From c1985d64a1d2bdf01d6498a0f11a368911782c4b Mon Sep 17 00:00:00 2001
From: Ofek <ofekshilon@gmail.com>
Date: Fri, 25 Oct 2024 12:19:04 +0300
Subject: [PATCH] Tsification binge #7 (#6974)

---
 lib/base-compiler.ts                        | 13 ++--
 lib/buildenvsetup/ceconan.ts                |  5 +-
 lib/cfg/cfg-parsers/base.ts                 |  5 +-
 lib/cfg/cfg-parsers/oat.ts                  |  3 +-
 lib/compilers/cerberus.ts                   |  5 +-
 lib/compilers/d8.ts                         |  4 +-
 lib/compilers/hook.ts                       | 10 +--
 lib/compilers/java.ts                       |  4 +-
 lib/llvm-ir.ts                              |  4 +-
 lib/options-handler.ts                      |  5 +-
 lib/parsers/asm-parser-cpp.ts               |  5 +-
 lib/parsers/asm-parser-spirv.ts             |  3 +-
 lib/parsers/asm-parser.interfaces.ts        |  3 +-
 package-lock.json                           |  8 +++
 package.json                                |  1 +
 static/ansi-to-html.ts                      |  2 +-
 static/assert.ts                            |  2 +-
 static/compiler-service.ts                  |  6 +-
 static/compiler-shared.interfaces.ts        |  2 +-
 static/components.ts                        |  4 +-
 static/download-service.ts                  |  4 +-
 static/event-map.ts                         |  4 +-
 static/graph-layout-core.ts                 | 10 +--
 static/hub.ts                               | 80 ++++++++++++---------
 static/lib-utils.ts                         |  3 +-
 static/line-colouring.ts                    |  3 +-
 static/local.ts                             |  2 +-
 static/modes/carbon-mode.ts                 |  2 +
 static/modes/cpp-for-opencl-mode.ts         |  2 +
 static/modes/cppcircle-mode.ts              |  2 +
 static/modes/cppfront-mode.ts               | 15 +++-
 static/modes/cppp-mode.ts                   |  2 +
 static/modes/cppx-blue-mode.ts              |  2 +
 static/modes/cuda-mode.ts                   |  2 +
 static/modes/glsl-mode.ts                   |  2 +
 static/modes/hlsl-mode.ts                   |  2 +
 static/modes/hylo-mode.ts                   |  2 +
 static/modes/ispc-mode.ts                   |  2 +
 static/modes/nc-mode.ts                     |  2 +
 static/modes/openclc-mode.ts                |  2 +
 static/multifile-service.ts                 |  2 +-
 static/options.interfaces.ts                |  2 +-
 static/options.ts                           |  2 +-
 static/panes/ast-view.ts                    |  5 +-
 static/panes/cfg-view.ts                    |  2 +-
 static/panes/clangir-view.ts                |  5 +-
 static/panes/compiler.ts                    |  9 ++-
 static/panes/device-view.ts                 |  2 +-
 static/panes/diff.ts                        |  6 +-
 static/panes/editor.interfaces.ts           |  4 +-
 static/panes/editor.ts                      | 12 ++--
 static/panes/executor.ts                    |  4 +-
 static/panes/flags-view.ts                  |  2 +-
 static/panes/gccdump-view.ts                | 32 +++++----
 static/panes/gnatdebug-view.ts              |  5 +-
 static/panes/gnatdebugtree-view.ts          |  5 +-
 static/panes/haskellcmm-view.ts             |  5 +-
 static/panes/haskellcore-view.ts            |  5 +-
 static/panes/haskellstg-view.ts             |  5 +-
 static/panes/ir-view.ts                     |  3 +-
 static/panes/opt-pipeline.ts                |  5 +-
 static/panes/output.ts                      | 12 ++--
 static/panes/pp-view.ts                     |  8 +--
 static/panes/rusthir-view.ts                |  5 +-
 static/panes/rustmacroexp-view.ts           |  5 +-
 static/panes/rustmir-view.ts                |  5 +-
 static/panes/stack-usage-view.ts            |  2 +-
 static/panes/tool-input-view.ts             | 21 +++---
 static/panes/tool.ts                        |  4 +-
 static/panes/tree.ts                        |  7 +-
 static/print-view.ts                        |  2 +-
 static/rison.ts                             |  6 +-
 static/sentry.ts                            |  3 +-
 static/settings.ts                          |  4 +-
 static/sharing.ts                           | 13 ++--
 static/tests/frontend-testing.interfaces.ts |  2 +-
 static/tests/motd.ts                        |  7 +-
 static/utils.ts                             |  6 +-
 static/widgets/alert.interfaces.ts          |  2 +-
 static/widgets/compiler-picker.ts           | 12 ++--
 static/widgets/load-save.ts                 |  2 +-
 static/widgets/toggles.ts                   |  6 +-
 test/compilers/hook-tests.ts                |  6 +-
 test/java-tests.ts                          |  4 +-
 types/compilation/cfg.interfaces.ts         |  4 +-
 types/compilation/compilation.interfaces.ts | 12 ++--
 types/compiler.interfaces.ts                | 12 ++--
 87 files changed, 331 insertions(+), 202 deletions(-)

diff --git a/lib/base-compiler.ts b/lib/base-compiler.ts
index 93cf05ed8..90a971f04 100644
--- a/lib/base-compiler.ts
+++ b/lib/base-compiler.ts
@@ -2342,7 +2342,7 @@ export class BaseCompiler implements ICompiler {
                   !!this.compiler.removeEmptyGccDump,
                   outputFilename,
               )
-            : '';
+            : null;
         const rustMirResult = makeRustMir ? await this.processRustMirOutput(outputFilename, asmResult) : undefined;
 
         const haskellCoreResult = makeHaskellCore
@@ -3078,7 +3078,12 @@ export class BaseCompiler implements ICompiler {
         );
     }
 
-    async processGccDumpOutput(opts: GccDumpOptions, result, removeEmptyPasses: boolean, outputFilename: string) {
+    async processGccDumpOutput(
+        opts: GccDumpOptions,
+        result,
+        removeEmptyPasses: boolean | undefined,
+        outputFilename: string,
+    ) {
         const rootDir = path.dirname(result.inputFilename);
 
         if (opts.treeDump === false && opts.rtlDump === false && opts.ipaDump === false) {
@@ -3092,7 +3097,7 @@ export class BaseCompiler implements ICompiler {
 
         const output = {
             all: [] as any[],
-            selectedPass: opts.pass,
+            selectedPass: opts.pass ?? null,
             currentPassOutput: '<No pass selected>',
             syntaxHighlight: false,
         };
@@ -3194,7 +3199,7 @@ but nothing was dumped. Possible causes are:
         return result;
     }
 
-    async execPostProcess(result, postProcesses, outputFilename: string, maxSize: number) {
+    async execPostProcess(result, postProcesses: string[], outputFilename: string, maxSize: number) {
         const postCommand = `cat "${outputFilename}" | ${postProcesses.join(' | ')}`;
         return this.handlePostProcessResult(result, await this.exec('bash', ['-c', postCommand], {maxOutput: maxSize}));
     }
diff --git a/lib/buildenvsetup/ceconan.ts b/lib/buildenvsetup/ceconan.ts
index 74682f6a4..e76570e7c 100644
--- a/lib/buildenvsetup/ceconan.ts
+++ b/lib/buildenvsetup/ceconan.ts
@@ -32,6 +32,7 @@ import _ from 'underscore';
 
 import {CacheKey} from '../../types/compilation/compilation.interfaces.js';
 import {CompilerInfo} from '../../types/compiler.interfaces.js';
+import {CompilationEnvironment} from '../compilation-env.js';
 import {logger} from '../logger.js';
 import {VersionInfo} from '../options-handler.js';
 
@@ -67,14 +68,12 @@ export class BuildEnvSetupCeConanDirect extends BuildEnvSetupBase {
         return 'ceconan';
     }
 
-    constructor(compilerInfo: CompilerInfo, env) {
+    constructor(compilerInfo: CompilerInfo, env: CompilationEnvironment) {
         super(compilerInfo, env);
 
         this.host = compilerInfo.buildenvsetup!.props('host', '');
         this.onlyonstaticliblink = compilerInfo.buildenvsetup!.props('onlyonstaticliblink', '');
         this.extractAllToRoot = false;
-
-        if (env.debug) request.debug = true;
     }
 
     async getAllPossibleBuilds(libid: string, version: string) {
diff --git a/lib/cfg/cfg-parsers/base.ts b/lib/cfg/cfg-parsers/base.ts
index 6a2fba4d4..dcaba3803 100644
--- a/lib/cfg/cfg-parsers/base.ts
+++ b/lib/cfg/cfg-parsers/base.ts
@@ -24,6 +24,7 @@
 
 import _ from 'underscore';
 
+import {EdgeColor} from '../../../types/compilation/cfg.interfaces.js';
 import type {ResultLineSource} from '../../../types/resultline/resultline.interfaces.js';
 import {logger} from '../../logger.js';
 import {BaseInstructionSetInfo, InstructionType} from '../instruction-sets/base.js';
@@ -55,7 +56,7 @@ export type Edge = {
     from: string;
     to: string;
     arrows: string;
-    color: string;
+    color: EdgeColor;
 };
 
 export type AssemblyLine = {
@@ -237,7 +238,7 @@ export class BaseCFGParser {
     protected makeEdges(asmArr: AssemblyLine[], arrOfCanonicalBasicBlock: CanonicalBB[]) {
         const edges: Edge[] = [];
 
-        const setEdge = (sourceNode: string, targetNode: string, color: string) => ({
+        const setEdge = (sourceNode: string, targetNode: string, color: EdgeColor) => ({
             from: sourceNode,
             to: targetNode,
             arrows: 'to',
diff --git a/lib/cfg/cfg-parsers/oat.ts b/lib/cfg/cfg-parsers/oat.ts
index 7c3563007..3bb6485ee 100644
--- a/lib/cfg/cfg-parsers/oat.ts
+++ b/lib/cfg/cfg-parsers/oat.ts
@@ -24,6 +24,7 @@
 
 import _ from 'underscore';
 
+import {EdgeColor} from '../../../types/compilation/cfg.interfaces.js';
 import {logger} from '../../logger.js';
 import {BaseInstructionSetInfo, InstructionType} from '../instruction-sets/base.js';
 
@@ -249,7 +250,7 @@ export class OatCFGParser extends BaseCFGParser {
     override makeEdges(asmArr: AssemblyLine[], arrOfCanonicalBasicBlock: CanonicalBB[]) {
         const edges: Edge[] = [];
 
-        const setEdge = (sourceNode: string, targetNode: string, color: string) => ({
+        const setEdge = (sourceNode: string, targetNode: string, color: EdgeColor) => ({
             from: sourceNode,
             to: targetNode,
             arrows: 'to',
diff --git a/lib/compilers/cerberus.ts b/lib/compilers/cerberus.ts
index b73641e5d..6d9a51213 100644
--- a/lib/compilers/cerberus.ts
+++ b/lib/compilers/cerberus.ts
@@ -24,6 +24,7 @@
 
 import path from 'path';
 
+import {ParsedAsmResult} from '../../types/asmresult/asmresult.interfaces.js';
 import {BypassCache, CacheKey, ExecutionOptions} from '../../types/compilation/compilation.interfaces.js';
 import type {PreliminaryCompilerInfo} from '../../types/compiler.interfaces.js';
 import {ExecutableExecutionOptions} from '../../types/execution/execution.interfaces.js';
@@ -114,10 +115,10 @@ export class CerberusCompiler extends BaseCompiler {
         }
     }
 
