diff --git a/package.json b/package.json
index 7f06fee..e254c39 100644
--- a/package.json
+++ b/package.json
@@ -16,7 +16,7 @@
     "docs:build": "vitepress build docs",
     "docs:preview": "vitepress preview docs --host 0.0.0.0 --port 4173 --strictPort",
     "test:config": "pnpm run build && node --test dist/config/config.test.js",
-    "test:core": "pnpm run build && node --test dist/cli/args.test.js dist/cli/help.test.js dist/core/services/cli-command-service.test.js dist/core/services/numeric-shortcut-session-service.test.js dist/core/services/secondary-subtitle-service.test.js dist/core/services/mpv-render-metrics-service.test.js dist/core/services/mpv-runtime-service.test.js dist/core/services/runtime-options-runtime-service.test.js dist/core/services/overlay-modal-restore-service.test.js dist/core/services/runtime-config-service.test.js dist/core/services/overlay-bridge-runtime-service.test.js dist/core/services/overlay-visibility-facade-service.test.js dist/core/services/overlay-broadcast-runtime-service.test.js dist/core/services/app-ready-runtime-service.test.js dist/core/services/app-shutdown-runtime-service.test.js dist/core/services/mpv-client-deps-runtime-service.test.js dist/core/services/app-lifecycle-deps-runtime-service.test.js dist/core/services/runtime-options-manager-runtime-service.test.js dist/core/services/config-warning-runtime-service.test.js",
+    "test:core": "pnpm run build && node --test dist/cli/args.test.js dist/cli/help.test.js dist/core/services/cli-command-service.test.js dist/core/services/numeric-shortcut-session-service.test.js dist/core/services/secondary-subtitle-service.test.js dist/core/services/mpv-render-metrics-service.test.js dist/core/services/mpv-runtime-service.test.js dist/core/services/runtime-options-runtime-service.test.js dist/core/services/overlay-modal-restore-service.test.js dist/core/services/runtime-config-service.test.js dist/core/services/overlay-bridge-runtime-service.test.js dist/core/services/overlay-visibility-facade-service.test.js dist/core/services/overlay-broadcast-runtime-service.test.js dist/core/services/app-ready-runtime-service.test.js dist/core/services/app-shutdown-runtime-service.test.js dist/core/services/mpv-client-deps-runtime-service.test.js dist/core/services/app-lifecycle-deps-runtime-service.test.js dist/core/services/runtime-options-manager-runtime-service.test.js dist/core/services/config-warning-runtime-service.test.js dist/core/services/app-logging-runtime-service.test.js",
     "test:subtitle": "pnpm run build && node --test dist/subtitle/stages.test.js dist/subtitle/pipeline.test.js",
     "generate:config-example": "pnpm run build && node dist/generate-config-example.js",
     "start": "pnpm run build && electron . --start",
diff --git a/src/core/services/app-logging-runtime-service.test.ts b/src/core/services/app-logging-runtime-service.test.ts
new file mode 100644
index 0000000..535345d
--- /dev/null
+++ b/src/core/services/app-logging-runtime-service.test.ts
@@ -0,0 +1,28 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { createAppLoggingRuntimeService } from "./app-logging-runtime-service";
+
+test("createAppLoggingRuntimeService routes logs and formats config warnings", () => {
+  const lines: string[] = [];
+  const logger = {
+    log: (line: string) => lines.push(`log:${line}`),
+    warn: (line: string) => lines.push(`warn:${line}`),
+    error: (line: string) => lines.push(`error:${line}`),
+  };
+
+  const runtime = createAppLoggingRuntimeService(logger);
+  runtime.logInfo("hello");
+  runtime.logWarning("careful");
+  runtime.logNoRunningInstance();
+  runtime.logConfigWarning({
+    path: "x.y",
+    value: "bad",
+    fallback: "good",
+    message: "invalid",
+  });
+
+  assert.equal(lines[0], "log:hello");
+  assert.equal(lines[1], "warn:careful");
+  assert.equal(lines[2], "error:No running instance. Use --start to launch the app.");
+  assert.match(lines[3], /^warn:\[config\] x\.y: invalid /);
+});
