diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 20588da37..18d70d0e8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -159,6 +159,7 @@ This project uses [oxlint](https://oxc.rs/docs/guide/usage/linter) and [oxfmt](h
 - Use single quotes for strings
 - Add trailing commas in multiline structures
 - Export types and interfaces alongside implementations
+- Declare private members as `#private` identifiers, and use `protected` only for helpers that subclasses call
 - Avoid `any` types where possible (though the oxlint rule is disabled)
 
 ### Before Committing
@@ -306,6 +307,7 @@ When adding support for a new API resource:
 // src/resource_clients/my_resource.ts
 import { ApiClientSubResourceOptions } from '../base/api_client';
 import { ResourceClient } from '../base/resource_client';
+import * as schemas from '../schemas';
 
 export class MyResourceClient extends ResourceClient {
     constructor(options: ApiClientSubResourceOptions) {
@@ -316,15 +318,15 @@ export class MyResourceClient extends ResourceClient {
     }
 
     async get(): Promise<MyResource | undefined> {
-        return this._get();
+        return this.getResource(schemas.MyResource());
     }
 
     async update(newFields: MyResourceUpdate): Promise<MyResource> {
-        return this._update(newFields);
+        return this.updateResource(schemas.MyResource(), newFields);
     }
 
     async delete(): Promise<void> {
-        return this._delete();
+        return this.deleteResource();
     }
 }
 ```
@@ -335,6 +337,7 @@ export class MyResourceClient extends ResourceClient {
 // src/resource_clients/my_resource_collection.ts
 import { ApiClientSubResourceOptions } from '../base/api_client';
 import { ResourceCollectionClient } from '../base/resource_collection_client';
+import * as schemas from '../schemas';
 import { PaginatedList } from '../utils';
 
 export class MyResourceCollectionClient extends ResourceCollectionClient {
@@ -346,11 +349,11 @@ export class MyResourceCollectionClient extends ResourceCollectionClient {
     }
 
     async list(options?: MyResourceListOptions): Promise<PaginatedList<MyResource>> {
-        return this._list(options);
+        return this.listResources(schemas.ListOfMyResources(), options);
     }
 
     async create(resource: MyResourceCreate): Promise<MyResource> {
-        return this._create(resource);
+        return this.createResource(schemas.MyResource(), resource);
     }
 }
 ```
@@ -360,11 +363,11 @@ export class MyResourceCollectionClient extends ResourceCollectionClient {
 ```typescript
 // In src/apify_client.ts
 myResource(id: string): MyResourceClient {
-    return new MyResourceClient(this._subResourceOptions({ id }));
+    return new MyResourceClient({ id, ...this.subClientOptions() });
 }
 
 myResources(): MyResourceCollectionClient {
-    return new MyResourceCollectionClient(this._options());
+    return new MyResourceCollectionClient(this.subClientOptions());
 }
 ```
 
diff --git a/docs/04_upgrading/upgrading_v3.md b/docs/04_upgrading/upgrading_v3.md
index fd68e85f8..2195ca48e 100644
--- a/docs/04_upgrading/upgrading_v3.md
+++ b/docs/04_upgrading/upgrading_v3.md
@@ -368,3 +368,36 @@ export HTTPS_PROXY=http://proxy.example.com:3128
 ```
 
 The same `proxy-agent` upgrade removes the `[DEP0169] DeprecationWarning` about `url.parse()` that Node.js 24 and newer printed on the client's first request.
+
+## Non-public members no longer carry an underscore
+
+Members declared `private` or `protected` had a leading underscore on top of the keyword in v2, and the underscore is gone in v3. Code that calls only the public methods of a client is unaffected. A class that extends one of the client classes and calls a protected helper has to switch to the new name. The base classes below are not exported, so you reach these members by extending a concrete client such as `ActorClient`.
+
+| Class | v2 | v3 |
+| --- | --- | --- |
+| `ApiClient` | `_url()` | `buildUrl()` |
+| `ApiClient` | `_publicUrl()` | `buildPublicUrl()` |
+| `ApiClient` | `_params()` | `buildParams()` |
+| `ApiClient` | `_subResourceOptions()` | `subResourceOptions()` |
+| `ApiClient` | `_toSafeId()` | `toSafeId()` |
+| `ApiClient` | `_listPaginatedFromCallback()` | `listPaginatedFromCallback()` |
+| `ResourceClient` | `_get()` | `getResource()` |
+| `ResourceClient` | `_update()` | `updateResource()` |
+| `ResourceClient` | `_delete()` | `deleteResource()` |
+| `ResourceClient` | `_waitForFinish()` | `waitForJobFinish()` |
+| `ResourceCollectionClient` | `_list()` | `listResources()` |
+| `ResourceCollectionClient` | `_listPaginated()` | `listResourcesPaginated()` |
+| `ResourceCollectionClient` | `_create()` | `createResource()` |
+| `ResourceCollectionClient` | `_getOrCreate()` | `getOrCreateResource()` |
+| `RequestQueueClient` | `_batchAddRequests()` | `addRequestBatch()` |
+| `RequestQueueClient` | `_batchAddRequestsWithRetries()` | `addRequestBatchWithRetries()` |
+
+A helper got a suffix wherever the bare name would collide with a public method of the same class, which is why `_get()` is now `getResource()` and not `get()`.