-    override async processAsm(result) {
+    override async processAsm(result): Promise<ParsedAsmResult> {
         // Handle "error" documents.
         if (!result.asm.includes('\n') && result.asm[0] === '<') {
-            return [{text: result.asm, source: null}];
+            return {asm: [{text: result.asm, source: null}]};
         }
 
         const lines = result.asm.split('\n');
diff --git a/lib/compilers/d8.ts b/lib/compilers/d8.ts
index 4002f491f..69403abf9 100644
--- a/lib/compilers/d8.ts
+++ b/lib/compilers/d8.ts
@@ -220,9 +220,9 @@ export class D8Compiler extends BaseCompiler implements SimpleOutputFilenameComp
     }
 
     // Map line numbers to lines.
-    override async processAsm(result) {
+    override async processAsm(result): Promise<ParsedAsmResult> {
         if (result.code !== 0) {
-            return [{text: result.asm, source: null}];
+            return {asm: [{text: result.asm, source: null}]};
         }
         const segments: ParsedAsmResultLine[] = [];
         const asm = result.asm[0].text;
diff --git a/lib/compilers/hook.ts b/lib/compilers/hook.ts
index 7ee14e128..4630e0766 100644
--- a/lib/compilers/hook.ts
+++ b/lib/compilers/hook.ts
@@ -86,12 +86,12 @@ export class HookCompiler extends BaseCompiler {
         const commentRegex = /^\s*;(.*)/;
         const instructionRegex = /^\s{2}(\d+)(.*)/;
         const asm = _result.asm;
-        let lastLineNo: number | undefined;
+        let lastLineNo: number | null = null;
         for (const item of asm) {
             const text = item.text;
             if (commentRegex.test(text)) {
-                item.source = {line: undefined, file: null};
-                lastLineNo = undefined;
+                item.source = {line: null, file: null};
+                lastLineNo = null;
                 continue;
             }
             const match = text.match(instructionRegex);
@@ -105,8 +105,8 @@ export class HookCompiler extends BaseCompiler {
                 item.source = {line: lastLineNo, file: null};
                 continue;
             }
-            item.source = {line: undefined, file: null};
-            lastLineNo = undefined;
+            item.source = {line: null, file: null};
+            lastLineNo = null;
         }
         _result.asm = asm;
         return _result;
diff --git a/lib/compilers/java.ts b/lib/compilers/java.ts
index 9f590c456..92186a93b 100644
--- a/lib/compilers/java.ts
+++ b/lib/compilers/java.ts
@@ -248,10 +248,10 @@ export class JavaCompiler extends BaseCompiler implements SimpleOutputFilenameCo
         return this.filterUserOptionsWithArg(userOptions, oneArgForbiddenList);
     }
 
-    override async processAsm(result) {
+    override async processAsm(result): Promise<ParsedAsmResult> {
         // Handle "error" documents.
         if (!result.asm.includes('\n') && result.asm[0] === '<') {
-            return [{text: result.asm, source: null}];
+            return {asm: [{text: result.asm, source: null}]};
         }
 
         // result.asm is an array of javap stdouts
diff --git a/lib/llvm-ir.ts b/lib/llvm-ir.ts
index 499c4ecba..6c4e7ee3b 100644
--- a/lib/llvm-ir.ts
+++ b/lib/llvm-ir.ts
@@ -23,7 +23,7 @@
 // POSSIBILITY OF SUCH DAMAGE.
 
 import {isString} from '../shared/common-utils.js';
-import type {IRResultLine} from '../types/asmresult/asmresult.interfaces.js';
+import type {IRResultLine, ParsedAsmResult} from '../types/asmresult/asmresult.interfaces.js';
 import {LLVMIrBackendOptions} from '../types/compilation/ir.interfaces.js';
 import {ParseFiltersAndOutputOptions} from '../types/features/filters.interfaces.js';
 
@@ -264,7 +264,7 @@ export class LlvmIrParser {
         }
     }
 
-    async processFromFilters(ir: string, filters: ParseFiltersAndOutputOptions) {
+    async processFromFilters(ir: string, filters: ParseFiltersAndOutputOptions): Promise<ParsedAsmResult> {
         if (isString(ir)) {
             return await this.processIr(ir, {
                 filterDebugInfo: !!filters.debugCalls,
diff --git a/lib/options-handler.ts b/lib/options-handler.ts
index 03705fb8b..3a9fcc7aa 100755
--- a/lib/options-handler.ts
+++ b/lib/options-handler.ts
@@ -56,6 +56,7 @@ export type VersionInfo = {
     options: string[];
     hidden: boolean;
     packagedheaders?: boolean;
+    $order?: number;
 };
 export type OptionsHandlerLibrary = {
     name: string;
@@ -439,7 +440,7 @@ export class ClientOptionsHandler {
             'isSemVer',
         ]);
         const copiedCompilers = JSON.parse(JSON.stringify(compilers)) as CompilerInfo[];
-        const semverGroups: Record<string, any> = {};
+        const semverGroups: Record<string, Partial<CompilerInfo>[]> = {};
         // Reset the supportsExecute flag in case critical compilers change
 
         for (const key of Object.keys(this.options.languages)) {
@@ -462,7 +463,7 @@ export class ClientOptionsHandler {
 
             for (const propKey of Object.keys(compiler)) {
                 if (forbiddenKeys.has(propKey)) {
-                    delete copiedCompilers[compilersKey][propKey];
+                    delete copiedCompilers[compilersKey][propKey as keyof CompilerInfo];
                 }
             }
         }
diff --git a/lib/parsers/asm-parser-cpp.ts b/lib/parsers/asm-parser-cpp.ts
index 75c2d346f..bd173d15a 100644
--- a/lib/parsers/asm-parser-cpp.ts
+++ b/lib/parsers/asm-parser-cpp.ts
@@ -22,6 +22,7 @@
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 
+import {ParsedAsmResult} from '../../types/asmresult/asmresult.interfaces.js';
 import {ParseFiltersAndOutputOptions} from '../../types/features/filters.interfaces.js';
 import * as utils from '../utils.js';
 
@@ -33,7 +34,7 @@ type Source = {file: string | null; line: number};
 const lineRe = /^\s*#line\s+(?<line>\d+)\s+"(?<file>[^"]+)"/;
 
 export class AsmParserCpp implements IAsmParser {
-    process(asmResult: string, filters: ParseFiltersAndOutputOptions) {
+    process(asmResult: string, filters: ParseFiltersAndOutputOptions): ParsedAsmResult {
         const startTime = process.hrtime.bigint();
 
         const asm: {
@@ -69,7 +70,7 @@ export class AsmParserCpp implements IAsmParser {
         const endTime = process.hrtime.bigint();
         return {
             asm: asm,
-            labelDefinitions: [],
+            labelDefinitions: {},
             parsingTime: ((endTime - startTime) / BigInt(1000000)).toString(),
             filteredCount: 0,
         };
diff --git a/lib/parsers/asm-parser-spirv.ts b/lib/parsers/asm-parser-spirv.ts
index d4798dec5..209edf5ea 100644
--- a/lib/parsers/asm-parser-spirv.ts
+++ b/lib/parsers/asm-parser-spirv.ts
@@ -23,6 +23,7 @@
 // POSSIBILITY OF SUCH DAMAGE.
 
 import {AsmResultLabel, ParsedAsmResultLine} from '../../types/asmresult/asmresult.interfaces.js';
+import {ParseFiltersAndOutputOptions} from '../../types/features/filters.interfaces.js';
 import * as utils from '../utils.js';
 
 import {AsmParser} from './asm-parser.js';
@@ -84,7 +85,7 @@ export class SPIRVAsmParser extends AsmParser {
         return labelsInLine;
     }
 
-    override processAsm(asmResult, filters) {
+    override processAsm(asmResult, filters: ParseFiltersAndOutputOptions) {
         const startTime = process.hrtime.bigint();
 
         const asm: ParsedAsmResultLine[] = [];
diff --git a/lib/parsers/asm-parser.interfaces.ts b/lib/parsers/asm-parser.interfaces.ts
index 4957a32e1..0b9885894 100644
--- a/lib/parsers/asm-parser.interfaces.ts
+++ b/lib/parsers/asm-parser.interfaces.ts
@@ -1,5 +1,6 @@
+import {ParsedAsmResult} from '../../types/asmresult/asmresult.interfaces.js';
 import {ParseFiltersAndOutputOptions} from '../../types/features/filters.interfaces.js';
 
 export interface IAsmParser {
-    process(asm: string, filters: ParseFiltersAndOutputOptions);
+    process(asm: string, filters: ParseFiltersAndOutputOptions): ParsedAsmResult;
 }
diff --git a/package-lock.json b/package-lock.json
index e0892b397..0df1e4c47 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -81,6 +81,7 @@
         "@smithy/util-stream": "^3.1.9",
         "@types/body-parser": "^1.19.5",
         "@types/bootstrap": "^5.2.10",
+        "@types/chai": "^5.0.0",
         "@types/compression": "^1.7.5",
         "@types/express": "^4.17.21",
         "@types/file-saver": "^2.0.7",
@@ -4100,6 +4101,13 @@
       "integrity": "sha512-hWtVTC2q7hc7xZ/RLbxapMvDMgUnDvKvMOpKal4DrMyfGBUfB1oKaZlIRr6mJL+If3bAP6sV/QneGzF6tJjZDg==",
       "dev": true
     },
+    "node_modules/@types/chai": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/@types/chai/-/chai-5.0.0.tgz",
+      "integrity": "sha512-+DwhEHAaFPPdJ2ral3kNHFQXnTfscEEFsUxzD+d7nlcLrFK23JtNjH71RGasTcHb88b4vVi4mTyfpf8u2L8bdA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/compression": {
       "version": "1.7.5",
       "resolved": "https://registry.npmjs.org/@types/compression/-/compression-1.7.5.tgz",
diff --git a/package.json b/package.json
index 26666b462..2c3276b35 100644
--- a/package.json
+++ b/package.json
@@ -90,6 +90,7 @@
     "@smithy/util-stream": "^3.1.9",
     "@types/body-parser": "^1.19.5",
     "@types/bootstrap": "^5.2.10",
+    "@types/chai": "^5.0.0",
     "@types/compression": "^1.7.5",
     "@types/express": "^4.17.21",
     "@types/file-saver": "^2.0.7",
diff --git a/static/ansi-to-html.ts b/static/ansi-to-html.ts
index 760e37253..dfad84cbc 100644
--- a/static/ansi-to-html.ts
+++ b/static/ansi-to-html.ts
@@ -323,7 +323,7 @@ function tokenize(text: string, options: AnsiToHtmlOptions, callback: TokenizeCa
         return '';
     }
 
-    function rgb(m) {
+    function rgb(m: string) {
         callback('rgb', m);
         return '';
     }
diff --git a/static/assert.ts b/static/assert.ts
index 82a2ff50a..d41465213 100644
--- a/static/assert.ts
+++ b/static/assert.ts
@@ -67,7 +67,7 @@ function fail(fail_message: string, user_message: string | undefined, args: any[
     }
 }
 
-export function assert<C>(c: C, message?: string, ...extra_info: any[]): asserts c {
+export function assert(c: unknown, message?: string, ...extra_info: any[]): asserts c {
     if (!c) {
         fail('Assertion failed', message, extra_info);
     }
diff --git a/static/compiler-service.ts b/static/compiler-service.ts
index 2d12e20fc..8afb470e8 100644
--- a/static/compiler-service.ts
+++ b/static/compiler-service.ts
@@ -38,6 +38,7 @@ import {CompilationResult, FiledataPair} from '../types/compilation/compilation.
 import {CompilationStatus} from './compiler-service.interfaces.js';
 import {IncludeDownloads, SourceAndFiles} from './download-service.js';
 import {SentryCapture} from './sentry.js';
+import {SiteSettings} from './settings.js';
 
 const ASCII_COLORS_RE = new RegExp(/\x1B\[[\d;]*m(.\[K)?/g);
 
@@ -61,7 +62,10 @@ export class CompilerService {
             this.compilersByLang[compiler.lang][compiler.id] = compiler;
         }
 