diff --git a/src/core/services/app-logging-runtime-service.ts b/src/core/services/app-logging-runtime-service.ts
new file mode 100644
index 0000000..d9522a9
--- /dev/null
+++ b/src/core/services/app-logging-runtime-service.ts
@@ -0,0 +1,28 @@
+import { ConfigValidationWarning } from "../../types";
+import { logConfigWarningRuntimeService } from "./config-warning-runtime-service";
+
+export interface AppLoggingRuntime {
+  logInfo: (message: string) => void;
+  logWarning: (message: string) => void;
+  logNoRunningInstance: () => void;
+  logConfigWarning: (warning: ConfigValidationWarning) => void;
+}
+
+export function createAppLoggingRuntimeService(
+  logger: Pick<Console, "log" | "warn" | "error"> = console,
+): AppLoggingRuntime {
+  return {
+    logInfo: (message) => {
+      logger.log(message);
+    },
+    logWarning: (message) => {
+      logger.warn(message);
+    },
+    logNoRunningInstance: () => {
+      logger.error("No running instance. Use --start to launch the app.");
+    },
+    logConfigWarning: (warning) => {
+      logConfigWarningRuntimeService(warning, (line) => logger.warn(line));
+    },
+  };
+}
diff --git a/src/main.ts b/src/main.ts
index 7031fd7..b5f307f 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -206,7 +206,7 @@ import { runAppShutdownRuntimeService } from "./core/services/app-shutdown-runti
 import { createMpvIpcClientDepsRuntimeService } from "./core/services/mpv-client-deps-runtime-service";
 import { createAppLifecycleDepsRuntimeService } from "./core/services/app-lifecycle-deps-runtime-service";
 import { createRuntimeOptionsManagerRuntimeService } from "./core/services/runtime-options-manager-runtime-service";
-import { logConfigWarningRuntimeService } from "./core/services/config-warning-runtime-service";
+import { createAppLoggingRuntimeService } from "./core/services/app-logging-runtime-service";
 import {
   runSubsyncManualFromIpcRuntimeService,
   triggerSubsyncFromConfigRuntimeService,
@@ -236,6 +236,7 @@ const isDev =
   process.argv.includes("--dev") || process.argv.includes("--debug");
 const texthookerService = new TexthookerService();
 const subtitleWsService = new SubtitleWebSocketService();
+const appLogger = createAppLoggingRuntimeService();
 
 function getDefaultSocketPath(): string {
   if (process.platform === "win32") {
@@ -473,9 +474,7 @@ if (initialArgs.generateConfig && !shouldStartApp(initialArgs)) {
     parseArgs: (argv) => parseArgs(argv),
     handleCliCommand: (args, source) => handleCliCommand(args, source),
     printHelp: () => printHelp(DEFAULT_TEXTHOOKER_PORT),
-    logNoRunningInstance: () => {
-      console.error("No running instance. Use --start to launch the app.");
-    },
+    logNoRunningInstance: () => appLogger.logNoRunningInstance(),
     onReady: async () => {
       await runAppReadyRuntimeService({
         loadSubtitlePosition: () => loadSubtitlePosition(),
@@ -533,9 +532,7 @@ if (initialArgs.generateConfig && !shouldStartApp(initialArgs)) {
         },
         getResolvedConfig: () => getResolvedConfig(),
         getConfigWarnings: () => configService.getWarnings(),
-        logConfigWarning: (warning) => {
-          logConfigWarningRuntimeService(warning, (line) => console.warn(line));
-        },
+        logConfigWarning: (warning) => appLogger.logConfigWarning(warning),
         initRuntimeOptionsManager: () => {
           runtimeOptionsManager = createRuntimeOptionsManagerRuntimeService({
             getAnkiConfig: () => configService.getConfig().ankiConnect,
@@ -559,9 +556,7 @@ if (initialArgs.generateConfig && !shouldStartApp(initialArgs)) {
         startSubtitleWebsocket: (port) => {
           subtitleWsService.start(port, () => currentSubText);
         },
-        log: (message) => {
-          console.log(message);
-        },
+        log: (message) => appLogger.logInfo(message),
         createMecabTokenizerAndCheck: async () => {
           mecabTokenizer = new MecabTokenizer();
           await mecabTokenizer.checkAvailability();