diff --git a/Cargo.lock b/Cargo.lock
index 732e62a9..b7555940 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1299,6 +1299,11 @@ name = "mdbook-core"
 version = "0.5.0-alpha.1"
 dependencies = [
  "anyhow",
+ "log",
+ "pulldown-cmark 0.10.3",
+ "regex",
+ "tempfile",
+ "toml",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index ee570234..a8c4331c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,7 +22,12 @@ rust-version = "1.85.0" # Keep in sync with installation.md and .github/workflow
 
 [workspace.dependencies]
 anyhow = "1.0.98"
+log = "0.4.27"
 mdbook-core = { path = "crates/mdbook-core" }
+pulldown-cmark = { version = "0.10.3", default-features = false, features = ["html"] } # Do not update, part of the public api.
+regex = "1.11.1"
+tempfile = "3.20.0"
+toml = "0.5.11" # Do not update, see https://github.com/rust-lang/mdBook/issues/2037
 
 [package]
 name = "mdbook"
@@ -50,18 +55,18 @@ clap_complete = "4.3.2"
 env_logger = "0.11.1"
 handlebars = "6.0"
 hex = "0.4.3"
-log = "0.4.17"
+log.workspace = true
 mdbook-core.workspace = true
 memchr = "2.5.0"
 opener = "0.8.1"
-pulldown-cmark = { version = "0.10.0", default-features = false, features = ["html"] } # Do not update, part of the public api.
-regex = "1.8.1"
+pulldown-cmark.workspace = true
+regex.workspace = true
 serde = { version = "1.0.163", features = ["derive"] }
 serde_json = "1.0.96"
 sha2 = "0.10.8"
 shlex = "1.3.0"
-tempfile = "3.4.0"
-toml = "0.5.11" # Do not update, see https://github.com/rust-lang/mdBook/issues/2037
+tempfile.workspace = true
+toml.workspace = true
 topological-sort = "0.2.2"
 
 # Watch feature
diff --git a/crates/mdbook-core/Cargo.toml b/crates/mdbook-core/Cargo.toml
index 301bfe87..a92a899a 100644
--- a/crates/mdbook-core/Cargo.toml
+++ b/crates/mdbook-core/Cargo.toml
@@ -9,6 +9,13 @@ rust-version.workspace = true
 
 [dependencies]
 anyhow.workspace = true
+log.workspace = true
+pulldown-cmark.workspace = true
+regex.workspace = true
+toml.workspace = true
+
+[dev-dependencies]
+tempfile.workspace = true
 
 [lints]
 workspace = true
diff --git a/crates/mdbook-core/src/lib.rs b/crates/mdbook-core/src/lib.rs
index d7298926..347d6668 100644
--- a/crates/mdbook-core/src/lib.rs
+++ b/crates/mdbook-core/src/lib.rs
@@ -10,3 +10,4 @@ pub const MDBOOK_VERSION: &str = env!("CARGO_PKG_VERSION");
 pub mod errors {
     pub use anyhow::{Error, Result};
 }
+pub mod utils;
diff --git a/crates/mdbook-core/src/utils/fs.rs b/crates/mdbook-core/src/utils/fs.rs
index 3d126b7a..c8500a73 100644
--- a/crates/mdbook-core/src/utils/fs.rs
+++ b/crates/mdbook-core/src/utils/fs.rs
@@ -29,7 +29,7 @@ pub fn write_file<P: AsRef<Path>>(build_dir: &Path, filename: P, content: &[u8])
 ///
 /// ```rust
 /// # use std::path::Path;
-/// # use mdbook::utils::fs::path_to_root;
+/// # use mdbook_core::utils::fs::path_to_root;
 /// let path = Path::new("some/relative/path");
 /// assert_eq!(path_to_root(path), "../../");
 /// ```
diff --git a/crates/mdbook-core/src/utils/mod.rs b/crates/mdbook-core/src/utils/mod.rs
index 50feb025..56bfbb97 100644
--- a/crates/mdbook-core/src/utils/mod.rs
+++ b/crates/mdbook-core/src/utils/mod.rs
@@ -12,7 +12,7 @@ use std::sync::LazyLock;
 
 pub mod fs;
 mod string;
-pub(crate) mod toml_ext;
+pub mod toml_ext;
 
 pub use self::string::{
     take_anchored_lines, take_lines, take_rustdoc_include_anchored_lines,
@@ -424,7 +424,8 @@ pub fn log_backtrace(e: &Error) {
     }
 }
 
