diff --git a/src/internal/Subscriber.ts b/src/internal/Subscriber.ts
index a09986d5c1..e682fe402b 100644
--- a/src/internal/Subscriber.ts
+++ b/src/internal/Subscriber.ts
@@ -203,7 +203,7 @@ export class SafeSubscriber<T> extends Subscriber<T> {
       // The first argument is a function, not an observer. The next
       // two arguments *could* be observers, or they could be empty.
       partialObserver = {
-        next: observerOrNext ?? undefined,
+        next: (observerOrNext ?? undefined) as (((value: T) => void) | undefined),
         error: error ?? undefined,
         complete: complete ?? undefined,
       };
diff --git a/src/internal/operators/groupBy.ts b/src/internal/operators/groupBy.ts
index 33d5b23ddd..4e4d573f86 100644
--- a/src/internal/operators/groupBy.ts
+++ b/src/internal/operators/groupBy.ts
@@ -147,7 +147,7 @@ export function groupBy<T, K, R>(
   return operate((source, subscriber) => {
     let element: ((value: any) => any) | void;
     if (!elementOrOptions || typeof elementOrOptions === 'function') {
-      element = elementOrOptions;
+      element = elementOrOptions as ((value: any) => any);
     } else {
       ({ duration, element, connector } = elementOrOptions);
     }
diff --git a/src/internal/operators/retry.ts b/src/internal/operators/retry.ts
index 74c5f5fc0b..ed04776b55 100644
--- a/src/internal/operators/retry.ts
+++ b/src/internal/operators/retry.ts
@@ -86,7 +86,7 @@ export function retry<T>(configOrCount: number | RetryConfig = Infinity): MonoTy
     config = configOrCount;
   } else {
     config = {
-      count: configOrCount,
+      count: configOrCount as number,
     };
   }
   const { count = Infinity, delay, resetOnSuccess: resetOnSuccess = false } = config;
diff --git a/src/internal/operators/shareReplay.ts b/src/internal/operators/shareReplay.ts
index 095c7df111..28149a6568 100644
--- a/src/internal/operators/shareReplay.ts
+++ b/src/internal/operators/shareReplay.ts
@@ -161,7 +161,7 @@ export function shareReplay<T>(
   if (configOrBufferSize && typeof configOrBufferSize === 'object') {
     ({ bufferSize = Infinity, windowTime = Infinity, refCount = false, scheduler } = configOrBufferSize);
   } else {
-    bufferSize = configOrBufferSize ?? Infinity;
+    bufferSize = (configOrBufferSize ?? Infinity) as number;
   }
   return share<T>({
     connector: () => new ReplaySubject(bufferSize, windowTime, scheduler),
diff --git a/src/internal/scheduler/intervalProvider.ts b/src/internal/scheduler/intervalProvider.ts
index dc64c7c91f..6e06286e46 100644
--- a/src/internal/scheduler/intervalProvider.ts
+++ b/src/internal/scheduler/intervalProvider.ts
@@ -1,4 +1,4 @@
-type SetIntervalFunction = (handler: () => void, timeout?: number, ...args: any[]) => number;
+type SetIntervalFunction = (handler: () => void, timeout?: number, ...args: any[]) => unknown;
 type ClearIntervalFunction = (handle: number) => void;
 
 interface IntervalProvider {
diff --git a/src/internal/scheduler/timeoutProvider.ts b/src/internal/scheduler/timeoutProvider.ts
index 8cee7673e2..4d0c7fea0f 100644
--- a/src/internal/scheduler/timeoutProvider.ts
+++ b/src/internal/scheduler/timeoutProvider.ts
@@ -1,4 +1,4 @@
-type SetTimeoutFunction = (handler: () => void, timeout?: number, ...args: any[]) => number;
+type SetTimeoutFunction = (handler: () => void, timeout?: number, ...args: any[]) => unknown;
 type ClearTimeoutFunction = (handle: number) => void;
 
 interface TimeoutProvider {
diff --git a/src/internal/util/workarounds.ts b/src/internal/util/workarounds.ts
index 7a2ae54b93..00c01b881a 100644
--- a/src/internal/util/workarounds.ts
+++ b/src/internal/util/workarounds.ts
@@ -3,3 +3,5 @@
 // Wherever possible, use a TypeScript issue number in the type - something
 // like TS_18757 - or use a descriptive name and leave a detailed comment
 // alongside the type alias.
+
+export {}