diff --git a/apps/rxjs.dev/tools/marbles/scripts/index.ts b/apps/rxjs.dev/tools/marbles/scripts/index.ts
index 7a32406579..96fda2e2a3 100644
--- a/apps/rxjs.dev/tools/marbles/scripts/index.ts
+++ b/apps/rxjs.dev/tools/marbles/scripts/index.ts
@@ -38,4 +38,4 @@ readdir(diagramsPath, (err, files) => {
     Promise.all(files.map(fileName => renderMarble(diagramsPath, fileName)))
         .then(_ => console.log('All SVGs created'))
         .catch(e => console.error('generating SVGs failed', e));
-});
\ No newline at end of file
+});
diff --git a/apps/rxjs.dev/tools/transforms/angular-base-package/services/filterFromInImports.ts b/apps/rxjs.dev/tools/transforms/angular-base-package/services/filterFromInImports.ts
index 00119016fe..43c8f846de 100644
--- a/apps/rxjs.dev/tools/transforms/angular-base-package/services/filterFromInImports.ts
+++ b/apps/rxjs.dev/tools/transforms/angular-base-package/services/filterFromInImports.ts
@@ -11,7 +11,7 @@
  * unfiltered, thus it will get the link to
  * /api/index/function/from
  */
-module.exports = function filterFromInImports(): (words: string[], index: number) => boolean {
+function filterFromInImports(): (words: string[], index: number) => boolean {
   return (words: string[], index: number) => {
     const previousWord = words[index - 1];
     const nextWord = words[index + 1];
@@ -19,3 +19,5 @@ module.exports = function filterFromInImports(): (words: string[], index: number
     return words[index] === 'from' && /}/.test(previousWord) && /'/.test(nextWord);
   };
 };
+
+export = filterFromInImports
diff --git a/apps/rxjs.dev/tsconfig.json b/apps/rxjs.dev/tsconfig.json
index 8a45002ade..a012968a3d 100644
--- a/apps/rxjs.dev/tsconfig.json
+++ b/apps/rxjs.dev/tsconfig.json
@@ -6,6 +6,7 @@
     "outDir": "./out-tsc",
     "forceConsistentCasingInFileNames": true,
     "strict": true,
+    "isolatedModules": true,
     "noImplicitOverride": true,
     // NOTE: Intentionally deviate from default Angular CLI settings
     //       (due to many violations and uglier syntax).
@@ -45,4 +46,4 @@
     "strictInputAccessModifiers": true,
     "strictTemplates": true
   }
-}
\ No newline at end of file
+}
diff --git a/packages/observable/src/observable.ts b/packages/observable/src/observable.ts
index 31f8403d15..9530f10302 100644
--- a/packages/observable/src/observable.ts
+++ b/packages/observable/src/observable.ts
@@ -351,7 +351,7 @@ export class Subscriber<T> extends Subscription implements Observer<T> {
     }
   }
 
-  unsubscribe(): void {
+  override unsubscribe(): void {
     if (!this.closed) {
       this.isStopped = true;
       super.unsubscribe();
diff --git a/packages/observable/tsconfig.json b/packages/observable/tsconfig.json
index 7f39495db7..6049677818 100644
--- a/packages/observable/tsconfig.json
+++ b/packages/observable/tsconfig.json
@@ -6,6 +6,16 @@
     "forceConsistentCasingInFileNames": true,
     "inlineSources": true,
     "jsx": "react",
+    "exactOptionalPropertyTypes": false,
+    "isolatedModules": true,
+    "noFallthroughCasesInSwitch": true,
+    "noImplicitOverride": true,
+    "noImplicitReturns": true,
+    "noPropertyAccessFromIndexSignature": true,
+    "noUncheckedIndexedAccess": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": false,
+    "noImplicitReturns": true,
     "module": "nodenext",
     "moduleResolution": "nodenext",
     "noUncheckedIndexedAccess": true,
diff --git a/packages/rxjs/package.json b/packages/rxjs/package.json
index 90c26e6051..dcb9b01f9e 100644
--- a/packages/rxjs/package.json
+++ b/packages/rxjs/package.json
@@ -128,7 +128,7 @@
     "@types/chai": "^4.2.11",
     "@types/lodash": "^4.14.198",
     "@types/mocha": "^10.0.1",
-    "@types/node": "^14.14.6",
+    "@types/node": "^24.9.1",
     "@types/shelljs": "^0.8.8",
     "@types/sinon": "^10.0.13",
     "@types/sinon-chai": "^3.2.9",
diff --git a/packages/rxjs/spec/helpers/setup.ts b/packages/rxjs/spec/helpers/setup.ts
index c38b100b77..39cc7e68a1 100644
--- a/packages/rxjs/spec/helpers/setup.ts
+++ b/packages/rxjs/spec/helpers/setup.ts
@@ -3,7 +3,7 @@
  **/
 