-pub(crate) fn special_escape(mut s: &str) -> String {
+/// Escape characters to make it safe for an HTML string.
+pub fn special_escape(mut s: &str) -> String {
     let mut escaped = String::with_capacity(s.len());
     let needs_escape: &[char] = &['<', '>', '\'', '"', '\\', '&'];
     while let Some(next) = s.find(needs_escape) {
@@ -444,7 +445,8 @@ pub(crate) fn special_escape(mut s: &str) -> String {
     escaped
 }
 
-pub(crate) fn bracket_escape(mut s: &str) -> String {
+/// Escape `<` and `>` for HTML.
+pub fn bracket_escape(mut s: &str) -> String {
     let mut escaped = String::with_capacity(s.len());
     let needs_escape: &[char] = &['<', '>'];
     while let Some(next) = s.find(needs_escape) {
diff --git a/crates/mdbook-core/src/utils/toml_ext.rs b/crates/mdbook-core/src/utils/toml_ext.rs
index bf25ad11..7975ed57 100644
--- a/crates/mdbook-core/src/utils/toml_ext.rs
+++ b/crates/mdbook-core/src/utils/toml_ext.rs
@@ -1,9 +1,16 @@
+//! Helper for working with toml types.
+
 use toml::value::{Table, Value};
 
-pub(crate) trait TomlExt {
+/// Helper for working with toml types.
+pub trait TomlExt {
+    /// Read a dotted key.
     fn read(&self, key: &str) -> Option<&Value>;
+    /// Read a dotted key for a mutable value.
     fn read_mut(&mut self, key: &str) -> Option<&mut Value>;
+    /// Insert with a dotted key.
     fn insert(&mut self, key: &str, value: Value);
+    /// Delete a dotted key value.
     fn delete(&mut self, key: &str) -> Option<Value>;
 }
 
diff --git a/src/book/book.rs b/src/book/book.rs
index 769c503d..4e902664 100644
--- a/src/book/book.rs
+++ b/src/book/book.rs
@@ -6,9 +6,9 @@ use std::path::{Path, PathBuf};
 
 use super::summary::{Link, SectionNumber, Summary, SummaryItem, parse_summary};
 use crate::config::BuildConfig;
-use crate::utils::bracket_escape;
 use anyhow::{Context, Result};
 use log::debug;
+use mdbook_core::utils::bracket_escape;
 use serde::{Deserialize, Serialize};
 
 /// Load a book into memory from its `src/` directory.
diff --git a/src/book/init.rs b/src/book/init.rs
index b7372e33..07e8a43b 100644
--- a/src/book/init.rs
+++ b/src/book/init.rs
@@ -5,9 +5,9 @@ use std::path::PathBuf;
 use super::MDBook;
 use crate::config::Config;
 use crate::theme;
-use crate::utils::fs::write_file;
 use anyhow::{Context, Result};
 use log::{debug, error, info, trace};
+use mdbook_core::utils::fs::write_file;
 
 /// A helper for setting up a new book and its directory structure.
 #[derive(Debug, Clone, PartialEq)]
diff --git a/src/book/mod.rs b/src/book/mod.rs
index 117d6ed6..6d9cc670 100644
--- a/src/book/mod.rs
+++ b/src/book/mod.rs
@@ -27,7 +27,7 @@ use crate::preprocess::{
     CmdPreprocessor, IndexPreprocessor, LinkPreprocessor, Preprocessor, PreprocessorContext,
 };
 use crate::renderer::{CmdRenderer, HtmlHandlebars, MarkdownRenderer, RenderContext, Renderer};
-use crate::utils;
+use mdbook_core::utils;
 
 use crate::config::{Config, RustEdition};
 
