diff --git a/frontend/sync-client/src/file-operations/safe-filesystem-operations.ts b/frontend/sync-client/src/file-operations/safe-filesystem-operations.ts
index e7c1d29..94ee8ad 100644
--- a/frontend/sync-client/src/file-operations/safe-filesystem-operations.ts
+++ b/frontend/sync-client/src/file-operations/safe-filesystem-operations.ts
@@ -2,7 +2,7 @@ import type { FileSystemOperations } from "dist/types";
 import type { RelativePath } from "src/persistence/database";
 
 export class FileNotFoundError extends Error {
-	constructor(message: string) {
+	public constructor(message: string) {
 		super(message);
 		this.name = "FileNotFoundError";
 	}
diff --git a/frontend/sync-client/src/sync-operations/syncer.ts b/frontend/sync-client/src/sync-operations/syncer.ts
index 0c764c3..652d9c5 100644
--- a/frontend/sync-client/src/sync-operations/syncer.ts
+++ b/frontend/sync-client/src/sync-operations/syncer.ts
@@ -95,16 +95,6 @@ export class Syncer {
 		);
 	}
 
-	private async syncRemotelyUpdatedFile(
-		remoteVersion: components["schemas"]["DocumentVersionWithoutContent"]
-	): Promise<void> {
-		await this.syncQueue.add(async () =>
-			this.internalSyncer.unrestrictedSyncRemotelyUpdatedFile(
-				remoteVersion
-			)
-		);
-	}
-
 	public async scheduleSyncForOfflineChanges(): Promise<void> {
 		if (!this.settings.getSettings().isSyncEnabled) {
 			this.logger.debug(
@@ -133,6 +123,52 @@ export class Syncer {
 		}
 	}
 
+	public async applyRemoteChangesLocally(): Promise<void> {
+		if (!this.settings.getSettings().isSyncEnabled) {
+			this.logger.debug(
+				`Syncing is disabled, not fetching remote changes`
+			);
+			return;
+		}
+
+		if (this.runningApplyRemoteChangesLocally != null) {
+			this.logger.debug(
+				"Applying remote changes locally is already in progress"
+			);
+			return this.runningApplyRemoteChangesLocally;
+		}
+
+		try {
+			this.runningApplyRemoteChangesLocally =
+				this.internalApplyRemoteChangesLocally();
+			await this.runningApplyRemoteChangesLocally;
+			this.logger.info("All remote changes have been applied locally");
+		} catch (e) {
+			this.logger.error(`Failed to apply remote changes locally: ${e}`);
+			throw e;
+		} finally {
+			this.runningApplyRemoteChangesLocally = undefined;
+		}
+	}
+
+	public async reset(): Promise<void> {
+		this.syncQueue.clear();
+		await this.syncQueue.onEmpty();
+		this.remainingOperationsListeners.forEach((listener) => {
+			listener(0);
+		});
+	}
+
+	private async syncRemotelyUpdatedFile(
+		remoteVersion: components["schemas"]["DocumentVersionWithoutContent"]
+	): Promise<void> {
+		await this.syncQueue.add(async () =>
+			this.internalSyncer.unrestrictedSyncRemotelyUpdatedFile(
+				remoteVersion
+			)
+		);
+	}
+
 	private async internalScheduleSyncForOfflineChanges(): Promise<void> {
 		const allLocalFiles = await this.operations.listAllFiles();
 
@@ -226,34 +262,6 @@ export class Syncer {
 		);
 	}
 
-	public async applyRemoteChangesLocally(): Promise<void> {
-		if (!this.settings.getSettings().isSyncEnabled) {
-			this.logger.debug(
-				`Syncing is disabled, not fetching remote changes`
-			);
-			return;
-		}
-
-		if (this.runningApplyRemoteChangesLocally != null) {
-			this.logger.debug(
-				"Applying remote changes locally is already in progress"
-			);
-			return this.runningApplyRemoteChangesLocally;
-		}
-
-		try {
-			this.runningApplyRemoteChangesLocally =
-				this.internalApplyRemoteChangesLocally();
-			await this.runningApplyRemoteChangesLocally;
-			this.logger.info("All remote changes have been applied locally");
-		} catch (e) {
-			this.logger.error(`Failed to apply remote changes locally: ${e}`);
-			throw e;
-		} finally {
-			this.runningApplyRemoteChangesLocally = undefined;
-		}
-	}
-
 	private async internalApplyRemoteChangesLocally(): Promise<void> {
 		const remote = await this.syncService.getAll(
 			this.database.getLastSeenUpdateId()
@@ -281,14 +289,6 @@ export class Syncer {
 		}
 	}
 