-        eventHub.on('settingsChange', newSettings => (this.allowStoreCodeDebug = newSettings.allowStoreCodeDebug));
+        eventHub.on(
+            'settingsChange',
+            (newSettings: SiteSettings) => (this.allowStoreCodeDebug = newSettings.allowStoreCodeDebug),
+        );
     }
 
     private getDefaultCompilerForLang(langId: string) {
diff --git a/static/compiler-shared.interfaces.ts b/static/compiler-shared.interfaces.ts
index fbe4306fc..70e103182 100644
--- a/static/compiler-shared.interfaces.ts
+++ b/static/compiler-shared.interfaces.ts
@@ -28,7 +28,7 @@ import type {CompilerState} from './panes/compiler.interfaces.js';
 import type {ExecutorState} from './panes/executor.interfaces.js';
 
 export interface ICompilerShared {
-    updateState(state: CompilerState | ExecutorState);
+    updateState(state: CompilerState | ExecutorState): void;
     getOverrides(): ConfiguredOverrides | undefined;
     getRuntimeTools(): ConfiguredRuntimeTools | undefined;
 }
diff --git a/static/components.ts b/static/components.ts
index 0227ca942..827ab223d 100644
--- a/static/components.ts
+++ b/static/components.ts
@@ -186,8 +186,8 @@ export function getExecutorWith(
     editorId: number,
     lang: string,
     compilerId: string,
-    libraries: unknown,
-    compilerArgs,
+    libraries: {name: string; ver: string}[],
+    compilerArgs: string | undefined,
     treeId: number,
     overrides?: ConfiguredOverrides,
     runtimeTools?: ConfiguredRuntimeTools,
diff --git a/static/download-service.ts b/static/download-service.ts
index 913dd7589..376548e35 100644
--- a/static/download-service.ts
+++ b/static/download-service.ts
@@ -40,7 +40,7 @@ export class IncludeDownloads {
     private toDownload: FileToDownload[] = [];
     private downloadPromises: Promise<FileToDownload>[] = [];
 
-    private async doDownload(download): Promise<FileToDownload> {
+    private async doDownload(download: FileToDownload): Promise<FileToDownload> {
         try {
             const response = await fetch(download.url);
             if (response.status >= 400) {
@@ -55,7 +55,7 @@ export class IncludeDownloads {
         return download;
     }
 
-    private async startDownload(download) {
+    private async startDownload(download: FileToDownload) {
         this.downloadPromises.push(this.doDownload(download));
     }
 
diff --git a/static/event-map.ts b/static/event-map.ts
index 841818d99..c42bc4562 100644
--- a/static/event-map.ts
+++ b/static/event-map.ts
@@ -156,10 +156,10 @@ export type EventMap = {
     // TODO: There are no emitters for this event
     selectLine: (editorId: number, lineNumber: number) => void;
     settingsChange: (newSettings: SiteSettings) => void;
-    setToolInput: (compilerId: number, toolId: string, string: string) => void;
+    setToolInput: (compilerId: number, toolId: string, value: string) => void;
     shown: () => void;
     themeChange: (newTheme: Theme | null) => void;
-    toolClosed: (compilerId: number, toolState: unknown) => void;
+    toolClosed: (compilerId: number, toolState: ToolState) => void;
     toolInputChange: (compilerId: number, toolId: string, input: string) => void;
     toolInputViewClosed: (compilerId: number, toolId: string, input: string) => void;
     toolInputViewCloseRequest: (compilerId: number, toolId: string) => void;
diff --git a/static/graph-layout-core.ts b/static/graph-layout-core.ts
index cb5875120..3709a0b74 100644
--- a/static/graph-layout-core.ts
+++ b/static/graph-layout-core.ts
@@ -22,7 +22,7 @@
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 
-import {AnnotatedCfgDescriptor, AnnotatedNodeDescriptor} from '../types/compilation/cfg.interfaces.js';
+import {AnnotatedCfgDescriptor, AnnotatedNodeDescriptor, EdgeColor} from '../types/compilation/cfg.interfaces.js';
 
 import IntervalTree from '@flatten-js/interval-tree';
 
@@ -70,7 +70,7 @@ type EdgeSegment = {
 };
 
 type Edge = {
-    color: string;
+    color: EdgeColor;
     dest: number;
     mainColumn: number;
     path: EdgeSegment[];
@@ -214,7 +214,7 @@ export class GraphLayoutCore {
         return order.reverse();
     }
 
-    assignRows(topologicalOrder) {
+    assignRows(topologicalOrder: number[]) {
         for (const i of topologicalOrder) {
             const block = this.blocks[i];
             //console.log(block);
@@ -225,7 +225,7 @@ export class GraphLayoutCore {
         }
     }
 
-    computeTree(topologicalOrder) {
+    computeTree(topologicalOrder: number[]) {
         // DAG is reduced to a tree based on what's vertically adjacent
         //
         // For something like
@@ -317,7 +317,7 @@ export class GraphLayoutCore {
         }
     }
 
-    assignColumns(topologicalOrder) {
+    assignColumns(topologicalOrder: number[]) {
         // Note: Currently not taking shape into account like Cutter does.
         // Post DFS order means we compute all children before their parents
         for (const i of topologicalOrder.slice().reverse()) {
diff --git a/static/hub.ts b/static/hub.ts
index 621ec783a..5f200acef 100644
--- a/static/hub.ts
+++ b/static/hub.ts
@@ -23,6 +23,7 @@
 // POSSIBILITY OF SUCH DAMAGE.
 
 import GoldenLayout, {ContentItem} from 'golden-layout';
+type GLC = GoldenLayout.Container;
 
 import {CompilerService} from './compiler-service.js';
 import {
@@ -87,6 +88,7 @@ import {GnatDebugTree as GnatDebugTreeView} from './panes/gnatdebugtree-view.js'
 import {RustMacroExp as RustMacroExpView} from './panes/rustmacroexp-view.js';
 import {IdentifierSet} from './identifier-set.js';
 import {EventMap} from './event-map.js';
+import {LanguageKey} from './languages.interfaces.js';
 
 type EventDescriptorMap = {
     [E in keyof EventMap]: [E, ...Parameters<EventMap[E]>];
@@ -107,50 +109,60 @@ export class Hub {
     public deferred = true;
     public deferredEmissions: EventDescriptor[] = [];
 
-    public lastOpenedLangId: string | null;
+    public lastOpenedLangId: LanguageKey | null;
     public subdomainLangId: string | undefined;
-    public defaultLangId: string;
+    public defaultLangId: LanguageKey;
 
     public constructor(
         public readonly layout: GoldenLayout,
         subLangId: string | undefined,
-        defaultLangId: string,
+        defaultLangId: LanguageKey,
     ) {
         this.lastOpenedLangId = null;
         this.subdomainLangId = subLangId;
         this.defaultLangId = defaultLangId;
         this.compilerService = new CompilerService(this.layout.eventHub);
 
-        layout.registerComponent(EDITOR_COMPONENT_NAME, (c, s) => this.codeEditorFactory(c, s));
-        layout.registerComponent(COMPILER_COMPONENT_NAME, (c, s) => this.compilerFactory(c, s));
-        layout.registerComponent(TREE_COMPONENT_NAME, (c, s) => this.treeFactory(c, s));
-        layout.registerComponent(EXECUTOR_COMPONENT_NAME, (c, s) => this.executorFactory(c, s));
-        layout.registerComponent(OUTPUT_COMPONENT_NAME, (c, s) => this.outputFactory(c, s));
-        layout.registerComponent(TOOL_COMPONENT_NAME, (c, s) => this.toolFactory(c, s));
-        layout.registerComponent(TOOL_INPUT_VIEW_COMPONENT_NAME, (c, s) => this.toolInputViewFactory(c, s));
-        layout.registerComponent(DIFF_VIEW_COMPONENT_NAME, (c, s) => this.diffFactory(c, s));
-        layout.registerComponent(OPT_VIEW_COMPONENT_NAME, (c, s) => this.optViewFactory(c, s));
-        layout.registerComponent(STACK_USAGE_VIEW_COMPONENT_NAME, (c, s) => this.stackUsageViewFactory(c, s));
-        layout.registerComponent(FLAGS_VIEW_COMPONENT_NAME, (c, s) => this.flagsViewFactory(c, s));
-        layout.registerComponent(PP_VIEW_COMPONENT_NAME, (c, s) => this.ppViewFactory(c, s));
-        layout.registerComponent(AST_VIEW_COMPONENT_NAME, (c, s) => this.astViewFactory(c, s));
-        layout.registerComponent(IR_VIEW_COMPONENT_NAME, (c, s) => this.irViewFactory(c, s));
-        layout.registerComponent(CLANGIR_VIEW_COMPONENT_NAME, (c, s) => this.clangirViewFactory(c, s));
-        layout.registerComponent(OPT_PIPELINE_VIEW_COMPONENT_NAME, (c, s) => this.optPipelineFactory(c, s));
+        layout.registerComponent(EDITOR_COMPONENT_NAME, (c: GLC, s: any) => this.codeEditorFactory(c, s));
+        layout.registerComponent(COMPILER_COMPONENT_NAME, (c: GLC, s: any) => this.compilerFactory(c, s));
+        layout.registerComponent(TREE_COMPONENT_NAME, (c: GLC, s: any) => this.treeFactory(c, s));
+        layout.registerComponent(EXECUTOR_COMPONENT_NAME, (c: GLC, s: any) => this.executorFactory(c, s));
+        layout.registerComponent(OUTPUT_COMPONENT_NAME, (c: GLC, s: any) => this.outputFactory(c, s));
+        layout.registerComponent(TOOL_COMPONENT_NAME, (c: GLC, s: any) => this.toolFactory(c, s));
+        layout.registerComponent(TOOL_INPUT_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.toolInputViewFactory(c, s));
+        layout.registerComponent(DIFF_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.diffFactory(c, s));
+        layout.registerComponent(OPT_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.optViewFactory(c, s));
+        layout.registerComponent(STACK_USAGE_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.stackUsageViewFactory(c, s));
+        layout.registerComponent(FLAGS_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.flagsViewFactory(c, s));
+        layout.registerComponent(PP_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.ppViewFactory(c, s));
+        layout.registerComponent(AST_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.astViewFactory(c, s));
+        layout.registerComponent(IR_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.irViewFactory(c, s));
+        layout.registerComponent(CLANGIR_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.clangirViewFactory(c, s));
+        layout.registerComponent(OPT_PIPELINE_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.optPipelineFactory(c, s));
         // Historical LLVM-specific name preserved to keep old links working
-        layout.registerComponent(LLVM_OPT_PIPELINE_VIEW_COMPONENT_NAME, (c, s) => this.optPipelineFactory(c, s));
-        layout.registerComponent(DEVICE_VIEW_COMPONENT_NAME, (c, s) => this.deviceViewFactory(c, s));
-        layout.registerComponent(RUST_MIR_VIEW_COMPONENT_NAME, (c, s) => this.rustMirViewFactory(c, s));
-        layout.registerComponent(HASKELL_CORE_VIEW_COMPONENT_NAME, (c, s) => this.haskellCoreViewFactory(c, s));
-        layout.registerComponent(HASKELL_STG_VIEW_COMPONENT_NAME, (c, s) => this.haskellStgViewFactory(c, s));
-        layout.registerComponent(HASKELL_CMM_VIEW_COMPONENT_NAME, (c, s) => this.haskellCmmViewFactory(c, s));
-        layout.registerComponent(GNAT_DEBUG_TREE_VIEW_COMPONENT_NAME, (c, s) => this.gnatDebugTreeViewFactory(c, s));
-        layout.registerComponent(GNAT_DEBUG_VIEW_COMPONENT_NAME, (c, s) => this.gnatDebugViewFactory(c, s));
-        layout.registerComponent(RUST_MACRO_EXP_VIEW_COMPONENT_NAME, (c, s) => this.rustMacroExpViewFactory(c, s));
-        layout.registerComponent(RUST_HIR_VIEW_COMPONENT_NAME, (c, s) => this.rustHirViewFactory(c, s));
-        layout.registerComponent(GCC_DUMP_VIEW_COMPONENT_NAME, (c, s) => this.gccDumpViewFactory(c, s));
-        layout.registerComponent(CFG_VIEW_COMPONENT_NAME, (c, s) => this.cfgViewFactory(c, s));
-        layout.registerComponent(CONFORMANCE_VIEW_COMPONENT_NAME, (c, s) => this.conformanceViewFactory(c, s));
+        layout.registerComponent(LLVM_OPT_PIPELINE_VIEW_COMPONENT_NAME, (c: GLC, s: any) =>
+            this.optPipelineFactory(c, s),
+        );
+        layout.registerComponent(DEVICE_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.deviceViewFactory(c, s));
+        layout.registerComponent(RUST_MIR_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.rustMirViewFactory(c, s));
+        layout.registerComponent(HASKELL_CORE_VIEW_COMPONENT_NAME, (c: GLC, s: any) =>
+            this.haskellCoreViewFactory(c, s),
+        );
+        layout.registerComponent(HASKELL_STG_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.haskellStgViewFactory(c, s));
+        layout.registerComponent(HASKELL_CMM_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.haskellCmmViewFactory(c, s));
+        layout.registerComponent(GNAT_DEBUG_TREE_VIEW_COMPONENT_NAME, (c: GLC, s: any) =>
+            this.gnatDebugTreeViewFactory(c, s),
+        );
+        layout.registerComponent(GNAT_DEBUG_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.gnatDebugViewFactory(c, s));
+        layout.registerComponent(RUST_MACRO_EXP_VIEW_COMPONENT_NAME, (c: GLC, s: any) =>
+            this.rustMacroExpViewFactory(c, s),
+        );
+        layout.registerComponent(RUST_HIR_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.rustHirViewFactory(c, s));
+        layout.registerComponent(GCC_DUMP_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.gccDumpViewFactory(c, s));
+        layout.registerComponent(CFG_VIEW_COMPONENT_NAME, (c: GLC, s: any) => this.cfgViewFactory(c, s));
+        layout.registerComponent(CONFORMANCE_VIEW_COMPONENT_NAME, (c: GLC, s: any) =>
+            this.conformanceViewFactory(c, s),
+        );
 