diff --git a/src/cmd/serve.rs b/src/cmd/serve.rs
index 85866260..1d3ab6b9 100644
--- a/src/cmd/serve.rs
+++ b/src/cmd/serve.rs
@@ -10,7 +10,7 @@ use clap::builder::NonEmptyStringValueParser;
 use futures_util::StreamExt;
 use futures_util::sink::SinkExt;
 use mdbook::MDBook;
-use mdbook::utils::fs::get_404_output_file;
+use mdbook_core::utils::fs::get_404_output_file;
 use std::net::{SocketAddr, ToSocketAddrs};
 use std::path::PathBuf;
 use tokio::sync::broadcast;
diff --git a/src/config.rs b/src/config.rs
index 394154ae..4f91ceae 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -50,6 +50,8 @@
 use crate::utils::{self, toml_ext::TomlExt};
 use anyhow::{Context, Error, Result, bail};
 use log::{debug, trace, warn};
+use mdbook_core::utils::log_backtrace;
+use mdbook_core::utils::toml_ext::TomlExt;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use std::collections::HashMap;
 use std::env;
@@ -182,7 +184,7 @@ impl Config {
             Ok(Some(config)) => Some(config),
             Ok(None) => None,
             Err(e) => {
-                utils::log_backtrace(&e);
+                log_backtrace(&e);
                 None
             }
         }
@@ -812,7 +814,7 @@ impl<'de, T> Updateable<'de> for T where T: Serialize + Deserialize<'de> {}
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::utils::fs::get_404_output_file;
+    use mdbook_core::utils::fs::get_404_output_file;
     use serde_json::json;
 
     const COMPLEX_CONFIG: &str = r#"
diff --git a/src/lib.rs b/src/lib.rs
index 7abd2e15..d0b1af8b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -86,7 +86,6 @@ pub mod preprocess;
 pub mod renderer;
 #[path = "front-end/mod.rs"]
 pub mod theme;
-pub mod utils;
 
 pub use crate::book::BookItem;
 pub use crate::book::MDBook;
diff --git a/src/main.rs b/src/main.rs
index 975b5a21..e4e8d55f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,7 +11,7 @@ use clap::{Arg, ArgMatches, Command};
 use clap_complete::Shell;
 use env_logger::Builder;
 use log::LevelFilter;
-use mdbook::utils;
+use mdbook_core::utils;
 use std::env;
 use std::ffi::OsStr;
 use std::io::Write;
diff --git a/src/preprocess/links.rs b/src/preprocess/links.rs
index d431ea20..02d7c4d7 100644
--- a/src/preprocess/links.rs
+++ b/src/preprocess/links.rs
@@ -1,8 +1,8 @@
-use crate::utils::{
+use anyhow::{Context, Result};
+use mdbook_core::utils::{
     take_anchored_lines, take_lines, take_rustdoc_include_anchored_lines,
     take_rustdoc_include_lines,
 };
-use anyhow::{Context, Result};
 use regex::{CaptureMatches, Captures, Regex};
 use std::fs;
 use std::ops::{Bound, Range, RangeBounds, RangeFrom, RangeFull, RangeTo};
diff --git a/src/renderer/html_handlebars/hbs_renderer.rs b/src/renderer/html_handlebars/hbs_renderer.rs
index 4bef3cb3..dd90de55 100644
--- a/src/renderer/html_handlebars/hbs_renderer.rs
+++ b/src/renderer/html_handlebars/hbs_renderer.rs
@@ -4,8 +4,8 @@ use crate::renderer::html_handlebars::StaticFiles;
 use crate::renderer::html_handlebars::helpers;
 use crate::renderer::{RenderContext, Renderer};
 use crate::theme::{self, Theme};
-use crate::utils;
-use crate::utils::fs::get_404_output_file;
+use mdbook_core::utils;
+use mdbook_core::utils::fs::get_404_output_file;
 
 use std::borrow::Cow;
 use std::collections::BTreeMap;
diff --git a/src/renderer/html_handlebars/helpers/navigation.rs b/src/renderer/html_handlebars/helpers/navigation.rs
index 12c69027..1fd43dcf 100644
--- a/src/renderer/html_handlebars/helpers/navigation.rs
+++ b/src/renderer/html_handlebars/helpers/navigation.rs
@@ -5,8 +5,8 @@ use handlebars::{
     Context, Handlebars, Helper, Output, RenderContext, RenderError, RenderErrorReason, Renderable,
 };
 