 import * as chai from 'chai';
-import * as sinonChai from 'sinon-chai';
+import sinonChai from 'sinon-chai';
 
 if (typeof Symbol !== 'function') {
   let id = 0;
diff --git a/packages/rxjs/spec/operators/groupBy-spec.ts b/packages/rxjs/spec/operators/groupBy-spec.ts
index 51fabbca66..61b4de01f5 100644
--- a/packages/rxjs/spec/operators/groupBy-spec.ts
+++ b/packages/rxjs/spec/operators/groupBy-spec.ts
@@ -1459,8 +1459,8 @@ describe('groupBy operator', () => {
       // Just to get the test going.
       expectObservable(result, unsub).toBe('-');
       // Our two groups should error immediately upon subscription.
-      expectObservable(subjects.a).toBe('-');
-      expectObservable(subjects.b).toBe('-');
+      expectObservable(subjects['a']).toBe('-');
+      expectObservable(subjects['b']).toBe('-');
     });
   });
 
diff --git a/packages/rxjs/spec/tsconfig.json b/packages/rxjs/spec/tsconfig.json
index 4877802e0f..d323060967 100644
--- a/packages/rxjs/spec/tsconfig.json
+++ b/packages/rxjs/spec/tsconfig.json
@@ -2,6 +2,7 @@
   "extends": "../tsconfig.json",
   "compilerOptions": {
     "outDir": "../dist/spec",
+    "moduleResolution": "node10",
     "module": "CommonJS"
   },
   "references": [
@@ -9,4 +10,4 @@
       "path": "../src/tsconfig.types.spec.json"
     }
   ]
-}
\ No newline at end of file
+}
diff --git a/packages/rxjs/src/internal/AsyncSubject.ts b/packages/rxjs/src/internal/AsyncSubject.ts
index e55bb32684..5bde0a266d 100644
--- a/packages/rxjs/src/internal/AsyncSubject.ts
+++ b/packages/rxjs/src/internal/AsyncSubject.ts
@@ -11,7 +11,7 @@ export class AsyncSubject<T> extends Subject<T> {
   private _isComplete = false;
 
   /** @internal */
-  protected _checkFinalizedStatuses(subscriber: Subscriber<T>) {
+  protected override _checkFinalizedStatuses(subscriber: Subscriber<T>) {
     const { hasError, _hasValue, _value, thrownError, _closed, _isComplete } = this;
     if (hasError) {
       subscriber.error(thrownError);
@@ -21,14 +21,14 @@ export class AsyncSubject<T> extends Subject<T> {
     }
   }
 
-  next(value: T): void {
+  override next(value: T): void {
     if (!this._closed) {
       this._value = value;
       this._hasValue = true;
     }
   }
 
-  complete(): void {
+  override complete(): void {
     const { _hasValue, _value, _isComplete } = this;
     if (!_isComplete) {
       this._isComplete = true;
diff --git a/packages/rxjs/src/internal/BehaviorSubject.ts b/packages/rxjs/src/internal/BehaviorSubject.ts
index 54665de436..8ee0a75207 100644
--- a/packages/rxjs/src/internal/BehaviorSubject.ts
+++ b/packages/rxjs/src/internal/BehaviorSubject.ts
@@ -15,7 +15,7 @@ export class BehaviorSubject<T> extends Subject<T> {
   }
 
   /** @internal */
-  protected _subscribe(subscriber: Subscriber<T>): Subscription {
+  protected override _subscribe(subscriber: Subscriber<T>): Subscription {
     const subscription = super._subscribe(subscriber);
     !subscription.closed && subscriber.next(this._value);
     return subscription;
@@ -29,7 +29,7 @@ export class BehaviorSubject<T> extends Subject<T> {
     return _value;
   }
 