         layout.eventHub.on(
             'editorOpen',
@@ -210,7 +222,7 @@ export class Hub {
         );
         layout.eventHub.on(
             'languageChange',
-            function (this: Hub, editorId: number, langId: string) {
+            function (this: Hub, editorId: number, langId: LanguageKey) {
                 this.lastOpenedLangId = langId;
             },
             this,
@@ -385,7 +397,7 @@ export class Hub {
         }
     }
 
-    public activateTabForContainer(container?: GoldenLayout.Container) {
+    public activateTabForContainer(container?: GLC) {
         if (container && (container.tab as typeof container.tab | null)) {
             container.tab.header.parent.setActiveContentItem(container.tab.contentItem);
         }
diff --git a/static/lib-utils.ts b/static/lib-utils.ts
index efe162713..093de7f88 100644
--- a/static/lib-utils.ts
+++ b/static/lib-utils.ts
@@ -24,6 +24,7 @@
 
 import {options} from './options.js';
 import {LanguageLibs, Library} from './options.interfaces.js';
+import {Remote} from './compiler.interfaces.js';
 
 const LIB_MATCH_RE = /([\w-]*)\.([\w-]*)/i;
 
@@ -68,7 +69,7 @@ function copyAndFilterLibraries(allLibraries: LanguageLibs, filter: string[]) {
 export function getSupportedLibraries(
     supportedLibrariesArr: string[] | undefined,
     langId: string,
-    remote,
+    remote?: Remote,
 ): LanguageLibs {
     if (!remote) {
         const allLibs = options.libs[langId];
diff --git a/static/line-colouring.ts b/static/line-colouring.ts
index eaca95e3a..7a2491b57 100644
--- a/static/line-colouring.ts
+++ b/static/line-colouring.ts
@@ -24,6 +24,7 @@
 
 import _ from 'underscore';
 import {MultifileService} from './multifile-service.js';
+import {ResultLine} from './resultline/resultline.interfaces.js';
 
 interface ColouredSourcelineInfo {
     sourceLine: number;
@@ -50,7 +51,7 @@ export class LineColouring {
         this.linesAndColourByEditor = {};
     }
 
-    public addFromAssembly(compilerId, asm) {
+    public addFromAssembly(compilerId: number, asm: ResultLine[]) {
         let asmLineIdx = 0;
         for (const asmLine of asm) {
             if (asmLine.source && asmLine.source.line > 0) {
diff --git a/static/local.ts b/static/local.ts
index c3a11870f..a74e9580f 100644
--- a/static/local.ts
+++ b/static/local.ts
@@ -31,7 +31,7 @@ export interface Storage {
 
     set(key: string, value: string): boolean;
 
-    remove(key: string);
+    remove(key: string): void;
 }
 
 class LocalOnlyStorage implements Storage {
diff --git a/static/modes/carbon-mode.ts b/static/modes/carbon-mode.ts
index 0b6cf01a1..59e8b5f9e 100644
--- a/static/modes/carbon-mode.ts
+++ b/static/modes/carbon-mode.ts
@@ -23,6 +23,8 @@
 // POSSIBILITY OF SUCH DAMAGE.
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 function definition(): monaco.languages.IMonarchLanguage {
diff --git a/static/modes/cpp-for-opencl-mode.ts b/static/modes/cpp-for-opencl-mode.ts
index 596d5e4ca..398757d95 100644
--- a/static/modes/cpp-for-opencl-mode.ts
+++ b/static/modes/cpp-for-opencl-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 import * as cppp from './cppp-mode.js';
diff --git a/static/modes/cppcircle-mode.ts b/static/modes/cppcircle-mode.ts
index 68c66d365..270d6a7f7 100644
--- a/static/modes/cppcircle-mode.ts
+++ b/static/modes/cppcircle-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 import * as cppp from './cppp-mode.js';
 
diff --git a/static/modes/cppfront-mode.ts b/static/modes/cppfront-mode.ts
index be3909d7e..50f65dad4 100644
--- a/static/modes/cppfront-mode.ts
+++ b/static/modes/cppfront-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 import * as cppp from './cppp-mode.js';
 
@@ -52,7 +54,7 @@ function definition(): monaco.languages.IMonarchLanguage {
 
     // Generic parsers.
 
-    function parseCpp2Balanced(delimiters, delimiter, opener, closer) {
+    function parseCpp2Balanced(delimiters: string, delimiter: string, opener: RegExp, closer: RegExp) {
         return (cppfront.tokenizer['parse_cpp2_balanced_' + delimiters] = [
             {include: '@whitespace'},
             [opener, 'delimiter.' + delimiter, '$S2.$S3.$S4'],
@@ -91,7 +93,14 @@ function definition(): monaco.languages.IMonarchLanguage {
     }
 
     function setupLiteralParsers() {
-        cppfront.at_cpp2_interpolation = /\([^"]+\)\$/;
+        function balancedParenthesesRegex(max_nesting: number) {
+            const front = String.raw`\((?:[^\\()]*|`;
+            const back = String.raw`)*\)`;
+            return front.repeat(max_nesting + 1) + back.repeat(max_nesting + 1);
+        }
+        cppfront.at_cpp2_balanced_parentheses = balancedParenthesesRegex(5);
+
+        cppfront.at_cpp2_interpolation = /@at_cpp2_balanced_parentheses\$/;
         cppfront.tokenizer.parse_cpp2_interpolation = [
             [/(\()(.)/, ['delimiter.parenthesis', {token: '@rematch', next: 'parse_cpp2_expression'}]],
             [/:[^)]*/, 'string'],
@@ -107,7 +116,7 @@ function definition(): monaco.languages.IMonarchLanguage {
             [/@encoding?"/, {token: 'string', switchTo: '@string..cpp2'}],
         ];
 
-        function parseCpp2Interpolation(state, prefix_token_regex, token_class) {
+        function parseCpp2Interpolation(state: string, prefix_token_regex: RegExp, token_class: string) {
             cppfront.tokenizer[state].unshift([
                 prefix_token_regex.source + /(@at_cpp2_interpolation)/.source,
                 {
diff --git a/static/modes/cppp-mode.ts b/static/modes/cppp-mode.ts
index b2615e40d..d3535dfd7 100644
--- a/static/modes/cppp-mode.ts
+++ b/static/modes/cppp-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 // We need to create a new definition for cpp so we can remove invalid keywords
diff --git a/static/modes/cppx-blue-mode.ts b/static/modes/cppx-blue-mode.ts
index 4b50ee0d0..d83ddce13 100644
--- a/static/modes/cppx-blue-mode.ts
+++ b/static/modes/cppx-blue-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 import * as cppp from './cppp-mode.js';
 
diff --git a/static/modes/cuda-mode.ts b/static/modes/cuda-mode.ts
index 1a87ed423..c07d3ef88 100644
--- a/static/modes/cuda-mode.ts
+++ b/static/modes/cuda-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 import * as cppp from './cppp-mode.js';
 
diff --git a/static/modes/glsl-mode.ts b/static/modes/glsl-mode.ts
index 93c41c2ae..68861f23c 100644
--- a/static/modes/glsl-mode.ts
+++ b/static/modes/glsl-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 function definition(): monaco.languages.IMonarchLanguage {
diff --git a/static/modes/hlsl-mode.ts b/static/modes/hlsl-mode.ts
index 26e3918dd..0f2ff76bc 100644
--- a/static/modes/hlsl-mode.ts
+++ b/static/modes/hlsl-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 function definition(): monaco.languages.IMonarchLanguage {
diff --git a/static/modes/hylo-mode.ts b/static/modes/hylo-mode.ts
index a406add3c..974a9fced 100644
--- a/static/modes/hylo-mode.ts
+++ b/static/modes/hylo-mode.ts
@@ -23,6 +23,8 @@
 // POSSIBILITY OF SUCH DAMAGE.
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as swift from 'monaco-editor/esm/vs/basic-languages/swift/swift';
 
 function definition(): monaco.languages.IMonarchLanguage {
diff --git a/static/modes/ispc-mode.ts b/static/modes/ispc-mode.ts
index ea994f053..35a671db9 100644
--- a/static/modes/ispc-mode.ts
+++ b/static/modes/ispc-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 function definition(): monaco.languages.IMonarchLanguage {
diff --git a/static/modes/nc-mode.ts b/static/modes/nc-mode.ts
index 77e43ede4..1270fd1d1 100644
--- a/static/modes/nc-mode.ts
+++ b/static/modes/nc-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 // We need to ensure we use proper keywords for the Monaco Editor matcher. Note how
diff --git a/static/modes/openclc-mode.ts b/static/modes/openclc-mode.ts
index e446a85c2..b27ccc2e8 100644
--- a/static/modes/openclc-mode.ts
+++ b/static/modes/openclc-mode.ts
@@ -25,6 +25,8 @@
 import $ from 'jquery';
 
 import * as monaco from 'monaco-editor';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as cpp from 'monaco-editor/esm/vs/basic-languages/cpp/cpp';
 
 import * as nc from './nc-mode.js';
diff --git a/static/multifile-service.ts b/static/multifile-service.ts
index 2e35adbb5..eda461dc2 100644
--- a/static/multifile-service.ts
+++ b/static/multifile-service.ts
@@ -332,7 +332,7 @@ export class MultifileService {
         });
     }
 