-use crate::utils;
 use log::{debug, trace};
+use mdbook_core::utils;
 use serde_json::json;
 
 type StringMap = BTreeMap<String, String>;
diff --git a/src/renderer/html_handlebars/helpers/resources.rs b/src/renderer/html_handlebars/helpers/resources.rs
index e8818f05..88adafed 100644
--- a/src/renderer/html_handlebars/helpers/resources.rs
+++ b/src/renderer/html_handlebars/helpers/resources.rs
@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 
-use crate::utils;
+use mdbook_core::utils;
 
 use handlebars::{
     Context, Handlebars, Helper, HelperDef, Output, RenderContext, RenderError, RenderErrorReason,
diff --git a/src/renderer/html_handlebars/helpers/toc.rs b/src/renderer/html_handlebars/helpers/toc.rs
index a3419ce8..9528a355 100644
--- a/src/renderer/html_handlebars/helpers/toc.rs
+++ b/src/renderer/html_handlebars/helpers/toc.rs
@@ -1,7 +1,7 @@
 use std::path::Path;
 use std::{cmp::Ordering, collections::BTreeMap};
 
-use crate::utils::special_escape;
+use mdbook_core::utils::special_escape;
 
 use handlebars::{
     Context, Handlebars, Helper, HelperDef, Output, RenderContext, RenderError, RenderErrorReason,
diff --git a/src/renderer/html_handlebars/search.rs b/src/renderer/html_handlebars/search.rs
index 3299257d..ba9cd274 100644
--- a/src/renderer/html_handlebars/search.rs
+++ b/src/renderer/html_handlebars/search.rs
@@ -6,6 +6,7 @@ use std::sync::LazyLock;
 use anyhow::{Context, Result, bail};
 use elasticlunr::{Index, IndexBuilder};
 use log::{debug, warn};
+use mdbook_core::utils;
 use pulldown_cmark::*;
 use serde::Serialize;
 
@@ -13,7 +14,6 @@ use crate::book::{Book, BookItem, Chapter};
 use crate::config::{Search, SearchChapterSettings};
 use crate::renderer::html_handlebars::StaticFiles;
 use crate::theme::searcher;
-use crate::utils;
 
 const MAX_WORD_LENGTH_TO_INDEX: usize = 80;
 
diff --git a/src/renderer/html_handlebars/static_files.rs b/src/renderer/html_handlebars/static_files.rs
index 1b6aa9f7..ffd07687 100644
--- a/src/renderer/html_handlebars/static_files.rs
+++ b/src/renderer/html_handlebars/static_files.rs
@@ -2,11 +2,11 @@
 
 use anyhow::{Context, Result};
 use log::{debug, warn};
+use mdbook_core::utils;
 
 use crate::config::HtmlConfig;
 use crate::renderer::html_handlebars::helpers::resources::ResourceHelper;
 use crate::theme::{self, Theme, playground_editor};
-use crate::utils;
 
 use std::borrow::Cow;
 use std::collections::HashMap;
@@ -227,7 +227,7 @@ impl StaticFiles {
     }
 
     pub fn write_files(self, destination: &Path) -> Result<ResourceHelper> {
-        use crate::utils::fs::write_file;
+        use mdbook_core::utils::fs::write_file;
         use regex::bytes::{Captures, Regex};
         // The `{{ resource "name" }}` directive in static resources look like
         // handlebars syntax, even if they technically aren't.
@@ -302,7 +302,7 @@ mod tests {
     use super::*;
     use crate::config::HtmlConfig;
     use crate::theme::Theme;
-    use crate::utils::fs::write_file;
+    use mdbook_core::utils::fs::write_file;
     use tempfile::TempDir;
 
     #[test]
diff --git a/src/renderer/markdown_renderer.rs b/src/renderer/markdown_renderer.rs
index ac80aaa2..638b21f0 100644
--- a/src/renderer/markdown_renderer.rs
+++ b/src/renderer/markdown_renderer.rs
@@ -1,8 +1,8 @@
 use crate::book::BookItem;
 use crate::renderer::{RenderContext, Renderer};
-use crate::utils;
 use anyhow::{Context, Result};
 use log::trace;
+use mdbook_core::utils;
 use std::fs;
 
