&mut Erased),
+    keys: fn(&Erased) -> Vec<NamedAttributeKey>,
 }
 
 impl Clone for AnyAttribute {
@@ -44,6 +49,7 @@ pub struct AnyAttributeState {
     type_id: TypeId,
     state: ErasedLocal,
     el: crate::renderer::types::Element,
+    keys: Vec<NamedAttributeKey>,
 }
 
 /// Converts an [`Attribute`] into [`AnyAttribute`].
@@ -84,6 +90,7 @@ where
         ) -> AnyAttributeState {
             AnyAttributeState {
                 type_id: TypeId::of::<T>(),
+                keys: value.get_ref::<T>().keys(),
                 state: ErasedLocal::new(value.into_inner::<T>().build(&el)),
                 el,
             }
@@ -96,6 +103,7 @@ where
         ) -> AnyAttributeState {
             AnyAttributeState {
                 type_id: TypeId::of::<T>(),
+                keys: value.get_ref::<T>().keys(),
                 state: ErasedLocal::new(
                     value.into_inner::<T>().hydrate::<true>(&el),
                 ),
@@ -110,6 +118,7 @@ where
         ) -> AnyAttributeState {
             AnyAttributeState {
                 type_id: TypeId::of::<T>(),
+                keys: value.get_ref::<T>().keys(),
                 state: ErasedLocal::new(
                     value.into_inner::<T>().hydrate::<true>(&el),
                 ),
@@ -140,6 +149,12 @@ where
             async move {value.into_inner::<T>().resolve().await.into_any_attr()}.boxed()
         }
 
+        fn keys<T: Attribute + 'static>(
+            value: &Erased,
+        ) -> Vec<NamedAttributeKey> {
+            value.get_ref::<T>().keys()
+        }
+
         let value = self.into_cloneable_owned();
         AnyAttribute {
             type_id: TypeId::of::<T::CloneableOwned>(),
@@ -158,6 +173,7 @@ where
             resolve: resolve::<T::CloneableOwned>,
             #[cfg(feature = "ssr")]
             dry_resolve: dry_resolve::<T::CloneableOwned>,
+            keys: keys::<T::CloneableOwned>,
         }
     }
 }
@@ -268,6 +284,10 @@ impl Attribute for AnyAttribute {
              enabled."
         );
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        (self.keys)(&self.value)
+    }
 }
 
 impl NextAttribute for Vec<AnyAttribute> {
@@ -286,7 +306,7 @@ impl Attribute for Vec<AnyAttribute> {
     const MIN_LENGTH: usize = 0;
 
     type AsyncOutput = Vec<AnyAttribute>;
-    type State = Vec<AnyAttributeState>;
+    type State = (Element, Vec<AnyAttributeState>);
     type Cloneable = Vec<AnyAttribute>;
     type CloneableOwned = Vec<AnyAttribute>;
 
@@ -321,13 +341,19 @@ impl Attribute for Vec<AnyAttribute> {
     ) -> Self::State {
         #[cfg(feature = "hydrate")]
         if FROM_SERVER {
-            self.into_iter()
-                .map(|attr| attr.hydrate::<true>(el))
-                .collect()
+            (
+                el.clone(),
+                self.into_iter()
+                    .map(|attr| attr.hydrate::<true>(el))
+                    .collect(),
+            )
         } else {
-            self.into_iter()
-                .map(|attr| attr.hydrate::<false>(el))
-                .collect()
+            (
+                el.clone(),
+                self.into_iter()
+                    .map(|attr| attr.hydrate::<false>(el))
+                    .collect(),
+            )
         }
         #[cfg(not(feature = "hydrate"))]
         {
@@ -340,13 +366,34 @@ impl Attribute for Vec<AnyAttribute> {
     }
 
     fn build(self, el: &crate::renderer::types::Element) -> Self::State {
-        self.into_iter().map(|attr| attr.build(el)).collect()
+        (
+            el.clone(),
+            self.into_iter().map(|attr| attr.build(el)).collect(),
+        )
     }
 
     fn rebuild(self, state: &mut Self::State) {
-        for (attr, state) in self.into_iter().zip(state.iter_mut()) {
-            attr.rebuild(state)
+        let (el, state) = state;
+        for old in mem::take(state) {
+            for key in old.keys {
+                match key {
+                    NamedAttributeKey::InnerHtml => {
+                        Rndr::set_inner_html(&old.el, "");
+                    }
+                    NamedAttributeKey::Property(prop_name) => {
+                        Rndr::set_property(
+                            &old.el,
+                            &prop_name,
+                            &wasm_bindgen::JsValue::UNDEFINED,
+                        );
+                    }
+                    NamedAttributeKey::Attribute(key) => {
+                        Rndr::remove_attribute(&old.el, &key);
+                    }
+                }
+            }
         }
+        *state = self.into_iter().map(|s| s.build(el)).collect();
     }
 
     fn into_cloneable(self) -> Self::Cloneable {
@@ -385,4 +432,8 @@ impl Attribute for Vec<AnyAttribute> {
              enabled."
         );
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        self.iter().flat_map(|s| s.keys()).collect()
+    }
 }

tachys/src/html/attribute/custom.rs

@@ -4,7 +4,7 @@ use super::{
 use crate::{
     html::attribute::{
         maybe_next_attr_erasure_macros::next_attr_combine, Attribute,
-        AttributeValue,
+        AttributeValue, NamedAttributeKey,
     },
     view::{add_attr::AddAnyAttr, Position, ToTemplate},
 };
@@ -112,6 +112,12 @@ where
             value: self.value.resolve().await,
         }
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        vec![NamedAttributeKey::Attribute(
+            self.key.as_ref().to_string().into(),
+        )]
+    }
 }
 
 impl<K, V> NextAttribute for CustomAttr<K, V>

tachys/src/html/attribute/global.rs

@@ -205,6 +205,14 @@ where
         self.add_any_attr(enterkeyhint(value))
     }
 