-    public getEditorIdByFilename(filename: string): number | null {
+    public getEditorIdByFilename(filename: string | null): number | null {
         const file = this.files.find((file: MultifileFile) => {
             return file.isIncluded && file.filename === filename;
         });
diff --git a/static/options.interfaces.ts b/static/options.interfaces.ts
index 3ce46565c..1b3c1c889 100644
--- a/static/options.interfaces.ts
+++ b/static/options.interfaces.ts
@@ -64,7 +64,7 @@ export type Options = {
     release?: string;
     sentryEnvironment?: string;
     compileOptions: Record<LanguageKey, string>;
-    tools: Partial<Record<LanguageKey, Record<string, Tool>>>;
+    tools: Record<LanguageKey, Record<string, Tool>>;
     slides?: any[];
     cookieDomainRe: string;
     motdUrl: string;
diff --git a/static/options.ts b/static/options.ts
index 74e08a7da..5086c9fe7 100644
--- a/static/options.ts
+++ b/static/options.ts
@@ -35,7 +35,7 @@ window.staticRoot = unwrap(configElement.getAttribute('staticRoot'));
 
 const extraOptions: object = JSON.parse(decodeURIComponent(configElement.getAttribute('extraOptions') ?? '"%7B%7D"')); // Encoded {}
 for (const key in extraOptions) {
-    window.compilerExplorerOptions[key] = extraOptions[key];
+    window.compilerExplorerOptions[key] = extraOptions[key as keyof typeof extraOptions];
 }
 
 declare let __webpack_public_path__: string;
diff --git a/static/panes/ast-view.ts b/static/panes/ast-view.ts
index e0a2d8cd5..796c91ed9 100644
--- a/static/panes/ast-view.ts
+++ b/static/panes/ast-view.ts
@@ -36,6 +36,7 @@ import * as monacoConfig from '../monaco-config.js';
 import {Hub} from '../hub.js';
 import {unwrap} from '../assert.js';
 import {CompilerInfo} from '../compiler.interfaces.js';
+import {CompilationResult} from '../compilation/compilation.interfaces.js';
 
 type DecorationEntry = {
     linkedCode: any[];
@@ -168,7 +169,7 @@ export class Ast extends MonacoPane<monaco.editor.IStandaloneCodeEditor, AstStat
         return this.editor.getModel()?.getLanguageId();
     }
 
-    override onCompileResult(id: number, compiler, result) {
+    override onCompileResult(id: number, compiler: CompilerInfo, result: CompilationResult) {
         if (this.compilerInfo.compilerId !== id) return;
 
         if (result.astOutput) {
@@ -229,7 +230,7 @@ export class Ast extends MonacoPane<monaco.editor.IStandaloneCodeEditor, AstStat
 
     tryApplyAstColours(): void {
         if (!this.srcColours || !this.colourScheme || !this.astCode || this.astCode.length === 0) return;
-        const astColours = {};
+        const astColours: Record<number, number> = {};
         for (const [index, code] of this.astCode.entries()) {
             if (
                 code.source &&
diff --git a/static/panes/cfg-view.ts b/static/panes/cfg-view.ts
index 4cd7a1ea2..c561d2a11 100644
--- a/static/panes/cfg-view.ts
+++ b/static/panes/cfg-view.ts
@@ -176,7 +176,7 @@ export class Cfg extends Pane<CfgState> {
             dropdownParent: 'body',
             plugins: ['dropdown_input'],
             sortField: 'title',
-            onChange: e => this.selectFunction(e as unknown as string),
+            onChange: (e: string) => this.selectFunction(e),
         });
         this.functionSelector.on('dropdown_close', () => {
             // scroll back to the selection on the next open
diff --git a/static/panes/clangir-view.ts b/static/panes/clangir-view.ts
index 59df2f781..ecbd6e673 100644
--- a/static/panes/clangir-view.ts
+++ b/static/panes/clangir-view.ts
@@ -69,7 +69,10 @@ export class Clangir extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Cla
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('clangirViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/compiler.ts b/static/panes/compiler.ts
index 284467085..348913e1f 100644
--- a/static/panes/compiler.ts
+++ b/static/panes/compiler.ts
@@ -2692,8 +2692,8 @@ export class Compiler extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Co
 
         if (!this.compiler) return;
 
-        const addTool = (toolName: string, title: string, toolIcon?, toolIconDark?) => {
-            const btn = $("<button class='dropdown-item btn btn-light btn-sm new-pane-button'>");
+        const addTool = (toolName: string, title: string, toolIcon?: string, toolIconDark?: string) => {
+            const btn = $("<button class='dropdown-item btn btn-light btn-sm'>");
             btn.addClass('view-' + toolName);
             btn.data('toolname', toolName);
             if (toolIcon) {
@@ -2753,7 +2753,10 @@ export class Compiler extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Co
         const filters = this.getEffectiveFilters();
         // We can support intel output if the compiler supports it, or if we're compiling
         // to binary (as we can disassemble it however we like).
-        const formatFilterTitle = (button, title) => {
+        const formatFilterTitle = (
+            button: JQuery<HTMLElementTagNameMap[keyof HTMLElementTagNameMap]>,
+            title: JQuery<HTMLElement>,
+        ) => {
             button.prop(
                 'title',
                 '[' +
diff --git a/static/panes/device-view.ts b/static/panes/device-view.ts
index 7a4d2fca8..ae994bd93 100644
--- a/static/panes/device-view.ts
+++ b/static/panes/device-view.ts
@@ -362,7 +362,7 @@ export class DeviceAsm extends MonacoPane<monaco.editor.IStandaloneCodeEditor, D
 
         // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
         if (id === this.compilerInfo.compilerId && this.deviceCode) {
-            const irColours = {};
+            const irColours: Record<number, number> = {};
             this.deviceCode.forEach((x: ResultLine, index: number) => {
                 if (x.source && x.source.file == null && x.source.line > 0 && colours[x.source.line - 1]) {
                     irColours[index] = colours[x.source.line - 1];
diff --git a/static/panes/diff.ts b/static/panes/diff.ts
index 12f365af6..5fd7d8d20 100644
--- a/static/panes/diff.ts
+++ b/static/panes/diff.ts
@@ -90,9 +90,9 @@ class DiffStateObject {
         this.extraoption = extraoption;
     }
 
-    update(id: number | string, compiler, result: CompilationResult) {
+    update(id: number | string, compiler: CompilerInfo, result: CompilationResult) {
         if (this.id !== id) return false;
-        this.compiler = compiler;
+        this.compiler!.compiler = compiler;
         this.result = result;
         this.refresh();
 
@@ -320,7 +320,7 @@ export class Diff extends MonacoPane<monaco.editor.IStandaloneDiffEditor, DiffSt
         this.updateCompilers();
     }
 
-    getDiffableOptions(picker?, extraoptions?: DiffOption[]): any[] {
+    getDiffableOptions(picker?: HTMLSelectElement | TomSelect, extraoptions?: DiffOption[]): any[] {
         const options: DiffOption[] = [
             {id: DiffType.ASM.toString(), name: 'Assembly'},
             {id: DiffType.CompilerStdOut.toString(), name: 'Compiler stdout'},
diff --git a/static/panes/editor.interfaces.ts b/static/panes/editor.interfaces.ts
index e13e9ea42..3e2c735cb 100644
--- a/static/panes/editor.interfaces.ts
+++ b/static/panes/editor.interfaces.ts
@@ -22,7 +22,7 @@
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 
-import {Language} from '../../types/languages.interfaces.js';
+import {Language, LanguageKey} from '../../types/languages.interfaces.js';
 
 export type EditorState = {
     filename?: string;
@@ -30,7 +30,7 @@ export type EditorState = {
         readOnly?: boolean;
     };
     source?: string;
-    lang: string;
+    lang: LanguageKey;
 };
 
 export type LanguageSelectData = Language & {
diff --git a/static/panes/editor.ts b/static/panes/editor.ts
index a4a6ffd23..d01c218b8 100644
--- a/static/panes/editor.ts
+++ b/static/panes/editor.ts
@@ -81,7 +81,7 @@ export class Editor extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Edit
     private filename: string | false;
     private awaitingInitialResults: boolean;
     private revealJumpStack: editor.ICodeEditorViewState[];
-    private langKeys: string[];
+    private langKeys: LanguageKey[];
     private legacyReadOnly?: boolean;
     private selectize?: TomSelect;
     private lastChangeEmitted: string | null;
@@ -316,13 +316,13 @@ export class Editor extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Edit
         this.waitingForLanguage = Boolean(state.source && !state.lang);
         if (this.settings.defaultLanguage && this.settings.defaultLanguage in languages) {
             newLanguage = languages[this.settings.defaultLanguage];
-        } else if (this.hub.defaultLangId && this.hub.defaultLangId in languages) {
+        } else if (this.hub.defaultLangId in languages) {
             // the first time the user visits the site (or particular domain), this.settings might not be set yet
             //  use the hub's default lang if possible
             newLanguage = languages[this.hub.defaultLangId];
         }
 
-        if (state.lang && state.lang in languages) {
+        if (state.lang in languages) {
             newLanguage = languages[state.lang];
         } else if (
             this.settings.newEditorLastLang &&
@@ -498,7 +498,7 @@ export class Editor extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Edit
         super.initializeGlobalDependentProperties();
 
         this.httpRoot = window.httpRoot;
-        this.langKeys = Object.keys(languages);
+        this.langKeys = Object.keys(languages) as LanguageKey[];
     }
 
     override initializeStateDependentProperties(state: MonacoPaneState & EditorState): void {
@@ -598,7 +598,7 @@ export class Editor extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Edit
             return Components.getEditor(this.settings.defaultLanguage as any);
         };
 
-        const addPaneOpener = (dragSource, dragConfig) => {
+        const addPaneOpener = (dragSource: JQuery<HTMLElement>, dragConfig) => {
             this.container.layoutManager
                 .createDragSource(dragSource, dragConfig)
                 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
@@ -1523,7 +1523,7 @@ export class Editor extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Edit
                 if (obj.tag.link) {
                     link = {
                         value: obj.tag.link.text,
-                        target: obj.tag.link.url,
+                        target: obj.tag.link.url as unknown as monaco.Uri,
                     };
                 }
 
diff --git a/static/panes/executor.ts b/static/panes/executor.ts
index 4703172ad..ca9e59f7a 100644
--- a/static/panes/executor.ts
+++ b/static/panes/executor.ts
@@ -882,7 +882,7 @@ export class Executor extends Pane<ExecutorState> {
             LibUtils.getSupportedLibraries(
                 this.compiler ? this.compiler.libsArr : [],
                 this.currentLangId,
-                this.compiler?.remote ?? null,
+                this.compiler?.remote ?? undefined,
             ),
         );
     }
@@ -1248,7 +1248,7 @@ export class Executor extends Pane<ExecutorState> {
                 filteredLibraries = LibUtils.getSupportedLibraries(
                     this.compiler.libsArr,
                     this.currentLangId || '',
-                    this.compiler.remote ?? null,
+                    this.compiler.remote ?? undefined,
                 );
             }
 
diff --git a/static/panes/flags-view.ts b/static/panes/flags-view.ts
index 43e299f28..f6254400f 100644
--- a/static/panes/flags-view.ts
+++ b/static/panes/flags-view.ts
@@ -157,7 +157,7 @@ export class Flags extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Flags
         return state as MonacoPaneState;
     }
 
-    maybeEmitChange(force) {
+    maybeEmitChange(force: boolean) {
         const options = this.getOptions();
         if (!force && options === this.lastChangeEmitted) return;
 
diff --git a/static/panes/gccdump-view.ts b/static/panes/gccdump-view.ts
index c0d8150f0..d52fd395e 100644
--- a/static/panes/gccdump-view.ts
+++ b/static/panes/gccdump-view.ts
@@ -97,8 +97,8 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
             if (match) {
                 const selectedPassO: GccDumpViewSelectedPass = {
                     filename_suffix: match[1] + '.' + match[2],
-                    name: match[2] + ' (' + passType[match[1]] + ')',
-                    command_prefix: '-fdump-' + passType[match[1]] + '-' + match[2],
+                    name: match[2] + ' (' + passType[match[1] as keyof typeof passType] + ')',
+                    command_prefix: '-fdump-' + passType[match[1] as keyof typeof passType] + '-' + match[2],
 