 #[derive(Default)]
diff --git a/tests/testsuite/book_test.rs b/tests/testsuite/book_test.rs
index ed5ebe83..57b5f3f3 100644
--- a/tests/testsuite/book_test.rs
+++ b/tests/testsuite/book_test.rs
@@ -35,7 +35,7 @@ impl BookTest {
         let dir = Path::new("tests/testsuite").join(dir);
         assert!(dir.exists(), "{dir:?} should exist");
         let tmp = Self::new_tmp();
-        mdbook::utils::fs::copy_files_except_ext(
+        mdbook_core::utils::fs::copy_files_except_ext(
             &dir,
             &tmp,
             true,
diff --git a/tests/testsuite/build.rs b/tests/testsuite/build.rs
index 1737bdf9..98972c4b 100644
--- a/tests/testsuite/build.rs
+++ b/tests/testsuite/build.rs
@@ -24,8 +24,8 @@ fn basic_build() {
 fn failure_on_missing_file() {
     BookTest::from_dir("build/missing_file").run("build", |cmd| {
         cmd.expect_failure().expect_stderr(str![[r#"
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Chapter file not found, ./chapter_1.md
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: [NOT_FOUND]
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Chapter file not found, ./chapter_1.md
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: [NOT_FOUND]
 
 "#]]);
     });
@@ -48,8 +48,8 @@ fn no_reserved_filename() {
         cmd.expect_failure().expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 [TIMESTAMP] [INFO] (mdbook::book): Running the html backend
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: print.md is reserved for internal use
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: print.md is reserved for internal use
 
 "#]]);
     });
diff --git a/tests/testsuite/markdown.rs b/tests/testsuite/markdown.rs
index 72643369..3fc08425 100644
--- a/tests/testsuite/markdown.rs
+++ b/tests/testsuite/markdown.rs
@@ -22,10 +22,10 @@ fn footnotes() {
             cmd.expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 [TIMESTAMP] [INFO] (mdbook::book): Running the html backend
-[TIMESTAMP] [WARN] (mdbook::utils): footnote `multiple-definitions` in <unknown> defined multiple times - not updating to new definition
-[TIMESTAMP] [WARN] (mdbook::utils): footnote `unused` in `<unknown>` is defined but not referenced
-[TIMESTAMP] [WARN] (mdbook::utils): footnote `multiple-definitions` in footnotes.md defined multiple times - not updating to new definition
-[TIMESTAMP] [WARN] (mdbook::utils): footnote `unused` in `footnotes.md` is defined but not referenced
+[TIMESTAMP] [WARN] (mdbook_core::utils): footnote `multiple-definitions` in <unknown> defined multiple times - not updating to new definition
+[TIMESTAMP] [WARN] (mdbook_core::utils): footnote `unused` in `<unknown>` is defined but not referenced
+[TIMESTAMP] [WARN] (mdbook_core::utils): footnote `multiple-definitions` in footnotes.md defined multiple times - not updating to new definition
+[TIMESTAMP] [WARN] (mdbook_core::utils): footnote `unused` in `footnotes.md` is defined but not referenced
 [TIMESTAMP] [INFO] (mdbook::renderer::html_handlebars::hbs_renderer): HTML book written to `[ROOT]/book`
 
 "#]]);
diff --git a/tests/testsuite/preprocessor.rs b/tests/testsuite/preprocessor.rs
index b2188db1..51f4a2a2 100644
--- a/tests/testsuite/preprocessor.rs
+++ b/tests/testsuite/preprocessor.rs
@@ -64,7 +64,7 @@ fn failing_preprocessor() {
                 .expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 Boom!!1!
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: The "nop-preprocessor" preprocessor exited unsuccessfully with [EXIT_STATUS]: 1 status
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: The "nop-preprocessor" preprocessor exited unsuccessfully with [EXIT_STATUS]: 1 status
 
 "#]]);
         });
diff --git a/tests/testsuite/redirects.rs b/tests/testsuite/redirects.rs
index d92bf766..93fd9113 100644
--- a/tests/testsuite/redirects.rs
+++ b/tests/testsuite/redirects.rs
@@ -24,9 +24,9 @@ fn redirect_removed_with_fragments_only() {
         cmd.expect_failure().expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 [TIMESTAMP] [INFO] (mdbook::book): Running the html backend
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: Unable to emit redirects
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: redirect entry for `old-file.html` only has source paths with `#` fragments
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: Unable to emit redirects
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: redirect entry for `old-file.html` only has source paths with `#` fragments
 There must be an entry without the `#` fragment to determine the default destination.
 