-  next(value: T): void {
+  override next(value: T): void {
     super.next((this._value = value));
   }
 }
diff --git a/packages/rxjs/src/internal/ReplaySubject.ts b/packages/rxjs/src/internal/ReplaySubject.ts
index 5bf4d08edf..8347066964 100644
--- a/packages/rxjs/src/internal/ReplaySubject.ts
+++ b/packages/rxjs/src/internal/ReplaySubject.ts
@@ -54,7 +54,7 @@ export class ReplaySubject<T> extends Subject<T> {
     this._windowTime = Math.max(1, _windowTime);
   }
 
-  next(value: T): void {
+  override next(value: T): void {
     const { _closed, _buffer, _infiniteTimeWindow, _timestampProvider, _windowTime } = this;
     if (!_closed) {
       _buffer.push(value);
@@ -65,7 +65,7 @@ export class ReplaySubject<T> extends Subject<T> {
   }
 
   /** @internal */
-  protected _subscribe(subscriber: Subscriber<T>): Subscription {
+  protected override _subscribe(subscriber: Subscriber<T>): Subscription {
     this._trimBuffer();
 
     const subscription = this._innerSubscribe(subscriber);
diff --git a/packages/rxjs/src/internal/Subject.ts b/packages/rxjs/src/internal/Subject.ts
index 0d82bf04e5..14f6700ad8 100644
--- a/packages/rxjs/src/internal/Subject.ts
+++ b/packages/rxjs/src/internal/Subject.ts
@@ -96,7 +96,7 @@ export class Subject<T> extends Observable<T> implements SubscriptionLike {
   }
 
   /** @internal */
-  protected _subscribe(subscriber: Subscriber<T>): Subscription {
+  protected override _subscribe(subscriber: Subscriber<T>): Subscription {
     this._checkFinalizedStatuses(subscriber);
     return this._innerSubscribe(subscriber);
   }
diff --git a/packages/rxjs/src/internal/observable/dom/WebSocketSubject.ts b/packages/rxjs/src/internal/observable/dom/WebSocketSubject.ts
index 943e22a51e..fd5b159f59 100644
--- a/packages/rxjs/src/internal/observable/dom/WebSocketSubject.ts
+++ b/packages/rxjs/src/internal/observable/dom/WebSocketSubject.ts
@@ -365,7 +365,7 @@ export class WebSocketSubject<In, Out = In> extends Observable<Out> {
   }
 
   /** @internal */
-  protected _subscribe(subscriber: Subscriber<Out>): Subscription {
+  protected override _subscribe(subscriber: Subscriber<Out>): Subscription {
     if (!this._socket) {
       this._connectSocket();
     }
diff --git a/packages/rxjs/src/internal/scheduler/AnimationFrameAction.ts b/packages/rxjs/src/internal/scheduler/AnimationFrameAction.ts
index e292df0344..741a5ad590 100644
--- a/packages/rxjs/src/internal/scheduler/AnimationFrameAction.ts
+++ b/packages/rxjs/src/internal/scheduler/AnimationFrameAction.ts
@@ -5,11 +5,11 @@ import { animationFrameProvider } from './animationFrameProvider.js';
 import type { TimerHandle } from './timerHandle.js';
 
 export class AnimationFrameAction<T> extends AsyncAction<T> {
-  constructor(protected scheduler: AnimationFrameScheduler, protected work: (this: SchedulerAction<T>, state?: T) => void) {
+  constructor(protected override scheduler: AnimationFrameScheduler, protected override work: (this: SchedulerAction<T>, state?: T) => void) {
     super(scheduler, work);
   }
 
-  protected requestAsyncId(scheduler: AnimationFrameScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
+  protected override requestAsyncId(scheduler: AnimationFrameScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
     // If delay is greater than 0, request as an async action.
     if (delay !== null && delay > 0) {
       return super.requestAsyncId(scheduler, id, delay);
@@ -22,7 +22,7 @@ export class AnimationFrameAction<T> extends AsyncAction<T> {
     return scheduler._scheduled || (scheduler._scheduled = animationFrameProvider.requestAnimationFrame(() => scheduler.flush(undefined)));
   }
 