                     // FIXME(dkm): maybe this could be avoided by better typing.
                     selectedPass: null,
@@ -256,7 +256,7 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
     }
 
     updateButtons() {
-        const formatButtonTitle = (button, title) =>
+        const formatButtonTitle = (button: JQuery<HTMLElement>, title: string) =>
             button.prop('title', '[' + (button.hasClass('active') ? 'ON' : 'OFF') + '] ' + title);
         formatButtonTitle(this.dumpTreesButton, this.dumpTreesTitle);
         formatButtonTitle(this.dumpRtlButton, this.dumpRtlTitle);
@@ -310,7 +310,7 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
 
     // Called after result from new compilation received
     // if gccDumpOutput is false, cleans the select menu
-    updatePass(filters, selectize, gccDumpOutput) {
+    updatePass(filters: Toggles, selectize: TomSelect, gccDumpOutput) {
         const passes = gccDumpOutput ? gccDumpOutput.all : [];
 
         // we are changing selectize but don't want any callback to
@@ -323,10 +323,10 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
             selectize.addOption(p);
         }
 
-        if (gccDumpOutput.selectedPass) selectize.addItem(gccDumpOutput.selectedPass.name, true);
-        else selectize.clear(true);
-
-        this.eventHub.emit('gccDumpPassSelected', this.compilerInfo.compilerId, gccDumpOutput.selectedPass, false);
+        if (gccDumpOutput && gccDumpOutput.selectedPass) {
+            selectize.addItem(gccDumpOutput.selectedPass.name, true);
+            this.eventHub.emit('gccDumpPassSelected', this.compilerInfo.compilerId, gccDumpOutput.selectedPass, false);
+        } else selectize.clear(true);
 
         this.inhibitPassSelect = false;
     }
@@ -362,7 +362,7 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
         } else {
             this.selectize.clear(true);
             this.selectedPass = null;
-            this.updatePass(this.filters, this.selectize, false);
+            this.updatePass(this.filters, this.selectize, null);
             this.uiIsReady = false;
             this.onUiNotReady();
             if (!compiler.supportsGccDump) {
@@ -374,7 +374,7 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
         this.updateState();
     }
 
-    showGccDumpResults(results) {
+    showGccDumpResults(results: string) {
         this.editor.setValue(results);
 
         if (!this.isAwaitingInitialResults) {
@@ -386,7 +386,13 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
         }
     }
 
-    override onCompiler(compilerId: number, compiler, options: unknown, editorId: number, treeId: number) {
+    override onCompiler(
+        compilerId: number,
+        compiler: CompilerInfo | null,
+        options: unknown,
+        editorId: number,
+        treeId: number,
+    ) {
         if (compilerId === this.compilerInfo.compilerId) {
             this.compilerInfo.compilerName = compiler ? compiler.name : '';
             this.compilerInfo.editorId = editorId;
@@ -397,12 +403,12 @@ export class GccDump extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Gcc
         }
     }
 
-    override onCompilerClose(id) {
+    override onCompilerClose(id: number) {
         if (id === this.compilerInfo.compilerId) {
             // We can't immediately close as an outer loop somewhere in GoldenLayout is iterating over
             // the hierarchy. We can't modify while it's being iterated over.
             this.close();
-            _.defer(function (self) {
+            _.defer(function (self: GccDump) {
                 self.container.close();
             }, this);
         }
diff --git a/static/panes/gnatdebug-view.ts b/static/panes/gnatdebug-view.ts
index 4c97e842f..34a3f0bae 100644
--- a/static/panes/gnatdebug-view.ts
+++ b/static/panes/gnatdebug-view.ts
@@ -70,7 +70,10 @@ export class GnatDebug extends MonacoPane<monaco.editor.IStandaloneCodeEditor, G
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('gnatDebugViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/gnatdebugtree-view.ts b/static/panes/gnatdebugtree-view.ts
index 05bfe5117..07fe70b76 100644
--- a/static/panes/gnatdebugtree-view.ts
+++ b/static/panes/gnatdebugtree-view.ts
@@ -70,7 +70,10 @@ export class GnatDebugTree extends MonacoPane<monaco.editor.IStandaloneCodeEdito
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('gnatDebugTreeViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/haskellcmm-view.ts b/static/panes/haskellcmm-view.ts
index 9eee9df8b..6fba666c1 100644
--- a/static/panes/haskellcmm-view.ts
+++ b/static/panes/haskellcmm-view.ts
@@ -69,7 +69,10 @@ export class HaskellCmm extends MonacoPane<monaco.editor.IStandaloneCodeEditor,
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('haskellCmmViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/haskellcore-view.ts b/static/panes/haskellcore-view.ts
index 80bfd3784..e4cdcb7ee 100644
--- a/static/panes/haskellcore-view.ts
+++ b/static/panes/haskellcore-view.ts
@@ -69,7 +69,10 @@ export class HaskellCore extends MonacoPane<monaco.editor.IStandaloneCodeEditor,
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('haskellCoreViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/haskellstg-view.ts b/static/panes/haskellstg-view.ts
index fbcda8394..6af6e9e71 100644
--- a/static/panes/haskellstg-view.ts
+++ b/static/panes/haskellstg-view.ts
@@ -69,7 +69,10 @@ export class HaskellStg extends MonacoPane<monaco.editor.IStandaloneCodeEditor,
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('haskellStgViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/ir-view.ts b/static/panes/ir-view.ts
index 9851866e8..f7ac38ea9 100644
--- a/static/panes/ir-view.ts
+++ b/static/panes/ir-view.ts
@@ -312,8 +312,9 @@ export class Ir extends MonacoPane<monaco.editor.IStandaloneCodeEditor, IrState>
         };
         let changed = false;
         for (const k in newOptions) {
-            if (newOptions[k] !== this.lastOptions[k]) {
+            if (newOptions[k as keyof LLVMIrBackendOptions] !== this.lastOptions[k as keyof LLVMIrBackendOptions]) {
                 changed = true;
+                break;
             }
         }
         this.lastOptions = newOptions;
diff --git a/static/panes/opt-pipeline.ts b/static/panes/opt-pipeline.ts
index 3577e5776..e68ebbd2b 100644
--- a/static/panes/opt-pipeline.ts
+++ b/static/panes/opt-pipeline.ts
@@ -120,7 +120,7 @@ export class OptPipeline extends MonacoPane<monaco.editor.IStandaloneDiffEditor,
             plugins: ['input_autogrow'],
             sortField: 'title',
             maxOptions: 1000,
-            onChange: e => this.selectGroup(e as string),
+            onChange: (e: string) => this.selectGroup(e),
         });
         this.groupSelector.on('dropdown_close', () => {
             // scroll back to the selection on the next open
@@ -289,7 +289,8 @@ export class OptPipeline extends MonacoPane<monaco.editor.IStandaloneDiffEditor,
         };
         let changed = false;
         for (const k in newOptions) {
-            if (newOptions[k] !== this.lastOptions[k]) {
+            const key = k as keyof OptPipelineBackendOptions;
+            if (newOptions[key] !== this.lastOptions[key]) {
                 changed = true;
             }
         }
diff --git a/static/panes/output.ts b/static/panes/output.ts
index 6cdee538a..053b2fd0f 100644
--- a/static/panes/output.ts
+++ b/static/panes/output.ts
@@ -37,7 +37,7 @@ import {CompilationResult} from '../../types/compilation/compilation.interfaces.
 import {CompilerInfo} from '../../types/compiler.interfaces.js';
 import {escapeHTML} from '../../shared/common-utils.js';
 
-function makeAnsiToHtml(color?) {
+function makeAnsiToHtml(color?: string) {
     return new AnsiToHtml.Filter({
         fg: color ? color : '#333',
         bg: '#f5f5f5',
@@ -251,7 +251,7 @@ export class Output extends Pane<OutputState> {
         if (color) elem.css('color', color);
     }
 
-    getEditorIdByFilename(filename) {
+    getEditorIdByFilename(filename: string) {
         if (this.compilerInfo.treeId) {
             const tree = this.hub.getTreeById(this.compilerInfo.treeId);
             if (tree) {
@@ -261,7 +261,7 @@ export class Output extends Pane<OutputState> {
         }
     }
 
-    emitEditorLinkLine(lineNum, column, filename, goto) {
+    emitEditorLinkLine(lineNum: number, column: number, filename: string, goto: boolean) {
         if (this.compilerInfo.editorId) {
             this.eventHub.emit('editorLinkLine', this.compilerInfo.editorId, lineNum, column, column + 1, goto);
         } else if (filename) {
@@ -274,7 +274,7 @@ export class Output extends Pane<OutputState> {
 
     add(msg: string, lineNum?: number, column?: number, filename?: string) {
         const elem = $('<div/>').appendTo(this.contentRoot);
-        if (lineNum) {
+        if (lineNum && column && filename) {
             elem.empty();
             $('<span class="linked-compiler-output-line"></span>')
                 .html(msg)
@@ -302,7 +302,7 @@ export class Output extends Pane<OutputState> {
         return `(Compiler #${this.compilerInfo.compilerId})`;
     }
 
-    override onCompilerClose(id) {
+    override onCompilerClose(id: number) {
         if (id === this.compilerInfo.compilerId) {
             // We can't immediately close as an outer loop somewhere in GoldenLayout is iterating over
             // the hierarchy. We can't modify while it's being iterated over.
@@ -320,7 +320,7 @@ export class Output extends Pane<OutputState> {
         $(document).off('keydown', this.keydownCallback);
     }
 
-    setCompileStatus(isCompiling) {
+    setCompileStatus(isCompiling: boolean) {
         this.contentRoot.toggleClass('compiling', isCompiling);
     }
 
diff --git a/static/panes/pp-view.ts b/static/panes/pp-view.ts
index d4db07b22..d7abce5a0 100644
--- a/static/panes/pp-view.ts
+++ b/static/panes/pp-view.ts
@@ -33,7 +33,7 @@ import {Container} from 'golden-layout';
 import {MonacoPaneState} from './pane.interfaces.js';
 import {Hub} from '../hub.js';
 import {unwrap} from '../assert.js';
-import {CompilationResult} from '../compilation/compilation.interfaces.js';
+import {CompilationResult, PPOutput} from '../compilation/compilation.interfaces.js';
 import {CompilerInfo} from '../compiler.interfaces.js';
 
 export class PP extends MonacoPane<monaco.editor.IStandaloneCodeEditor, PPViewState> {
@@ -129,7 +129,7 @@ export class PP extends MonacoPane<monaco.editor.IStandaloneCodeEditor, PPViewSt
         return this.editor.getModel()?.getLanguageId();
     }
 
-    showPpResults(results) {
+    showPpResults(results: PPOutput | string) {
         if (typeof results === 'object') {
             if (results.numberOfLinesFiltered > 0) {
                 this.editor.setValue(
@@ -180,12 +180,12 @@ export class PP extends MonacoPane<monaco.editor.IStandaloneCodeEditor, PPViewSt
         return state;
     }
 
-    override onCompilerClose(id) {
+    override onCompilerClose(id: number) {
         if (id === this.compilerInfo.compilerId) {
             // We can't immediately close as an outer loop somewhere in GoldenLayout is iterating over
             // the hierarchy. We can't modify while it's being iterated over.
             this.close();
-            _.defer(function (self) {
+            _.defer(function (self: PP) {
                 self.container.close();
             }, this);
         }
diff --git a/static/panes/rusthir-view.ts b/static/panes/rusthir-view.ts
index ff5de74cb..04c293592 100644
--- a/static/panes/rusthir-view.ts
+++ b/static/panes/rusthir-view.ts
@@ -69,7 +69,10 @@ export class RustHir extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Rus
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('rustHirViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/rustmacroexp-view.ts b/static/panes/rustmacroexp-view.ts
index d9325e4df..285d98409 100644
--- a/static/panes/rustmacroexp-view.ts
+++ b/static/panes/rustmacroexp-view.ts
@@ -69,7 +69,10 @@ export class RustMacroExp extends MonacoPane<monaco.editor.IStandaloneCodeEditor
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('rustMacroExpViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/rustmir-view.ts b/static/panes/rustmir-view.ts
index 6bc6583ac..d298657c3 100644
--- a/static/panes/rustmir-view.ts
+++ b/static/panes/rustmir-view.ts
@@ -69,7 +69,10 @@ export class RustMir extends MonacoPane<monaco.editor.IStandaloneCodeEditor, Rus
     }
 
     override registerCallbacks(): void {
-        const throttleFunction = _.throttle(event => this.onDidChangeCursorSelection(event), 500);
+        const throttleFunction = _.throttle(
+            (event: monaco.editor.ICursorSelectionChangedEvent) => this.onDidChangeCursorSelection(event),
+            500,
+        );
         this.editor.onDidChangeCursorSelection(event => throttleFunction(event));
         this.eventHub.emit('rustMirViewOpened', this.compilerInfo.compilerId);
         this.eventHub.emit('requestSettings');
diff --git a/static/panes/stack-usage-view.ts b/static/panes/stack-usage-view.ts
index 872060f6a..a49f2dae7 100644
--- a/static/panes/stack-usage-view.ts
+++ b/static/panes/stack-usage-view.ts
@@ -179,7 +179,7 @@ export class StackUsage extends MonacoPane<monaco.editor.IStandaloneCodeEditor,
         this.editorDecorations.set(suDecorations);
     }
 