+    /// The `exportparts` attribute enables the sharing of parts of an element's shadow DOM with a containing document.
+    fn exportparts(
+        self,
+        value: V,
+    ) -> <Self as AddAnyAttr>::Output<Attr<Exportparts, V>> {
+        self.add_any_attr(exportparts(value))
+    }
+
     /// The `hidden` global attribute is a Boolean attribute indicating that the element is not yet, or is no longer, relevant.
     fn hidden(self, value: V) -> <Self as AddAnyAttr>::Output<Attr<Hidden, V>> {
         self.add_any_attr(hidden(value))

tachys/src/html/attribute/mod.rs

@@ -15,7 +15,7 @@ pub use key::*;
 use maybe_next_attr_erasure_macros::{
     next_attr_combine, next_attr_output_type,
 };
-use std::{fmt::Debug, future::Future};
+use std::{borrow::Cow, fmt::Debug, future::Future};
 pub use value::*;
 
 /// Defines an attribute: anything that can modify an element.
@@ -75,6 +75,25 @@ pub trait Attribute: NextAttribute + Send {
 
     /// “Resolves” this into a type that is not waiting for any asynchronous data.
     fn resolve(self) -> impl Future<Output = Self::AsyncOutput> + Send;
+
+    /// Returns a set of attribute keys, associated with this attribute, if any.
+    ///
+    /// This is only used to manage the removal of type-erased attributes, when needed.
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        // TODO: remove default implementation in 0.9, or fix this whole approach
+        // by making it easier to remove attributes
+        vec![]
+    }
+}
+
+/// An attribute key can be used to remove an attribute from an element.
+pub enum NamedAttributeKey {
+    /// An ordinary attribute.
+    Attribute(Cow<'static, str>),
+    /// A DOM property.
+    Property(Cow<'static, str>),
+    /// The `inner_html` pseudo-attribute.
+    InnerHtml,
 }
 
 /// Adds another attribute to this one, returning a new attribute.
@@ -133,6 +152,10 @@ impl Attribute for () {
     fn dry_resolve(&mut self) {}
 
     async fn resolve(self) -> Self::AsyncOutput {}
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        vec![]
+    }
 }
 
 impl NextAttribute for () {
@@ -249,6 +272,10 @@ where
     async fn resolve(self) -> Self::AsyncOutput {
         Attr(self.0, self.1.resolve().await)
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        vec![NamedAttributeKey::Attribute(K::KEY.into())]
+    }
 }
 
 impl<K, V> NextAttribute for Attr<K, V>
@@ -353,6 +380,14 @@ macro_rules! impl_attr_for_tuples {
                     $($ty.resolve()),*
                 )
             }
+
+            fn keys(&self) -> Vec<NamedAttributeKey> {
+                #[allow(non_snake_case)]
+                let ($first, $($ty,)*) = &self;
+                let mut buf = $first.keys();
+                $(buf.extend($ty.keys());)*
+                buf
+            }
         }
 
         impl<$first, $($ty),*> NextAttribute for ($first, $($ty,)*)
@@ -462,6 +497,14 @@ macro_rules! impl_attr_for_tuples_truncate_additional {
                     $($ty.resolve()),*
                 )
             }
+
+            fn keys(&self) -> Vec<NamedAttributeKey> {
+                #[allow(non_snake_case)]
+                let ($first, $($ty,)*) = &self;
+                let mut buf = $first.keys();
+                $(buf.extend($ty.keys());)*
+                buf
+            }
         }
 
         impl<$first, $($ty),*> NextAttribute for ($first, $($ty,)*)
@@ -538,6 +581,10 @@ where
     async fn resolve(self) -> Self::AsyncOutput {
         (self.0.resolve().await,)
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        self.0.keys()
+    }
 }
 
 impl<A> NextAttribute for (A,)

tachys/src/html/class.rs

@@ -1,6 +1,6 @@
 use super::attribute::{
     maybe_next_attr_erasure_macros::next_attr_output_type, Attribute,
-    NextAttribute,
+    NamedAttributeKey, NextAttribute,
 };
 use crate::{
     html::attribute::maybe_next_attr_erasure_macros::next_attr_combine,
@@ -97,6 +97,10 @@ where
             class: self.class.resolve().await,
         }
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        vec![NamedAttributeKey::Attribute("class".into())]
+    }
 }
 
 impl<C> NextAttribute for Class<C>

tachys/src/html/directive.rs

@@ -3,7 +3,9 @@ use super::attribute::{
     NextAttribute,
 };
 use crate::{
-    html::attribute::maybe_next_attr_erasure_macros::next_attr_combine,
+    html::attribute::{
+        maybe_next_attr_erasure_macros::next_attr_combine, NamedAttributeKey,
+    },
     prelude::AddAnyAttr,
     view::{Position, ToTemplate},
 };
@@ -160,6 +162,10 @@ where
     async fn resolve(self) -> Self::AsyncOutput {
         self
     }
+
+    fn keys(&self) -> Vec<NamedAttributeKey> {
+        vec![]
+    }
 }
 
 impl<T, D, P> NextAttribute for Directive<T, D, P>