-  protected recycleAsyncId(scheduler: AnimationFrameScheduler, id?: TimerHandle, delay: number = 0): TimerHandle | undefined {
+  protected override recycleAsyncId(scheduler: AnimationFrameScheduler, id?: TimerHandle, delay: number = 0): TimerHandle | undefined {
     // If delay exists and is greater than 0, or if the delay is null (the
     // action wasn't rescheduled) but was originally scheduled as an async
     // action, then recycle as an async action.
diff --git a/packages/rxjs/src/internal/scheduler/AnimationFrameScheduler.ts b/packages/rxjs/src/internal/scheduler/AnimationFrameScheduler.ts
index 591466450f..af330d2bc5 100644
--- a/packages/rxjs/src/internal/scheduler/AnimationFrameScheduler.ts
+++ b/packages/rxjs/src/internal/scheduler/AnimationFrameScheduler.ts
@@ -2,7 +2,7 @@ import type { AsyncAction } from './AsyncAction.js';
 import { AsyncScheduler } from './AsyncScheduler.js';
 
 export class AnimationFrameScheduler extends AsyncScheduler {
-  public flush(action?: AsyncAction<any>): void {
+  public override flush(action?: AsyncAction<any>): void {
     this._active = true;
     // The async id that effects a call to flush is stored in _scheduled.
     // Before executing an action, it's necessary to check the action's async
diff --git a/packages/rxjs/src/internal/scheduler/AsapAction.ts b/packages/rxjs/src/internal/scheduler/AsapAction.ts
index e09a470345..4c769f2e83 100644
--- a/packages/rxjs/src/internal/scheduler/AsapAction.ts
+++ b/packages/rxjs/src/internal/scheduler/AsapAction.ts
@@ -5,11 +5,11 @@ import { immediateProvider } from './immediateProvider.js';
 import type { TimerHandle } from './timerHandle.js';
 
 export class AsapAction<T> extends AsyncAction<T> {
-  constructor(protected scheduler: AsapScheduler, protected work: (this: SchedulerAction<T>, state?: T) => void) {
+  constructor(protected override scheduler: AsapScheduler, protected override work: (this: SchedulerAction<T>, state?: T) => void) {
     super(scheduler, work);
   }
 
-  protected requestAsyncId(scheduler: AsapScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
+  protected override requestAsyncId(scheduler: AsapScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
     // If delay is greater than 0, request as an async action.
     if (delay !== null && delay > 0) {
       return super.requestAsyncId(scheduler, id, delay);
@@ -22,7 +22,7 @@ export class AsapAction<T> extends AsyncAction<T> {
     return scheduler._scheduled || (scheduler._scheduled = immediateProvider.setImmediate(scheduler.flush.bind(scheduler, undefined)));
   }
 
-  protected recycleAsyncId(scheduler: AsapScheduler, id?: TimerHandle, delay: number = 0): TimerHandle | undefined {
+  protected override recycleAsyncId(scheduler: AsapScheduler, id?: TimerHandle, delay: number = 0): TimerHandle | undefined {
     // If delay exists and is greater than 0, or if the delay is null (the
     // action wasn't rescheduled) but was originally scheduled as an async
     // action, then recycle as an async action.
diff --git a/packages/rxjs/src/internal/scheduler/AsapScheduler.ts b/packages/rxjs/src/internal/scheduler/AsapScheduler.ts
index 15ac2ed116..4e80780d4d 100644
--- a/packages/rxjs/src/internal/scheduler/AsapScheduler.ts
+++ b/packages/rxjs/src/internal/scheduler/AsapScheduler.ts
@@ -2,7 +2,7 @@ import type { AsyncAction } from './AsyncAction.js';
 import { AsyncScheduler } from './AsyncScheduler.js';
 
 export class AsapScheduler extends AsyncScheduler {
-  public flush(action?: AsyncAction<any>): void {
+  public override flush(action?: AsyncAction<any>): void {
     this._active = true;
     // The async id that effects a call to flush is stored in _scheduled.
     // Before executing an action, it's necessary to check the action's async
diff --git a/packages/rxjs/src/internal/scheduler/AsyncAction.ts b/packages/rxjs/src/internal/scheduler/AsyncAction.ts
index d3acbbba6e..d658616888 100644
--- a/packages/rxjs/src/internal/scheduler/AsyncAction.ts
+++ b/packages/rxjs/src/internal/scheduler/AsyncAction.ts
@@ -16,7 +16,7 @@ export class AsyncAction<T> extends Action<T> {
     super(scheduler, work);
   }
 