-    override onCompiler(id: number, compiler) {
+    override onCompiler(id: number, compiler: CompilerInfo | null) {
         if (id === this.compilerInfo.compilerId) {
             this.compilerInfo.compilerName = compiler ? compiler.name : '';
             this.updateTitle();
diff --git a/static/panes/tool-input-view.ts b/static/panes/tool-input-view.ts
index 53575819d..b6da557c1 100644
--- a/static/panes/tool-input-view.ts
+++ b/static/panes/tool-input-view.ts
@@ -33,6 +33,7 @@ import {Hub} from '../hub.js';
 import {ToolInputViewState} from './tool-input-view.interfaces.js';
 import {CompilationResult} from '../compilation/compilation.interfaces.js';
 import {CompilerInfo} from '../compiler.interfaces.js';
+import {SiteSettings} from '../settings.js';
 
 export class ToolInputView extends MonacoPane<monaco.editor.IStandaloneCodeEditor, ToolInputViewState> {
     _toolId: string;
@@ -131,45 +132,45 @@ export class ToolInputView extends MonacoPane<monaco.editor.IStandaloneCodeEdito
         this.editor.dispose();
     }
 
-    onToolClose(compilerId, toolSettings) {
+    onToolClose(compilerId: number, toolSettings: ToolState) {
         if (this.compilerInfo.compilerId === compilerId && this._toolId === toolSettings.toolId) {
             // We can't immediately close as an outer loop somewhere in GoldenLayout is iterating over
             // the hierarchy. We can't modify while it's being iterated over.
             this.close();
-            _.defer(function (self) {
+            _.defer(function (self: ToolInputView) {
                 self.container.close();
             }, this);
         }
     }
 
-    onToolInputViewCloseRequest(compilerId, toolId) {
+    onToolInputViewCloseRequest(compilerId: number, toolId: string) {
         if (this.compilerInfo.compilerId === compilerId && this._toolId === toolId) {
             this.close();
-            _.defer(function (self) {
+            _.defer(function (self: ToolInputView) {
                 self.container.close();
             }, this);
         }
     }
 
-    override onCompilerClose(id) {
+    override onCompilerClose(id: number) {
         if (id === this.compilerInfo.compilerId) {
             // We can't immediately close as an outer loop somewhere in GoldenLayout is iterating over
             // the hierarchy. We can't modify while it's being iterated over.
             this.close();
-            _.defer(function (self) {
+            _.defer(function (self: ToolInputView) {
                 self.container.close();
             }, this);
         }
     }
 
-    override onSettingsChange(newSettings) {
+    override onSettingsChange(newSettings: SiteSettings) {
         super.onSettingsChange(newSettings);
         this.debouncedEmitChange = _.debounce(() => {
             this.maybeEmitChange(false);
         }, newSettings.delayAfterChange);
     }
 
-    override onDidChangeCursorSelection(e) {
+    override onDidChangeCursorSelection(e: monaco.editor.ICursorSelectionChangedEvent) {
         // On initialization this callback fires with the default selection
         // overwriting any selection from state. If we are awaiting initial
         // selection setting then don't update our selection.
@@ -179,7 +180,7 @@ export class ToolInputView extends MonacoPane<monaco.editor.IStandaloneCodeEdito
         }
     }
 
-    onSetToolInput(compilerId, toolId, value) {
+    onSetToolInput(compilerId: number, toolId: string, value: string) {
         if (this.compilerInfo.compilerId === compilerId && this._toolId === toolId) {
             const ret = this.editor.getModel()?.setValue(value);
             if (this.shouldSetSelectionInitially && this.selection) {
@@ -198,7 +199,7 @@ export class ToolInputView extends MonacoPane<monaco.editor.IStandaloneCodeEdito
         return this.editor.getModel()?.getValue() ?? '';
     }
 
-    maybeEmitChange(force) {
+    maybeEmitChange(force: boolean) {
         const input = this.getInput();
         if (!force && input === this.lastChangeEmitted) return;
 
diff --git a/static/panes/tool.ts b/static/panes/tool.ts
index 7400a73cb..8d1791aa0 100644
--- a/static/panes/tool.ts
+++ b/static/panes/tool.ts
@@ -183,7 +183,7 @@ export class Tool extends MonacoPane<monaco.editor.IStandaloneCodeEditor, ToolSt
     onLanguageChange(editorId: number | boolean, newLangId: LanguageKey) {
         if (this.compilerInfo.editorId && this.compilerInfo.editorId === editorId) {
             const tools = ceoptions.tools[newLangId];
-            this.toggleUsable(!!tools && !!tools[this.toolId]);
+            this.toggleUsable(!!tools[this.toolId]);
         }
     }
 
@@ -368,7 +368,7 @@ export class Tool extends MonacoPane<monaco.editor.IStandaloneCodeEditor, ToolSt
             monacoEditorHasBeenAutoOpened: this.monacoEditorHasBeenAutoOpened,
             argsPanelShown: !this.panelArgs.hasClass('d-none'),
         };
-        return state as MonacoPaneState;
+        return state;
     }
 
     setLanguage(languageId: false | string) {
diff --git a/static/panes/tree.ts b/static/panes/tree.ts
index 238e213d0..4dbf6d5a8 100644
--- a/static/panes/tree.ts
+++ b/static/panes/tree.ts
@@ -41,6 +41,7 @@ import _ from 'underscore';
 import {assert, unwrap, unwrapString} from '../assert.js';
 import {escapeHTML} from '../../shared/common-utils.js';
 import {LanguageKey} from '../languages.interfaces.js';
+import {ResultLine} from '../resultline/resultline.interfaces.js';
 
 const languages = options.languages;
 
@@ -69,7 +70,7 @@ export class Tree {
     private lineColouring: LineColouring;
     private readonly ourCompilers: Record<number, boolean>;
     private readonly busyCompilers: Record<number, boolean>;
-    private readonly asmByCompiler: Record<number, any>;
+    private readonly asmByCompiler: Record<number, ResultLine[]>;
     private selectize: TomSelect;
     private languageBtn: JQuery;
     private toggleCMakeButton: Toggles;
@@ -650,9 +651,7 @@ export class Tree {
         this.lineColouring.clear();
 
         for (const [compilerId, asm] of Object.entries(this.asmByCompiler)) {
-            if (asm) {
-                this.lineColouring.addFromAssembly(parseInt(compilerId), asm);
-            }
+            this.lineColouring.addFromAssembly(parseInt(compilerId), asm);
         }
 
         this.lineColouring.calculate();
diff --git a/static/print-view.ts b/static/print-view.ts
index b33bcd2be..d241e0152 100644
--- a/static/print-view.ts
+++ b/static/print-view.ts
@@ -60,7 +60,7 @@ export class Printerinator {
                 .slice(css.indexOf('.mtk1'))
                 .trim()
                 .split('\n')
-                .map(line => '#printview ' + line)
+                .map((line: string) => '#printview ' + line)
                 .join('\n');
             this.themer.setTheme(unwrap(theme));
         }
diff --git a/static/rison.ts b/static/rison.ts
index 91b8c39a9..2a52e6d25 100644
--- a/static/rison.ts
+++ b/static/rison.ts
@@ -148,7 +148,7 @@ class Encoders {
         if (id_ok.test(x)) return x;
 
         x = x.replace(/(['!])/g, function (a, b) {
-            if (string_table[b]) return '!' + b;
+            if (string_table[b as keyof typeof string_table]) return '!' + b;
             return b;
         });
         return "'" + x + "'";
@@ -293,7 +293,7 @@ class Parser {
                 const s = this.string;
                 const c = s.charAt(this.index++);
                 if (!c) return this.error('"!" at end of input');
-                const x = Parser.bangs[c];
+                const x = Parser.bangs[c as keyof typeof Parser.bangs];
                 if (typeof x == 'function') {
                     // eslint-disable-next-line no-useless-call
                     return x.call(null, this);
@@ -368,7 +368,7 @@ class Parser {
                         permittedSigns = '';
                         continue;
                     }
-                    state = transitions[state + '+' + c.toLowerCase()];
+                    state = transitions[(state + '+' + c.toLowerCase()) as keyof typeof transitions];
                     if (state === 'exp') permittedSigns = '-';
                 } while (state);
                 this.index = --i;
diff --git a/static/sentry.ts b/static/sentry.ts
index 84f07c82a..407bd14dd 100644
--- a/static/sentry.ts
+++ b/static/sentry.ts
@@ -30,13 +30,14 @@ import * as Sentry from '@sentry/browser';
 
 import GoldenLayout from 'golden-layout';
 import {serialiseState} from './url.js';
+import {SiteSettings} from './settings.js';
 
 let layout: GoldenLayout;
 let allowSendCode: boolean;
 
 export function setSentryLayout(l: GoldenLayout) {
     layout = l;
-    layout.eventHub.on('settingsChange', newSettings => {
+    layout.eventHub.on('settingsChange', (newSettings: SiteSettings) => {
         allowSendCode = newSettings.allowStoreCodeDebug;
     });
 
diff --git a/static/settings.ts b/static/settings.ts
index 6520a5136..845e6c096 100644
--- a/static/settings.ts
+++ b/static/settings.ts
@@ -138,11 +138,11 @@ interface SliderSettings {
     max: number;
     step: number;
     display: JQuery;
-    formatter: (number) => string;
+    formatter: (arg: number) => string;
 }
 
 class Slider extends BaseSetting {
-    private readonly formatter: (number) => string;
+    private readonly formatter: (arg: number) => string;
     private display: JQuery;
     private max: number;
     private min: number;
diff --git a/static/sharing.ts b/static/sharing.ts
index 7d5fd8187..76ed7ecb9 100644
--- a/static/sharing.ts
+++ b/static/sharing.ts
@@ -48,7 +48,7 @@ const shareServices = {
         embedValid: false,
         logoClass: 'fab fa-twitter',
         cssClass: 'share-twitter',
-        getLink: (title, url) => {
+        getLink: (title: string, url: string) => {
             return (
                 'https://twitter.com/intent/tweet' +
                 `?text=${encodeURIComponent(title)}` +
@@ -62,7 +62,7 @@ const shareServices = {
         embedValid: false,
         logoClass: 'fab fa-reddit',
         cssClass: 'share-reddit',
-        getLink: (title, url) => {
+        getLink: (title: string, url: string) => {
             return (
                 'http://www.reddit.com/submit' +
                 `?url=${encodeURIComponent(url)}` +
@@ -344,7 +344,7 @@ export class Sharing {
                 done(null, window.location.origin + root + '#' + url.serialiseState(config), false);
                 return;
             case LinkType.Embed: {
-                const options = {};
+                const options: Record<string, boolean> = {};
                 $('#sharelinkdialog input:checked').each((i, element) => {
                     options[$(element).prop('class')] = true;
                 });
@@ -380,7 +380,12 @@ export class Sharing {
         });
     }
 