+
+<ApiLink to="class/LoggerActorRedirect">`LoggerActorRedirect`</ApiLink> keeps `_log()`, since it overrides the method of that name on the `Logger` base class in `@apify/log`.
+
+The `clientMethod` field on <ApiLink to="class/ApifyApiError">`ApifyApiError`</ApiLink> is parsed from the stack trace, and a public method that delegates to one of these helpers is reported under the helper's name. An error from `client.actor(id).get()` says `ActorClient.getResource`, where v2 said `ActorClient.get`. Adjust anything that matches on these values in your logs.
+
+### Private members are private at runtime
+
+Members that v2 declared `private` are declared with a `#` in v3, so the JavaScript runtime enforces the boundary, where v2 relied on the type checker. Code that reached one of them through a cast, such as `(client.httpClient as any).nodeInitPromise`, throws a `TypeError` in v3. They also don't appear when you spread an instance, iterate `Object.keys()` on it, or pass it to `JSON.stringify()`. The `protected` helpers in the table keep the `protected` keyword, so a subclass can call them.
diff --git a/src/apify_api_error.ts b/src/apify_api_error.ts
index 145717faa..b0c3bae0c 100644
--- a/src/apify_api_error.ts
+++ b/src/apify_api_error.ts
@@ -18,23 +18,6 @@ export type { ApifyApiErrorType } from './models.js';
  */
 const CLIENT_METHOD_REGEX = /at( async)? ([A-Za-z]+(Collection)?Client)\.([A-Za-z]+) \(/;
 
-/**
- * A public method that returns the promise of a shared helper without awaiting it leaves only the helper on
- * the stack, so the helper is reported under the method the caller invoked.
- * @private
- */
-const PUBLIC_METHOD_BY_HELPER: Record<string, string> = {
-    getResource: 'get',
-    updateResource: 'update',
-    deleteResource: 'delete',
-    waitForJobFinish: 'waitForFinish',
-    listResources: 'list',
-    createResource: 'create',
-    getOrCreateResource: 'getOrCreate',
-    addRequestBatch: 'batchAddRequests',
-    addRequestBatchWithRetries: 'batchAddRequests',
-};
-
 /**
  * An `ApifyApiError` is thrown for successful HTTP requests that reach the API,
  * but the API responds with an error response. Typically, those are rate limit
@@ -53,8 +36,9 @@ export class ApifyApiError extends Error {
     override name: string;
 
     /**
-     * The invoked resource client and the method. Known issue: Sometimes it displays
-     * as `unknown` because it can't be parsed from a stack trace.
+     * The resource client and the method parsed from the stack trace, such as `ActorClient.getResource`. A public
+     * method that delegates to a shared helper of its class is reported under the helper. The value is `unknown`
+     * when the stack trace cannot be parsed.
      */
     clientMethod: string;
 
@@ -131,17 +115,17 @@ export class ApifyApiError extends Error {
         super(message);
 
         this.name = this.constructor.name;
-        this.clientMethod = this._extractClientAndMethodFromStack();
+        this.clientMethod = this.#extractClientAndMethodFromStack();
         this.statusCode = response.status;
         this.type = type;
         this.attempt = attempt;
         this.httpMethod = response.config?.method;
-        this.path = this._safelyParsePathFromResponse(response);
+        this.path = this.#safelyParsePathFromResponse(response);
 
         const stack = this.stack!;
 
         this.originalStack = stack.slice(stack.indexOf('\n'));
-        this.stack = this._createApiStack();
+        this.stack = this.#createApiStack();
 
         this.data = errorData;
     }
@@ -156,7 +140,7 @@ export class ApifyApiError extends Error {
         return new ErrorClass(response, attempt);
     }
 
-    private _safelyParsePathFromResponse(response: AxiosResponse) {
+    #safelyParsePathFromResponse(response: AxiosResponse) {
         const urlString = response.config?.url;
         let url;
         try {
@@ -167,10 +151,10 @@ export class ApifyApiError extends Error {
         return url.pathname + url.search;
     }
 
-    private _extractClientAndMethodFromStack() {
+    #extractClientAndMethodFromStack() {
         const match = this.stack!.match(CLIENT_METHOD_REGEX);
         if (!match) return 'unknown';
-        return `${match[2]}.${PUBLIC_METHOD_BY_HELPER[match[4]] ?? match[4]}`;
+        return `${match[2]}.${match[4]}`;
     }
 
     /**
@@ -187,7 +171,7 @@ export class ApifyApiError extends Error {
      *   httpMethod: post
      *   path: /v2/actor-tasks/user~my-task/runs
      */
-    private _createApiStack() {
+    #createApiStack() {
         const { name, ...props } = this;
 
         const stack = Object.entries(props)
diff --git a/src/apify_client.ts b/src/apify_client.ts
index 9b3240242..fe1b92842 100644
--- a/src/apify_client.ts
+++ b/src/apify_client.ts
@@ -136,7 +136,7 @@ export class ApifyClient {
         });
     }
 
-    private subClientOptions() {
+    #subClientOptions() {
         return {
             baseUrl: this.baseUrl,
             publicBaseUrl: this.publicBaseUrl,
@@ -154,7 +154,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/acts-get
      */
     actors(): ActorCollectionClient {
-        return new ActorCollectionClient(this.subClientOptions());
+        return new ActorCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -178,7 +178,7 @@ export class ApifyClient {
 
         return new ActorClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -191,7 +191,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/actor-builds-get
      */
     builds(): BuildCollectionClient {