-  public schedule(state?: T, delay: number = 0): Subscription {
+  public override schedule(state?: T, delay: number = 0): Subscription {
     if (this.closed) {
       return this;
     }
@@ -129,7 +129,7 @@ export class AsyncAction<T> extends Action<T> {
     }
   }
 
-  unsubscribe() {
+  override unsubscribe() {
     if (!this.closed) {
       const { id, scheduler } = this;
       const { actions } = scheduler;
diff --git a/packages/rxjs/src/internal/scheduler/QueueAction.ts b/packages/rxjs/src/internal/scheduler/QueueAction.ts
index 5f43fc3bd0..c38b7e67dd 100644
--- a/packages/rxjs/src/internal/scheduler/QueueAction.ts
+++ b/packages/rxjs/src/internal/scheduler/QueueAction.ts
@@ -5,11 +5,11 @@ import type { SchedulerAction } from '../types.js';
 import type { TimerHandle } from './timerHandle.js';
 
 export class QueueAction<T> extends AsyncAction<T> {
-  constructor(protected scheduler: QueueScheduler, protected work: (this: SchedulerAction<T>, state?: T) => void) {
+  constructor(protected override scheduler: QueueScheduler, protected override work: (this: SchedulerAction<T>, state?: T) => void) {
     super(scheduler, work);
   }
 
-  public schedule(state?: T, delay: number = 0): Subscription {
+  public override schedule(state?: T, delay: number = 0): Subscription {
     if (delay > 0) {
       return super.schedule(state, delay);
     }
@@ -19,11 +19,11 @@ export class QueueAction<T> extends AsyncAction<T> {
     return this;
   }
 
-  public execute(state: T, delay: number): any {
+  public override execute(state: T, delay: number): any {
     return delay > 0 || this.closed ? super.execute(state, delay) : this._execute(state, delay);
   }
 
-  protected requestAsyncId(scheduler: QueueScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
+  protected override requestAsyncId(scheduler: QueueScheduler, id?: TimerHandle, delay: number = 0): TimerHandle {
     // If delay exists and is greater than 0, or if the delay is null (the
     // action wasn't rescheduled) but was originally scheduled as an async
     // action, then recycle as an async action.
diff --git a/packages/rxjs/src/internal/scheduler/VirtualTimeScheduler.ts b/packages/rxjs/src/internal/scheduler/VirtualTimeScheduler.ts
index efd478342d..642412f623 100644
--- a/packages/rxjs/src/internal/scheduler/VirtualTimeScheduler.ts
+++ b/packages/rxjs/src/internal/scheduler/VirtualTimeScheduler.ts
@@ -37,7 +37,7 @@ export class VirtualTimeScheduler extends AsyncScheduler {
    * Prompt the Scheduler to execute all of its queued actions, therefore
    * clearing its queue.
    */
-  public flush(): void {
+  public override flush(): void {
     const { actions, maxFrames } = this;
     let error: any;
     let action: AsyncAction<any> | undefined;
@@ -64,15 +64,15 @@ export class VirtualAction<T> extends AsyncAction<T> {
   protected active: boolean = true;
 
   constructor(
-    protected scheduler: VirtualTimeScheduler,
-    protected work: (this: SchedulerAction<T>, state?: T) => void,
+    protected override scheduler: VirtualTimeScheduler,
+    protected override work: (this: SchedulerAction<T>, state?: T) => void,
     protected index: number = (scheduler.index += 1)
   ) {
     super(scheduler, work);
     this.index = scheduler.index = index;
   }
 
-  public schedule(state?: T, delay: number = 0): Subscription {
+  public override schedule(state?: T, delay: number = 0): Subscription {
     if (Number.isFinite(delay)) {
       if (!this.id) {
         return super.schedule(state, delay);
@@ -92,7 +92,7 @@ export class VirtualAction<T> extends AsyncAction<T> {
     }
   }
 
-  protected requestAsyncId(scheduler: VirtualTimeScheduler, id?: any, delay: number = 0): TimerHandle {
+  protected override requestAsyncId(scheduler: VirtualTimeScheduler, id?: any, delay: number = 0): TimerHandle {
     this.delay = scheduler.frame + delay;
     const { actions } = scheduler;
     actions.push(this);
@@ -100,11 +100,11 @@ export class VirtualAction<T> extends AsyncAction<T> {
     return 1;
   }
 