-	public async reset(): Promise<void> {
-		this.syncQueue.clear();
-		await this.syncQueue.onEmpty();
-		this.remainingOperationsListeners.forEach((listener) => {
-			listener(0);
-		});
-	}
-
 	private emitRemainingOperationsChange(remainingOperations: number): void {
 		this.remainingOperationsListeners.forEach((listener) => {
 			listener(remainingOperations);
diff --git a/frontend/test-client/src/agent/mock-client.ts b/frontend/test-client/src/agent/mock-client.ts
index 6fc8f15..6dc5407 100644
--- a/frontend/test-client/src/agent/mock-client.ts
+++ b/frontend/test-client/src/agent/mock-client.ts
@@ -7,9 +7,9 @@ import { SyncClient } from "sync-client";
 import { assert } from "../utils/assert";
 
 export class MockClient implements FileSystemOperations {
-	protected readonly localFiles: Record<string, Uint8Array> = {};
+	protected readonly localFiles = new Map<string, Uint8Array>();
 	protected client!: SyncClient;
-	protected data: unknown = "";
+	protected data: object | undefined = undefined;
 
 	public constructor(
 		private readonly initialSettings: Partial<SyncSettings>
@@ -18,15 +18,17 @@ export class MockClient implements FileSystemOperations {
 	public async init(): Promise<void> {
 		this.client = await SyncClient.create(this, {
 			load: async () => this.data,
-			save: async (data: unknown) => void (this.data = data)
+			save: async (data) => void (this.data = data)
 		});
 
 		await Promise.all(
 			Object.keys(this.initialSettings).map(async (key) => {
-				return this.client.settings.setSetting(
-					key as keyof SyncSettings,
-					this.initialSettings[key as keyof SyncSettings]
-				);
+				if (key in this.client.settings) {
+					return this.client.settings.setSetting(
+						key as keyof SyncSettings, // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+						this.initialSettings[key as keyof SyncSettings] // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+					);
+				}
 			})
 		);
 
@@ -37,46 +39,44 @@ export class MockClient implements FileSystemOperations {
 	}
 
 	public async listAllFiles(): Promise<RelativePath[]> {
-		return Object.keys(this.localFiles);
+		return Array.from(this.localFiles.keys());
 	}
 
 	public async read(path: RelativePath): Promise<Uint8Array> {
-		if (!(path in this.localFiles)) {
+		const file = this.localFiles.get(path);
+		if (!file) {
 			throw new Error(`File ${path} does not exist`);
 		}
-		return this.localFiles[path];
+		return file;
 	}
 
 	public async getFileSize(path: RelativePath): Promise<number> {
-		if (!(path in this.localFiles)) {
-			throw new Error(`File ${path} does not exist`);
-		}
-		return this.localFiles[path].length;
+		return (await this.read(path)).length;
 	}
 
 	public async getModificationTime(path: RelativePath): Promise<Date> {
-		if (!(path in this.localFiles)) {
+		if (!this.localFiles.has(path)) {
 			throw new Error(`File ${path} does not exist`);
 		}
 		return new Date();
 	}
 
 	public async exists(path: RelativePath): Promise<boolean> {
-		return path in this.localFiles;
+		return this.localFiles.has(path);
 	}
 
 	public async create(
 		path: RelativePath,
 		newContent: Uint8Array
 	): Promise<void> {
-		if (path in this.localFiles) {
+		if (this.localFiles.has(path)) {
 			throw new Error(`File ${path} already exists`);
 		}
-		this.localFiles[path] = newContent;
+		this.localFiles.set(path, newContent);
 		void this.client.syncer.syncLocallyCreatedFile(path, new Date());
 	}
 
-	public async createDirectory(path: RelativePath): Promise<void> {
+	public async createDirectory(_path: RelativePath): Promise<void> {
 		// This doesn't mean anything in our virtual FS representation
 	}
 
@@ -84,13 +84,14 @@ export class MockClient implements FileSystemOperations {
 		path: RelativePath,
 		updater: (currentContent: string) => string
 	): Promise<string> {
-		if (!(path in this.localFiles)) {
+		const file = this.localFiles.get(path);
+		if (!file) {
 			throw new Error(`File ${path} does not exist`);
 		}
-		const currentContent = new TextDecoder().decode(this.localFiles[path]);
+		const currentContent = new TextDecoder().decode(file);
 		const newContent = updater(currentContent);
 		const newContentUint8Array = new TextEncoder().encode(newContent);
-		this.localFiles[path] = newContentUint8Array;
+		this.localFiles.set(path, newContentUint8Array);
 
 		void this.client.syncer.syncLocallyUpdatedFile({
 			relativePath: path,
@@ -101,7 +102,7 @@ export class MockClient implements FileSystemOperations {
 	}
 
 	public async write(path: RelativePath, content: Uint8Array): Promise<void> {
-		this.localFiles[path] = content;
+		this.localFiles.set(path, content);
 
 		void this.client.syncer.syncLocallyUpdatedFile({
 			relativePath: path,
@@ -110,7 +111,7 @@ export class MockClient implements FileSystemOperations {
 	}
 
 	public async delete(path: RelativePath): Promise<void> {
-		delete this.localFiles[path];
+		this.localFiles.delete(path);
 		void this.client.syncer.syncLocallyDeletedFile(path);
 	}
 
@@ -118,13 +119,13 @@ export class MockClient implements FileSystemOperations {
 		oldPath: RelativePath,
 		newPath: RelativePath
 	): Promise<void> {
-		if (!(oldPath in this.localFiles)) {
+		const file = this.localFiles.get(oldPath);
+		if (!file) {
 			throw new Error(`File ${oldPath} does not exist`);
 		}
-
-		this.localFiles[newPath] = this.localFiles[oldPath];
+		this.localFiles.set(newPath, file);
 		if (oldPath !== newPath) {
-			delete this.localFiles[oldPath];
+			this.localFiles.delete(oldPath);
 		}
 
 		void this.client.syncer.syncLocallyUpdatedFile({