-        return new BuildCollectionClient(this.subClientOptions());
+        return new BuildCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -208,7 +208,7 @@ export class ApifyClient {
 
         return new BuildClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -221,7 +221,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/datasets-get
      */
     datasets(): DatasetCollectionClient {
-        return new DatasetCollectionClient(this.subClientOptions());
+        return new DatasetCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -254,7 +254,7 @@ export class ApifyClient {
 
         return new DatasetClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -267,7 +267,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/key-value-stores-get
      */
     keyValueStores(): KeyValueStoreCollectionClient {
-        return new KeyValueStoreCollectionClient(this.subClientOptions());
+        return new KeyValueStoreCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -294,7 +294,7 @@ export class ApifyClient {
 
         return new KeyValueStoreClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -310,7 +310,7 @@ export class ApifyClient {
 
         return new LogClient({
             id: buildOrRunId,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -323,7 +323,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/request-queues-get
      */
     requestQueues(): RequestQueueCollectionClient {
-        return new RequestQueueCollectionClient(this.subClientOptions());
+        return new RequestQueueCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -353,7 +353,7 @@ export class ApifyClient {
 
         const apiClientOptions = {
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         };
         return new RequestQueueClient(apiClientOptions, parsed);
     }
@@ -368,7 +368,7 @@ export class ApifyClient {
      */
     runs(): RunCollectionClient {
         return new RunCollectionClient({
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
             resourcePath: 'actor-runs',
         });
     }
@@ -397,7 +397,7 @@ export class ApifyClient {
 
         return new RunClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -410,7 +410,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/actor-tasks-get
      */
     tasks(): TaskCollectionClient {
-        return new TaskCollectionClient(this.subClientOptions());
+        return new TaskCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -433,7 +433,7 @@ export class ApifyClient {
 
         return new TaskClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -446,7 +446,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/schedules-get
      */
     schedules(): ScheduleCollectionClient {
-        return new ScheduleCollectionClient(this.subClientOptions());
+        return new ScheduleCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -463,7 +463,7 @@ export class ApifyClient {
 
         return new ScheduleClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -481,7 +481,7 @@ export class ApifyClient {
 
         return new UserClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -494,7 +494,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/webhooks-get
      */
     webhooks(): WebhookCollectionClient {
-        return new WebhookCollectionClient(this.subClientOptions());
+        return new WebhookCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -511,7 +511,7 @@ export class ApifyClient {
 
         return new WebhookClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -524,7 +524,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/webhook-dispatches-get
      */
     webhookDispatches(): WebhookDispatchCollectionClient {
-        return new WebhookDispatchCollectionClient(this.subClientOptions());
+        return new WebhookDispatchCollectionClient(this.#subClientOptions());
     }
 
     /**
@@ -539,7 +539,7 @@ export class ApifyClient {
 
         return new WebhookDispatchClient({
             id,
-            ...this.subClientOptions(),
+            ...this.#subClientOptions(),
         });
     }
 
@@ -552,7 +552,7 @@ export class ApifyClient {
      * @see https://docs.apify.com/api/v2/store-get
      */
     store(): StoreCollectionClient {
-        return new StoreCollectionClient(this.subClientOptions());
+        return new StoreCollectionClient(this.#subClientOptions());
     }
 
     /**
diff --git a/src/http_client.ts b/src/http_client.ts
index b032744ed..bcf2c0e87 100644
--- a/src/http_client.ts
+++ b/src/http_client.ts
@@ -46,9 +46,9 @@ export class HttpClient {
 
     workflowKey?: string;
 
-    private nodeInitPromise?: Promise<void>;
+    #nodeInitPromise?: Promise<void>;
 
-    private userAgentSuffix?: string | string[];
+    #userAgentSuffix?: string | string[];
 
     constructor(options: HttpClientOptions) {
         const { token } = options;
@@ -64,8 +64,7 @@ export class HttpClient {
         this.timeoutMaxMillis = options.timeoutMaxSecs * 1000;
         this.logger = options.logger;
         this.workflowKey = options.workflowKey || process.env[APIFY_ENV_VARS.WORKFLOW_KEY];
-        this.userAgentSuffix = options.userAgentSuffix;
-        this.onRequestRetry = this.onRequestRetry.bind(this);
+        this.#userAgentSuffix = options.userAgentSuffix;
 
         this.axios = axios.create({
             // Disable axios's built-in proxy handling since we're using custom agents
@@ -117,15 +116,15 @@ export class HttpClient {
         responseInterceptors.forEach((i) => this.axios.interceptors.response.use(i as any));