-  protected recycleAsyncId(scheduler: VirtualTimeScheduler, id?: any, delay: number = 0): TimerHandle | undefined {
+  protected override recycleAsyncId(scheduler: VirtualTimeScheduler, id?: any, delay: number = 0): TimerHandle | undefined {
     return undefined;
   }
 
-  protected _execute(state: T, delay: number): any {
+  protected override _execute(state: T, delay: number): any {
     if (this.active === true) {
       return super._execute(state, delay);
     }
diff --git a/packages/rxjs/src/internal/testing/ColdObservable.ts b/packages/rxjs/src/internal/testing/ColdObservable.ts
index 53a46aa693..3e97b5566d 100644
--- a/packages/rxjs/src/internal/testing/ColdObservable.ts
+++ b/packages/rxjs/src/internal/testing/ColdObservable.ts
@@ -11,7 +11,7 @@ export class ColdObservable<T> extends Observable<T> {
   logSubscribedFrame = logSubscribedFrame;
   logUnsubscribedFrame = logUnsubscribedFrame;
 
-  protected _subscribe(subscriber: Subscriber<any>): TeardownLogic {
+  protected override _subscribe(subscriber: Subscriber<any>): TeardownLogic {
     const index = this.logSubscribedFrame();
     const subscription = new Subscription();
     subscription.add(
diff --git a/packages/rxjs/src/internal/testing/HotObservable.ts b/packages/rxjs/src/internal/testing/HotObservable.ts
index 162e23bbd3..d205a2d033 100644
--- a/packages/rxjs/src/internal/testing/HotObservable.ts
+++ b/packages/rxjs/src/internal/testing/HotObservable.ts
@@ -19,7 +19,7 @@ export class HotObservable<T> extends Subject<T> {
   }
 
   /** @internal */
-  protected _subscribe(subscriber: Subscriber<any>): Subscription {
+  protected override _subscribe(subscriber: Subscriber<any>): Subscription {
     const index = this.logSubscribedFrame();
     const subscription = new Subscription();
     subscription.add(
diff --git a/packages/rxjs/src/internal/testing/TestScheduler.ts b/packages/rxjs/src/internal/testing/TestScheduler.ts
index 092bd15cb0..17ae40e60d 100644
--- a/packages/rxjs/src/internal/testing/TestScheduler.ts
+++ b/packages/rxjs/src/internal/testing/TestScheduler.ts
@@ -41,7 +41,7 @@ export class TestScheduler extends VirtualTimeScheduler {
    * the test scheduler is being used in "run mode", via the `run` method, this is temporarily
    * set to `1` for the duration of the `run` block, then set back to whatever value it was.
    */
-  static frameTimeFactor = 10;
+  static override frameTimeFactor = 10;
 
   /**
    * @deprecated Internal implementation detail, do not use directly. Will be made internal in v8.
@@ -206,7 +206,7 @@ export class TestScheduler extends VirtualTimeScheduler {
     };
   }
 