-    private static getEmbeddedHtml(config, root, isReadOnly, extraOptions): string {
+    private static getEmbeddedHtml(
+        config: any,
+        root: string,
+        isReadOnly: boolean,
+        extraOptions: Record<string, boolean>,
+    ): string {
         const embedUrl = Sharing.getEmbeddedUrl(config, root, isReadOnly, extraOptions);
         // The attributes must be double quoted, the full url's rison contains single quotes
         return `<iframe width="800px" height="200px" src="${embedUrl}"></iframe>`;
diff --git a/static/tests/frontend-testing.interfaces.ts b/static/tests/frontend-testing.interfaces.ts
index eb738dcc1..b0ff68e05 100644
--- a/static/tests/frontend-testing.interfaces.ts
+++ b/static/tests/frontend-testing.interfaces.ts
@@ -28,7 +28,7 @@ export interface ITestable {
 }
 
 export interface IFrontendTesting {
-    add(test: ITestable);
+    add(test: ITestable): void;
     getAllTestNames(): string[];
     run(testToRun: string): Promise<void>;
 }
diff --git a/static/tests/motd.ts b/static/tests/motd.ts
index ad2ceadcb..2999a33ad 100644
--- a/static/tests/motd.ts
+++ b/static/tests/motd.ts
@@ -26,16 +26,19 @@ import {assert} from 'chai';
 import {isValidAd} from '../motd.js';
 import {ITestable} from './frontend-testing.interfaces.js';
 
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore  "Could not find a declaration file"
 import * as sinon from '../../node_modules/sinon/pkg/sinon-esm.js';
+import {Ad} from '../motd.interfaces.js';
 
 class MotdTests implements ITestable {
     public readonly description: string = 'motd';
 
-    private static assertAd(ad, subLang, expected, message) {
+    private static assertAd(ad: Ad, subLang, expected: boolean, message: string) {
         assert.equal(isValidAd(ad, subLang), expected, message);
     }
 
-    private static assertAdWithDateNow(dateNow, ad, subLang, expected, message) {
+    private static assertAdWithDateNow(dateNow: number, ad: Ad, subLang, expected: boolean, message: string) {
         const dateNowStub = sinon.stub(Date, 'now');
         dateNowStub.returns(dateNow);
         MotdTests.assertAd(ad, subLang, expected, message);
diff --git a/static/utils.ts b/static/utils.ts
index f1ec9b6c7..b041f82e6 100644
--- a/static/utils.ts
+++ b/static/utils.ts
@@ -41,7 +41,7 @@ export function updateAndCalcTopBarHeight(domRoot: JQuery, topBar: JQuery, hidea
 }
 
 export function formatDateTimeWithSpaces(d: Date) {
-    const t = x => x.slice(-2);
+    const t = (x: string) => x.slice(-2);
     // Hopefully some day we can use the temporal api to make this less of a pain
     return (
         `${d.getFullYear()} ${t('0' + (d.getMonth() + 1))} ${t('0' + d.getDate())}` +
@@ -92,8 +92,8 @@ function parseNumericValue(value: string): bigInt.BigInteger | null {
 }
 
 export function getNumericToolTip(value: string, digitSeparator?: string): string | null {
-    const formatNumber = (number, base, chunkSize) => {
-        const numberString = number.toString(base).toUpperCase();
+    const formatNumber = (num: bigInt.BigInteger, base: number, chunkSize: number) => {
+        const numberString = num.toString(base).toUpperCase();
         if (digitSeparator !== undefined) {
             return addDigitSeparator(numberString, digitSeparator, chunkSize);
         } else {
diff --git a/static/widgets/alert.interfaces.ts b/static/widgets/alert.interfaces.ts
index 6b842090f..f401fad2e 100644
--- a/static/widgets/alert.interfaces.ts
+++ b/static/widgets/alert.interfaces.ts
@@ -74,5 +74,5 @@ export interface AlertNotifyOptions {
     /**
      * onLoadHandler(element)
      */
-    onBeforeShow?: (any) => void;
+    onBeforeShow?: (arg: any) => void;
 }
diff --git a/static/widgets/compiler-picker.ts b/static/widgets/compiler-picker.ts
index a4497655c..7d77017cd 100644
--- a/static/widgets/compiler-picker.ts
+++ b/static/widgets/compiler-picker.ts
@@ -45,11 +45,11 @@ export class CompilerPicker {
     eventHub: EventHub;
     id: number;
     compilerService: CompilerService;
-    onCompilerChange: (x: string) => any;
+    onCompilerChange: (x: string) => void;
     tomSelect: TomSelect | null;
     lastLangId: string;
     lastCompilerId: string;
-    compilerIsVisible: (any) => any; // TODO => bool probably
+    compilerIsVisible: (ci: CompilerInfo) => boolean;
     popup: CompilerPickerPopup;
     toolbarPopoutButton: JQuery<HTMLElement>;
     popupTooltip: JQuery<HTMLElement>;
@@ -58,8 +58,8 @@ export class CompilerPicker {
         hub: Hub,
         langId: string,
         compilerId: string,
-        onCompilerChange: (x: string) => any,
-        compilerIsVisible?: (x: any) => any,
+        onCompilerChange: (x: string) => void,
+        compilerIsVisible?: (x: CompilerInfo) => boolean,
     ) {
         this.eventHub = hub.createEventHub();
         this.id = CompilerPicker.nextSelectorId++;
@@ -116,12 +116,12 @@ export class CompilerPicker {
             closeAfterSelect: true,
             plugins: ['dropdown_input'],
             maxOptions: 1000,
-            onChange: val => {
+            onChange: (val: string) => {
                 // TODO(jeremy-rifkin) I don't think this can be undefined.
                 // Typing here needs improvement later anyway.
                 /* eslint-disable-next-line @typescript-eslint/no-unnecessary-condition */
                 if (val) {
-                    const compilerId = val as string;
+                    const compilerId = val;
                     this.onCompilerChange(compilerId);
                     this.lastCompilerId = compilerId;
                 }
diff --git a/static/widgets/load-save.ts b/static/widgets/load-save.ts
index 11a8483b6..a80464b75 100644
--- a/static/widgets/load-save.ts
+++ b/static/widgets/load-save.ts
@@ -38,7 +38,7 @@ type PopulateItem = {name: string; load: () => void; delete?: () => void; overwr
 export class LoadSave {
     private modal: JQuery | null = null;
     private alertSystem: Alert;
-    private onLoadCallback: (...any) => void = _.identity;
+    private onLoadCallback: (...args: any) => void = _.identity;
     private editorText = '';
     private extension = '.txt';
     private base: string;
diff --git a/static/widgets/toggles.ts b/static/widgets/toggles.ts
index 5c11cf72e..6682fa6e8 100644
--- a/static/widgets/toggles.ts
+++ b/static/widgets/toggles.ts
@@ -66,7 +66,9 @@ export class Toggles extends EventEmitter {
 
             // Inject the icon if applicable
             if (button.find('.state-icon').length === 0) {
-                button.prepend('<i class="state-icon ' + settings[button.data('state')].icon + '"></i> ');
+                button.prepend(
+                    '<i class="state-icon ' + settings[button.data('state') as keyof typeof settings].icon + '"></i> ',
+                );
             }
         }
     }
@@ -84,7 +86,7 @@ export class Toggles extends EventEmitter {
         button
             .find('.state-icon')
             .removeClass()
-            .addClass(`state-icon ${settings[button.data('state')].icon}`);
+            .addClass(`state-icon ${settings[button.data('state') as keyof typeof settings].icon}`);
 
         // Update the button's color
         button.toggleClass('active', isChecked);
diff --git a/test/compilers/hook-tests.ts b/test/compilers/hook-tests.ts
index 7d811307f..6f79b51a5 100644
--- a/test/compilers/hook-tests.ts
+++ b/test/compilers/hook-tests.ts
@@ -83,7 +83,7 @@ describe('Hook compiler', () => {
                     labels: [],
                     source: {
                         file: null,
-                        line: undefined,
+                        line: null,
                     },
                     text: '; main in /app/example.hk at 0x56554a556550',
                 },
@@ -91,7 +91,7 @@ describe('Hook compiler', () => {
                     labels: [],
                     source: {
                         file: null,
-                        line: undefined,
+                        line: null,
                     },
                     text: '; 0 parameter(s), 0 non-local(s), 0 constant(s), 0 function(s)',
                 },
@@ -147,7 +147,7 @@ describe('Hook compiler', () => {
                     labels: [],
                     source: {
                         file: null,
-                        line: undefined,
+                        line: null,
                     },
                     text: '; 6 instruction(s)',
                 },
diff --git a/test/java-tests.ts b/test/java-tests.ts
index 9eb85d574..490de5371 100644
--- a/test/java-tests.ts
+++ b/test/java-tests.ts
@@ -159,7 +159,9 @@ describe('javap parsing', () => {
             asm: '<Compilation failed>',
         };
 
-        await expect(compiler.processAsm(result)).resolves.toEqual([{text: '<Compilation failed>', source: null}]);
+        await expect(compiler.processAsm(result)).resolves.toEqual({
+            asm: [{text: '<Compilation failed>', source: null}],
+        });
     });
 
     it('Parses simple class with one method', () => {
diff --git a/types/compilation/cfg.interfaces.ts b/types/compilation/cfg.interfaces.ts
index b47aadc9e..734fba6bc 100644
--- a/types/compilation/cfg.interfaces.ts
+++ b/types/compilation/cfg.interfaces.ts
@@ -24,11 +24,13 @@
 
 // TODO(jeremy-rifkin): re-visit all the types here once the back-end is more typescripted
 
+export type EdgeColor = 'red' | 'green' | 'blue' | 'grey';
+
 export type EdgeDescriptor = {
     from: string;
     to: string;
     arrows: string; // <- useless
-    color: string;
+    color: EdgeColor;
 };
 
 export type NodeDescriptor = {
diff --git a/types/compilation/compilation.interfaces.ts b/types/compilation/compilation.interfaces.ts
index e695ce851..b675f7ceb 100644
--- a/types/compilation/compilation.interfaces.ts
+++ b/types/compilation/compilation.interfaces.ts
@@ -145,6 +145,11 @@ export type CompilationRequest = {
     bypassCache?: BypassCache;
 };
 
+export type PPOutput = {
+    numberOfLinesFiltered: number;
+    output: string;
+};
+
 export type CompilationResult = {
     code: number;
     timedOut: boolean;
@@ -167,14 +172,11 @@ export type CompilationResult = {
     dirPath?: string;
     compilationOptions?: string[];
     downloads?: BuildEnvDownloadInfo[];
-    gccDumpOutput?: any;
+    gccDumpOutput?;
     languageId?: string;
     result?: CompilationResult; // cmake inner result
 
-    ppOutput?: {
-        numberOfLinesFiltered: number;
-        output: string;
-    };
+    ppOutput?: PPOutput;
 
     optOutput?: OptCodeEntry[];
     optPath?: string;
diff --git a/types/compiler.interfaces.ts b/types/compiler.interfaces.ts
index 4bc5a3a0b..6765bad38 100644
--- a/types/compiler.interfaces.ts
+++ b/types/compiler.interfaces.ts
@@ -38,6 +38,12 @@ import {Language, LanguageKey} from './languages.interfaces.js';
 import {Library} from './libraries/libraries.interfaces.js';
 import {Tool, ToolInfo} from './tool.interfaces.js';
 
+export type Remote = {
+    target: string;
+    path: string;
+    cmakePath: string;
+};
+
 export type CompilerInfo = {
     id: string;
     exe: string;
@@ -130,11 +136,7 @@ export type CompilerInfo = {
         preamble?: string;
         invasive?: boolean;
     };
-    remote?: {
-        target: string;
-        path: string;
-        cmakePath: string;
-    };
+    remote?: Remote;
     possibleOverrides?: AllCompilerOverrideOptions;
     possibleRuntimeTools?: PossibleRuntimeTools;
     disabledFilters: string[];