     }
 
-    private async ensureNodeInit(): Promise<void> {
+    async #ensureNodeInit(): Promise<void> {
         if (!isNode()) return;
 
-        this.nodeInitPromise ??= this.initNode();
+        this.#nodeInitPromise ??= this.#initNode();
 
-        return this.nodeInitPromise;
+        return this.#nodeInitPromise;
     }
 
-    private async initNode(): Promise<void> {
+    async #initNode(): Promise<void> {
         if (!isNode()) return;
 
         const [{ ProxyAgent }, os] = await Promise.all([import('proxy-agent'), import('node:os')]);
@@ -173,26 +172,26 @@ export class HttpClient {
         const isAtHome = !!process.env[APIFY_ENV_VARS.IS_AT_HOME];
         let userAgent = `ApifyClient/${version} (${os.platform()}; Node/${process.version}); isAtHome/${isAtHome}`;
 
-        if (this.userAgentSuffix) {
-            userAgent += `; ${asArray(this.userAgentSuffix).join('; ')}`;
+        if (this.#userAgentSuffix) {
+            userAgent += `; ${asArray(this.#userAgentSuffix).join('; ')}`;
         }
 
         this.axios.defaults.headers['User-Agent'] = userAgent;
     }
 
     async call<T = any>(config: ApifyRequestConfig): Promise<ApifyResponse<T>> {
-        await this.ensureNodeInit();
+        await this.#ensureNodeInit();
         this.stats.calls++;
-        const makeRequest = this.createRequestHandler(config);
+        const makeRequest = this.#createRequestHandler(config);
 
         return retry(makeRequest, {
             retries: this.maxRetries,
             minTimeout: this.minDelayBetweenRetriesMillis,
-            onRetry: this.onRequestRetry,
+            onRetry: (error, attempt) => this.#onRequestRetry(error, attempt),
         });
     }
 
-    private informAboutStreamNoRetry() {
+    #informAboutStreamNoRetry() {
         this.logger.warningOnce(
             'Request body was a stream - retrying will not work, as part of it was already consumed.',
         );
@@ -206,7 +205,7 @@ export class HttpClient {
      * status codes are retried. See the following functions for the
      * retrying logic.
      */
-    private createRequestHandler(config: ApifyRequestConfig) {
+    #createRequestHandler(config: ApifyRequestConfig) {
         const { timeoutSecs = 'medium', ...axiosConfig } = config;
 
         const makeRequest: RetryFunction<ApifyResponse, Error> = async (stopTrying, attempt) => {
@@ -224,11 +223,11 @@ export class HttpClient {
 
                 response = await this.axios.request({
                     ...axiosConfig,
-                    timeout: this.computeTimeoutMillis(timeoutSecs, attempt),
+                    timeout: this.#computeTimeoutMillis(timeoutSecs, attempt),
                 });
-                if (this.isStatusOk(response.status)) return response;
+                if (this.#isStatusOk(response.status)) return response;
             } catch (err) {
-                return cast(this.handleRequestError(err as AxiosError, config, stopTrying));
+                return cast(this.#handleRequestError(err as AxiosError, config, stopTrying));
             }
 
             if (response.status === RATE_LIMIT_EXCEEDED_STATUS_CODE) {
@@ -236,9 +235,9 @@ export class HttpClient {
             }
 
             const apiError = ApifyApiError.fromResponse(response, attempt);
-            if (this.isStatusCodeRetryable(response.status)) {
+            if (this.#isStatusCodeRetryable(response.status)) {
                 if (requestIsStream) {
-                    this.informAboutStreamNoRetry();
+                    this.#informAboutStreamNoRetry();
                 } else {
                     // allow a retry
                     throw apiError;
@@ -252,7 +251,7 @@ export class HttpClient {
         return makeRequest;
     }
 
-    private isStatusOk(statusCode: number) {
+    #isStatusOk(statusCode: number) {
         return statusCode < 300;
     }
 
@@ -262,7 +261,7 @@ export class HttpClient {
      * as no timeout. The result doubles with each attempt and is capped at `timeoutMaxMillis`. A requested
      * value above the cap is capped too, which warns once, since it does not take effect in full.
      */
-    private computeTimeoutMillis(timeoutSecs: Timeout, attempt: number): number {
+    #computeTimeoutMillis(timeoutSecs: Timeout, attempt: number): number {
         if (timeoutSecs === 'noTimeout') return 0;
 
         const requestedMillis = typeof timeoutSecs === 'number' ? timeoutSecs * 1000 : this.timeoutMillis[timeoutSecs];
@@ -283,14 +282,14 @@ export class HttpClient {
      * Handles all unexpected errors that can happen, but are not
      * Apify API typed errors. E.g. network errors, timeouts and so on.
      */
-    private handleRequestError(err: AxiosError, config: ApifyRequestConfig, stopTrying: (e: Error) => void) {
-        if (this.isTimeoutError(err) && config.doNotRetryTimeouts) {
+    #handleRequestError(err: AxiosError, config: ApifyRequestConfig, stopTrying: (e: Error) => void) {
+        if (this.#isTimeoutError(err) && config.doNotRetryTimeouts) {
             return stopTrying(err);
         }
 
-        if (this.isRetryableError(err)) {
+        if (this.#isRetryableError(err)) {
             if (isStream(config.data)) {
-                this.informAboutStreamNoRetry();
+                this.#informAboutStreamNoRetry();
             } else {
                 throw err;
             }
@@ -302,7 +301,7 @@ export class HttpClient {
      * Axios calls req.abort() on timeouts so timeout errors will
      * have a code ECONNABORTED.