 "#]]);
@@ -40,8 +40,8 @@ fn redirect_existing_page() {
         cmd.expect_failure().expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 [TIMESTAMP] [INFO] (mdbook::book): Running the html backend
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: redirect found for existing chapter at `/chapter_1.html`
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: redirect found for existing chapter at `/chapter_1.html`
 Either delete the redirect or remove the chapter.
 
 "#]]);
diff --git a/tests/testsuite/renderer.rs b/tests/testsuite/renderer.rs
index 45739d09..923bd5dd 100644
--- a/tests/testsuite/renderer.rs
+++ b/tests/testsuite/renderer.rs
@@ -68,8 +68,8 @@ fn failing_command() {
 [TIMESTAMP] [INFO] (mdbook::book): Running the failing backend
 [TIMESTAMP] [INFO] (mdbook::renderer): Invoking the "failing" renderer
 [TIMESTAMP] [ERROR] (mdbook::renderer): Renderer exited with non-zero return code.
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: The "failing" renderer failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: The "failing" renderer failed
 
 "#]]);
         });
@@ -86,9 +86,9 @@ fn missing_renderer() {
 [TIMESTAMP] [INFO] (mdbook::book): Running the missing backend
 [TIMESTAMP] [INFO] (mdbook::renderer): Invoking the "missing" renderer
 [TIMESTAMP] [ERROR] (mdbook::renderer): The command `trduyvbhijnorgevfuhn` wasn't found, is the "missing" backend installed? If you want to ignore this error when the "missing" backend is not installed, set `optional = true` in the `[output.missing]` section of the book.toml configuration file.
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: Unable to start the backend
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: [NOT_FOUND]
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: Unable to start the backend
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: [NOT_FOUND]
 
 "#]]);
     });
diff --git a/tests/testsuite/search.rs b/tests/testsuite/search.rs
index 5eca0e43..a8f05120 100644
--- a/tests/testsuite/search.rs
+++ b/tests/testsuite/search.rs
@@ -137,8 +137,8 @@ fn chapter_settings_validation_error() {
         cmd.expect_failure().expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 [TIMESTAMP] [INFO] (mdbook::book): Running the html backend
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: [output.html.search.chapter] key `does-not-exist` does not match any chapter paths
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: [output.html.search.chapter] key `does-not-exist` does not match any chapter paths
 
 "#]]);
     });
diff --git a/tests/testsuite/test.rs b/tests/testsuite/test.rs
index 54be8695..5fd2cc7e 100644
--- a/tests/testsuite/test.rs
+++ b/tests/testsuite/test.rs
@@ -48,7 +48,7 @@ test failing_include.md - Failing_Include (line 3) ... FAILED
 thread 'main' panicked at failing_include.md:3:1:
 failing!
 ...
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: One or more tests failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: One or more tests failed
 
 "#]]);
     });
@@ -82,7 +82,7 @@ fn chapter_not_found() {
         cmd.expect_failure()
             .expect_stdout(str![[""]])
             .expect_stderr(str![[r#"
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Chapter not found: bogus
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Chapter not found: bogus
 
 "#]]);
     });
diff --git a/tests/testsuite/theme.rs b/tests/testsuite/theme.rs
index b22ae4e2..8ebb0c64 100644
--- a/tests/testsuite/theme.rs
+++ b/tests/testsuite/theme.rs
@@ -11,8 +11,8 @@ cmd.expect_failure()
         .expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook::book): Book building has started
 [TIMESTAMP] [INFO] (mdbook::book): Running the html backend
-[TIMESTAMP] [ERROR] (mdbook::utils): Error: Rendering failed
-[TIMESTAMP] [ERROR] (mdbook::utils): [TAB]Caused By: theme dir [ROOT]/./non-existent-directory does not exist
+[TIMESTAMP] [ERROR] (mdbook_core::utils): Error: Rendering failed
+[TIMESTAMP] [ERROR] (mdbook_core::utils): [TAB]Caused By: theme dir [ROOT]/./non-existent-directory does not exist
 
 "#]]);
     });