-  flush() {
+  override flush() {
     const hotObservables = this.hotObservables;
     while (hotObservables.length > 0) {
       hotObservables.shift()!.setup();
diff --git a/packages/rxjs/src/tsconfig.cjs.json b/packages/rxjs/src/tsconfig.cjs.json
index 89c7a399f8..94553096d9 100644
--- a/packages/rxjs/src/tsconfig.cjs.json
+++ b/packages/rxjs/src/tsconfig.cjs.json
@@ -1,7 +1,6 @@
 {
   "extends": "./tsconfig.base.json",
   "compilerOptions": {
-    "module": "commonjs",
     "target": "ES2022",
     "downlevelIteration": true,
     "outDir": "../dist/cjs"
diff --git a/packages/rxjs/src/tsconfig.esm.json b/packages/rxjs/src/tsconfig.esm.json
index fccb08227c..52f23f90b3 100644
--- a/packages/rxjs/src/tsconfig.esm.json
+++ b/packages/rxjs/src/tsconfig.esm.json
@@ -2,6 +2,7 @@
   "extends": "./tsconfig.base.json",
   "compilerOptions": {
     "module": "esnext",
+    "moduleResolution": "node10",
     "target": "ES2022",
     "outDir": "../dist/esm"
   }
diff --git a/packages/rxjs/src/tsconfig.types.json b/packages/rxjs/src/tsconfig.types.json
index 58312d0cfd..1d0da0f136 100644
--- a/packages/rxjs/src/tsconfig.types.json
+++ b/packages/rxjs/src/tsconfig.types.json
@@ -3,6 +3,7 @@
   "compilerOptions": {
     "composite": true,
     "module": "es2015",
+    "moduleResolution": "node10",
     "target": "ES2022",
     "removeComments": false,
     "declaration": true,
diff --git a/packages/rxjs/tsconfig.json b/packages/rxjs/tsconfig.json
index 691cab447c..809ca0ef5a 100644
--- a/packages/rxjs/tsconfig.json
+++ b/packages/rxjs/tsconfig.json
@@ -1,19 +1,29 @@
 {
   "compilerOptions": {
+    "esModuleInterop": true,
     "incremental": true,
     "removeComments": true,
     "preserveConstEnums": true,
     "sourceMap": true,
     "strict": true,
+    "exactOptionalPropertyTypes": false,
+    "isolatedModules": true,
+    "noFallthroughCasesInSwitch": true,
+    "noImplicitOverride": true,
     "noImplicitReturns": true,
-    "moduleResolution": "node",
+    "noPropertyAccessFromIndexSignature": true,
+    "noUncheckedIndexedAccess": false,
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "module": "node16",
+    "moduleResolution": "node16",
     "stripInternal": true,
     "noEmit": true,
     "lib": ["esnext", "dom"],
     "target": "esnext",
     "baseUrl": ".",
     "paths": {
-      "@rxjs/observable": ["../observable/src/index"],
+      "@rxjs/observable": ["../observable/"],
       "rxjs": ["./src/index"],
       "rxjs/operators": ["./src/operators/index"],
       "rxjs/testing": ["./src/testing/index"],
diff --git a/yarn.lock b/yarn.lock
index 32e4e642ec..5b8c4e1636 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3118,11 +3118,6 @@
   dependencies:
     undici-types "~5.26.4"
 
-"@types/node@^14.14.6":
-  version "14.18.63"
-  resolved "https://registry.yarnpkg.com/@types/node/-/node-14.18.63.tgz#1788fa8da838dbb5f9ea994b834278205db6ca2b"
-  integrity sha512-fAtCfv4jJg+ExtXhvCkCqUKZ+4ok/JQk01qDKhL5BDDoS3AxKXhV5/MAVUZyQnSEd2GT92fkgZl0pz0Q0AzcIQ==
-
 "@types/node@^20.11.0":
   version "20.11.0"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-20.11.0.tgz#8e0b99e70c0c1ade1a86c4a282f7b7ef87c9552f"
@@ -3130,6 +3125,13 @@
   dependencies:
     undici-types "~5.26.4"
 
+"@types/node@^24.9.1":
+  version "24.9.1"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-24.9.1.tgz#b7360b3c789089e57e192695a855aa4f6981a53c"
+  integrity sha512-QoiaXANRkSXK6p0Duvt56W208du4P9Uye9hWLWgGMDTEoKPhuenzNcC4vGUmrNkiOKTlIrBoyNQYNpSwfEZXSg==
+  dependencies:
+    undici-types "~7.16.0"
+
 "@types/parse-json@^4.0.0":
   version "4.0.2"
   resolved "https://registry.yarnpkg.com/@types/parse-json/-/parse-json-4.0.2.tgz#5950e50960793055845e956c427fc2b0d70c5239"
@@ -16546,6 +16548,11 @@ undici-types@~5.26.4:
   resolved "https://registry.yarnpkg.com/undici-types/-/undici-types-5.26.5.tgz#bcd539893d00b56e964fd2657a4866b221a65617"
   integrity sha512-JlCMO+ehdEIKqlFxk6IfVoAUVmgz7cU7zD/h9XZ0qzeosSHmUJVOzSQvvYSYWXkFXC+IfLKSIffhv0sVZup6pA==
 
+undici-types@~7.16.0:
+  version "7.16.0"
+  resolved "https://registry.yarnpkg.com/undici-types/-/undici-types-7.16.0.tgz#ffccdff36aea4884cbfce9a750a0580224f58a46"
+  integrity sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw==
+
 unherit@^1.0.4:
   version "1.1.3"
   resolved "https://registry.yarnpkg.com/unherit/-/unherit-1.1.3.tgz#6c9b503f2b41b262330c80e91c8614abdaa69c22"