      */
-    private isTimeoutError(err: AxiosError) {
+    #isTimeoutError(err: AxiosError) {
         return err.code === 'ECONNABORTED';
     }
 
@@ -312,8 +311,8 @@ export class HttpClient {
      * @param {Error} err
      * @private
      */
-    private isRetryableError(err: AxiosError) {
-        return this.isNetworkError(err) || this.isResponseBodyInvalid(err);
+    #isRetryableError(err: AxiosError) {
+        return this.#isNetworkError(err) || this.#isResponseBodyInvalid(err);
     }
 
     /**
@@ -321,7 +320,7 @@ export class HttpClient {
      * a response, the request often does not fail, but simply contains
      * an incomplete response. This can often be fixed by retrying.
      */
-    private isResponseBodyInvalid(err: Error): err is InvalidResponseBodyError {
+    #isResponseBodyInvalid(err: Error): err is InvalidResponseBodyError {
         return err instanceof InvalidResponseBodyError;
     }
 
@@ -330,7 +329,7 @@ export class HttpClient {
      * it throws an AxiosError, which will have the request
      * and config (and other) properties.
      */
-    private isNetworkError(err: AxiosError) {
+    #isNetworkError(err: AxiosError) {
         const hasRequest = err.request && typeof err.request === 'object';
         const hasConfig = err.config && typeof err.config === 'object';
         return hasRequest && hasConfig;
@@ -341,13 +340,13 @@ export class HttpClient {
      * For status codes 300-499 (except 429) we do not retry the request,
      * because it's probably caused by invalid url (redirect 3xx) or invalid user input (4xx).
      */
-    private isStatusCodeRetryable(statusCode: number) {
+    #isStatusCodeRetryable(statusCode: number) {
         const isRateLimitError = statusCode === RATE_LIMIT_EXCEEDED_STATUS_CODE;
         const isInternalError = statusCode >= 500;
         return isRateLimitError || isInternalError;
     }
 
-    private onRequestRetry(error: Error, attempt: number) {
+    #onRequestRetry(error: Error, attempt: number) {
         if (attempt === Math.round(this.maxRetries / 2)) {
             this.logger.warning(
                 `API request failed ${attempt} times. Max attempts: ${this.maxRetries + 1}.\nCause:${error.stack}`,
diff --git a/src/resource_clients/dataset.ts b/src/resource_clients/dataset.ts
index a38121178..c3528afbc 100644
--- a/src/resource_clients/dataset.ts
+++ b/src/resource_clients/dataset.ts
@@ -230,7 +230,7 @@ export class DatasetClient<
                 timeoutSecs,
             });
 
-            return this.createPaginationList(response, datasetListOptions.desc ?? false);
+            return this.#createPaginationList(response, datasetListOptions.desc ?? false);
         };
 
         return this.listPaginatedFromCallback(fetchItems, listOptions);
@@ -435,7 +435,7 @@ export class DatasetClient<
         return createdItemsPublicUrl.toString();
     }
 
-    private createPaginationList(response: ApifyResponse, userProvidedDesc: boolean): PaginatedList<Data> {
+    #createPaginationList(response: ApifyResponse, userProvidedDesc: boolean): PaginatedList<Data> {
         const page: PaginatedList<Data> = {
             items: response.data,
             total: Number(response.headers['x-apify-pagination-total']),
diff --git a/src/resource_clients/log.ts b/src/resource_clients/log.ts
index bb8d1b94a..e523014c0 100644
--- a/src/resource_clients/log.ts
+++ b/src/resource_clients/log.ts
@@ -163,73 +163,73 @@ export class LoggerActorRedirect extends Logger {
  * @since Added in 2.20.0
  */
 export class StreamedLog {
-    private destinationLog: Log;
-    private streamBuffer: Buffer[] = [];
-    private splitMarker = /(?:\n|^)(\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z)/g;
-    private relevancyTimeLimit: Date | null;
+    #destinationLog: Log;
+    #streamBuffer: Buffer[] = [];
+    #splitMarker = /(?:\n|^)(\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z)/g;
+    #relevancyTimeLimit: Date | null;
 
-    private logClient: LogClient;
-    private streamingTask: Promise<void> | null = null;
-    private stopLogging = false;
+    #logClient: LogClient;
+    #streamingTask: Promise<void> | null = null;
+    #stopLogging = false;
 
     constructor(options: StreamedLogOptions) {
         const { toLog, logClient, fromStart = true } = options;
-        this.destinationLog = toLog;
-        this.logClient = logClient;
-        this.relevancyTimeLimit = fromStart ? null : new Date();
+        this.#destinationLog = toLog;
+        this.#logClient = logClient;
+        this.#relevancyTimeLimit = fromStart ? null : new Date();
     }
 
     /**
      * Start log redirection.
      */
     public start(): void {
-        if (this.streamingTask) {
+        if (this.#streamingTask) {
             throw new Error('Streaming task already active');
         }
-        this.stopLogging = false;
-        this.streamingTask = this.streamLog();
+        this.#stopLogging = false;
+        this.#streamingTask = this.#streamLog();
     }
 
     /**
      * Stop log redirection.
      */
     public async stop(): Promise<void> {
-        if (!this.streamingTask) {
+        if (!this.#streamingTask) {
             throw new Error('Streaming task is not active');
         }
-        this.stopLogging = true;
+        this.#stopLogging = true;
         try {
-            await this.streamingTask;
+            await this.#streamingTask;
         } catch (err) {
             if (!(err instanceof Error && err.name === 'AbortError')) {
                 throw err;
             }
         } finally {
-            this.streamingTask = null;
+            this.#streamingTask = null;
         }
     }
 
     /**
      * Get log stream from response and redirect it to another log.
      */
-    private async streamLog(): Promise<void> {
+    async #streamLog(): Promise<void> {
         try {
-            const logStream = await this.logClient.stream({ raw: true });
+            const logStream = await this.#logClient.stream({ raw: true });
             if (!logStream) {
                 return;
             }
-            const lastChunkRemainder = await this.logStreamChunks(logStream);
+            const lastChunkRemainder = await this.#logStreamChunks(logStream);
             // Process whatever is left when exiting. Maybe it is incomplete, maybe it is last log without EOL.
             const lastMessage = Buffer.from(lastChunkRemainder).toString().trim();
             if (lastMessage.length) {
-                this.destinationLog.info(lastMessage);
+                this.#destinationLog.info(lastMessage);
             }
         } catch (err) {
             log.warning(`Log redirection stopped due to error`, err as Error);
         }
     }
 
-    private async logStreamChunks(logStream: Readable): Promise<Uint8Array> {
+    async #logStreamChunks(logStream: Readable): Promise<Uint8Array> {
         // Chunk may be incomplete. Keep remainder for next chunk.
         let previousChunkRemainder: Uint8Array = new Uint8Array();
 
@@ -244,11 +244,11 @@ export class StreamedLog {
             previousChunkRemainder = chunkWithPreviousRemainder.slice(lastCompleteMessageIndex);
 
             // Push complete part of the chunk to the buffer
-            this.streamBuffer.push(Buffer.from(chunkWithPreviousRemainder.slice(0, lastCompleteMessageIndex)));
-            this.logBufferContent();
+            this.#streamBuffer.push(Buffer.from(chunkWithPreviousRemainder.slice(0, lastCompleteMessageIndex)));
+            this.#logBufferContent();
 
             // Keep processing the new data until stopped
-            if (this.stopLogging) {
+            if (this.#stopLogging) {
                 break;
             }
         }
@@ -258,20 +258,20 @@ export class StreamedLog {
     /**
      * Parse the buffer and log complete messages.
      */
-    private logBufferContent(): void {
-        const allParts = Buffer.concat(this.streamBuffer).toString().split(this.splitMarker).slice(1);
+    #logBufferContent(): void {
+        const allParts = Buffer.concat(this.#streamBuffer).toString().split(this.#splitMarker).slice(1);
         // Parse the buffer parts into complete messages
         const messageMarkers = allParts.filter((_, i) => i % 2 === 0);
         const messageContents = allParts.filter((_, i) => i % 2 !== 0);
-        this.streamBuffer = [];
+        this.#streamBuffer = [];
 
         messageMarkers.forEach((marker, index) => {
             const decodedMarker = marker;
             const decodedContent = messageContents[index];
-            if (this.relevancyTimeLimit) {
+            if (this.#relevancyTimeLimit) {
                 // Log only relevant messages. Ignore too old log messages.
                 const logTime = new Date(decodedMarker);
-                if (logTime < this.relevancyTimeLimit) {
+                if (logTime < this.#relevancyTimeLimit) {
                     return;
                 }
             }
@@ -279,7 +279,7 @@ export class StreamedLog {
 
             // Original log level information is not available. Log all on info level. Log level could be guessed for
             // some logs, but for any multiline logs such guess would be probably correct only for the first line.
-            this.destinationLog.info(message.trim());
+            this.#destinationLog.info(message.trim());
         });
     }
 }
diff --git a/src/resource_clients/request_queue.ts b/src/resource_clients/request_queue.ts
index 54e06ac69..78c5f74c9 100644
--- a/src/resource_clients/request_queue.ts
+++ b/src/resource_clients/request_queue.ts
@@ -145,9 +145,9 @@ export type {
  * @see https://docs.apify.com/platform/storage/request-queue
  */
 export class RequestQueueClient extends ResourceClient {
-    private clientKey?: string;
+    #clientKey?: string;
 
-    private timeoutSecs?: number;
+    #timeoutSecs?: number;
 
     /**
      * @hidden
@@ -158,19 +158,19 @@ export class RequestQueueClient extends ResourceClient {
             ...options,
         });
 
-        this.clientKey = userOptions.clientKey;
-        this.timeoutSecs = userOptions.timeoutSecs;
+        this.#clientKey = userOptions.clientKey;
+        this.#timeoutSecs = userOptions.timeoutSecs;
     }
 
     /**
      * Picks the timeout of a request: an explicit per-call `timeoutSecs` as is, otherwise the method's default
      * tier, capped at the queue-wide `timeoutSecs` when one was given.
      */
-    private resolveTimeout(timeoutSecs: Timeout | undefined, defaultTier: TimeoutTier): Timeout {
+    #resolveTimeout(timeoutSecs: Timeout | undefined, defaultTier: TimeoutTier): Timeout {
         if (timeoutSecs !== undefined) return timeoutSecs;
-        if (this.timeoutSecs === undefined) return defaultTier;
+        if (this.#timeoutSecs === undefined) return defaultTier;
         const tierSecs = this.httpClient.timeoutMillis[defaultTier] / 1000;
-        return tierSecs <= this.timeoutSecs ? defaultTier : this.timeoutSecs;
+        return tierSecs <= this.#timeoutSecs ? defaultTier : this.#timeoutSecs;
     }
 
     /**
@@ -184,7 +184,7 @@ export class RequestQueueClient extends ResourceClient {
     async get(options: TimeoutOptions = {}): Promise<RequestQueue | undefined> {
         const { timeoutSecs } = parseArgument(options, timeoutOptionsSchema, 'TimeoutOptions');
 
-        return this.getResource(schemas.RequestQueue(), {}, this.resolveTimeout(timeoutSecs, 'short'));
+        return this.getResource(schemas.RequestQueue(), {}, this.#resolveTimeout(timeoutSecs, 'short'));
     }
 
     /**
@@ -200,7 +200,7 @@ export class RequestQueueClient extends ResourceClient {
         parseArgument(newFields, anyObjectSchema);
         const { timeoutSecs } = parseArgument(options, timeoutOptionsSchema, 'TimeoutOptions');
 
-        return this.updateResource(schemas.RequestQueue(), newFields, this.resolveTimeout(timeoutSecs, 'short'));
+        return this.updateResource(schemas.RequestQueue(), newFields, this.#resolveTimeout(timeoutSecs, 'short'));
     }
 
     /**
@@ -213,7 +213,7 @@ export class RequestQueueClient extends ResourceClient {
     async delete(options: TimeoutOptions = {}): Promise<void> {
         const { timeoutSecs } = parseArgument(options, timeoutOptionsSchema, 'TimeoutOptions');
 
-        return this.deleteResource(this.resolveTimeout(timeoutSecs, 'short'));
+        return this.deleteResource(this.#resolveTimeout(timeoutSecs, 'short'));
     }
 
     /**
@@ -234,10 +234,10 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl('head'),
             method: 'GET',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'short'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'short'),
             params: this.buildParams({
                 limit: parsed.limit,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -286,11 +286,11 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl('head/lock'),
             method: 'POST',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'medium'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'medium'),
             params: this.buildParams({
                 limit: parsed.limit,
                 lockSecs: parsed.lockSecs,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -346,11 +346,11 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl('requests'),
             method: 'POST',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'short'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'short'),
             data: request,
             params: this.buildParams({
                 forefront: parsed.forefront,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -372,11 +372,11 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl('requests/batch'),
             method: 'POST',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'medium'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'medium'),
             data: requests,
             params: this.buildParams({
                 forefront: parsed.forefront,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -575,10 +575,10 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl('requests/batch'),
             method: 'DELETE',
-            timeoutSecs: this.resolveTimeout(timeoutSecs, 'short'),
+            timeoutSecs: this.#resolveTimeout(timeoutSecs, 'short'),
             data: requests,
             params: this.buildParams({
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -604,7 +604,7 @@ export class RequestQueueClient extends ResourceClient {
         const requestOpts: ApifyRequestConfig = {
             url: this.buildUrl(['requests', id]),
             method: 'GET',
-            timeoutSecs: this.resolveTimeout(timeoutSecs, 'short'),
+            timeoutSecs: this.#resolveTimeout(timeoutSecs, 'short'),
             params: this.buildParams(),
         };
         try {
@@ -637,11 +637,11 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl(['requests', request.id]),
             method: 'PUT',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'medium'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'medium'),
             data: request,
             params: this.buildParams({
                 forefront: parsed.forefront,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -662,9 +662,9 @@ export class RequestQueueClient extends ResourceClient {
         await this.httpClient.call({
             url: this.buildUrl(['requests', id]),
             method: 'DELETE',
-            timeoutSecs: this.resolveTimeout(timeoutSecs, 'short'),
+            timeoutSecs: this.#resolveTimeout(timeoutSecs, 'short'),
             params: this.buildParams({
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
     }
@@ -709,11 +709,11 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl(['requests', id, 'lock']),
             method: 'PUT',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'medium'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'medium'),
             params: this.buildParams({
                 forefront: parsed.forefront,
                 lockSecs: parsed.lockSecs,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
@@ -740,10 +740,10 @@ export class RequestQueueClient extends ResourceClient {
         await this.httpClient.call({
             url: this.buildUrl(['requests', id, 'lock']),
             method: 'DELETE',
-            timeoutSecs: this.resolveTimeout(parsed.timeoutSecs, 'short'),
+            timeoutSecs: this.#resolveTimeout(parsed.timeoutSecs, 'short'),
             params: this.buildParams({
                 forefront: parsed.forefront,
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
     }
@@ -769,7 +769,7 @@ export class RequestQueueClient extends ResourceClient {
             listRequestsOptionsSchema,
             'RequestQueueClientListRequestsOptions',
         );
-        const pageTimeout = this.resolveTimeout(timeoutSecs, 'medium');
+        const pageTimeout = this.#resolveTimeout(timeoutSecs, 'medium');
 
         const getPaginatedList = async (
             rqListOptions: RequestQueueClientListRequestsOptions = {},
@@ -781,7 +781,7 @@ export class RequestQueueClient extends ResourceClient {
                 params: this.buildParams({
                     ...rqListOptions,
                     filter: rqListOptions.filter ? rqListOptions.filter.join(',') : undefined,
-                    clientKey: this.clientKey,
+                    clientKey: this.#clientKey,
                 }),
             });
 
@@ -838,9 +838,9 @@ export class RequestQueueClient extends ResourceClient {
         const response = await this.httpClient.call({
             url: this.buildUrl('requests/unlock'),
             method: 'POST',
-            timeoutSecs: this.resolveTimeout(timeoutSecs, 'long'),
+            timeoutSecs: this.#resolveTimeout(timeoutSecs, 'long'),
             params: this.buildParams({
-                clientKey: this.clientKey,
+                clientKey: this.#clientKey,
             }),
         });
 
diff --git a/src/statistics.ts b/src/statistics.ts
index d19923989..d5c7a00c5 100644
--- a/src/statistics.ts
+++ b/src/statistics.ts
@@ -26,7 +26,7 @@ export class Statistics {
         // attempt is never 0,
         // but we don't want index 0 empty
         const index = attempt - 1;
-        this._fillBlanksWithZeroes(index);
+        this.#fillBlanksWithZeroes(index);
         this.rateLimitErrors[index]++;
     }
 
@@ -35,7 +35,7 @@ export class Statistics {
      * number of zeroes by dynamically filling the empty indexes
      * when necessary.
      */
-    private _fillBlanksWithZeroes(inclusiveIndex: number) {
+    #fillBlanksWithZeroes(inclusiveIndex: number) {
         if (this.rateLimitErrors.length <= inclusiveIndex) {
             for (let k = 0; k <= inclusiveIndex; k++) {
                 if (typeof this.rateLimitErrors[k] !== 'number') {
diff --git a/src/utils.ts b/src/utils.ts
index 25e623edb..4b6abdc26 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -374,32 +374,30 @@ export function getVersionData(): { version: string } {
  * Helper class to create async iterators from paginated list endpoints.
  */
 export class RequestQueuePaginationIterator {
-    private readonly maxPageLimit: number;
+    readonly #maxPageLimit: number;
 
-    private readonly getPage: (
-        opts: RequestQueueClientListRequestsOptions,
-    ) => Promise<RequestQueueClientListRequestsResult>;
+    readonly #getPage: (opts: RequestQueueClientListRequestsOptions) => Promise<RequestQueueClientListRequestsResult>;
 
-    private readonly limit?: number;
+    readonly #limit?: number;
 
-    private readonly cursor?: string;
+    readonly #cursor?: string;
 
     constructor(options: RequestQueuePaginationIteratorOptions) {
-        this.maxPageLimit = options.maxPageLimit;
-        this.limit = options.limit;
-        this.cursor = options.cursor;
-        this.getPage = options.getPage;
+        this.#maxPageLimit = options.maxPageLimit;
+        this.#limit = options.limit;
+        this.#cursor = options.cursor;
+        this.#getPage = options.getPage;
     }
 
     async *[Symbol.asyncIterator](): AsyncIterator<RequestQueueClientListRequestsResult> {
-        let nextCursor = this.cursor;
+        let nextCursor = this.#cursor;
         let iterateItemCount = 0;
         while (true) {
-            const pageLimit = this.limit
-                ? Math.min(this.maxPageLimit, this.limit - iterateItemCount)
-                : this.maxPageLimit;
+            const pageLimit = this.#limit
+                ? Math.min(this.#maxPageLimit, this.#limit - iterateItemCount)
+                : this.#maxPageLimit;
 
-            const page: RequestQueueClientListRequestsResult = await this.getPage({
+            const page: RequestQueueClientListRequestsResult = await this.#getPage({
                 limit: pageLimit,
                 cursor: nextCursor,
             });
@@ -408,7 +406,7 @@ export class RequestQueuePaginationIterator {
             yield page;
             iterateItemCount += page.items.length;
             // Limit reached stopping to iterate
-            if ((this.limit && iterateItemCount >= this.limit) || !page.nextCursor) return;
+            if ((this.#limit && iterateItemCount >= this.#limit) || !page.nextCursor) return;
 
             nextCursor = page.nextCursor;
         }
diff --git a/test/apify_api_error.test.ts b/test/apify_api_error.test.ts
index c9e4ba7cd..bbaf85460 100644
--- a/test/apify_api_error.test.ts
+++ b/test/apify_api_error.test.ts
@@ -46,7 +46,8 @@ describe('ApifyApiError', () => {
             // This does not work in v10 and lower, but we want to be able to run tests for v10,
             // because some people might still use it. They will just see clientMethod: undefined.
             if (!process.version.startsWith('v10')) {
-                expect(err.clientMethod).toBe(`${actorCollectionClient.constructor.name}.${method}`);
+                // `list()` returns the promise of the `listResources` helper, so the helper is the frame on the stack.
+                expect(err.clientMethod).toBe(`${actorCollectionClient.constructor.name}.listResources`);
             }
             expect(err.type).toEqual('token-not-provided');
             expect(err.message).toEqual('Authentication token was not provided');
@@ -77,7 +78,7 @@ describe('ApifyApiError', () => {
         }, method);
 
         expect(error.name).toEqual('UnauthorizedError');
-        expect(error.clientMethod).toBe(`ActorCollectionClient.${method}`);
+        expect(error.clientMethod).toBe('ActorCollectionClient.listResources');
         expect(error.type).toEqual('token-not-provided');
         expect(error.message).toEqual('Authentication token was not provided');
         expect(error.statusCode).toEqual(401);