replace file discovery by udp discovery

packages/meta-sort-core/src/api/UnifiedAPIServer.ts

@@ -11,8 +11,9 @@ import { performanceMetrics } from '../metrics/PerformanceMetrics.js';
 import { UnifiedProcessingStateManager } from '../logic/UnifiedProcessingStateManager.js';
 import type { IKVClient } from '../kv/IKVClient.js';
 import type { KVManager } from '../kv/KVManager.js';
-import type { ExtendedProcessingSnapshot, IKVClientWithPubSub } from '../types/ExtendedInterfaces.js';
+import type { ExtendedProcessingSnapshot } from '../types/ExtendedInterfaces.js';
-import { getErrorMessage } from '../types/ExtendedInterfaces.js';
+import { getErrorMessage, hasFileTuples } from '../types/ExtendedInterfaces.js';
+import type { IKVClientWithFileTuples } from '../types/ExtendedInterfaces.js';
 import { config } from '../config/EnvConfig.js';
 import * as webdav from '../webdav/WebdavClient.js';
 import type { PluginManager } from '../plugin-engine/PluginManager.js';
@@ -29,6 +30,45 @@ export interface UnifiedAPIServerConfig {
   enableCors?: boolean;
 }
 
+/** File totals served by /api/stats. Null when meta-core cannot supply them. */
+interface FileStats {
+  fileCount: number | null;
+  totalSize: number | null;
+  source: 'meta-core' | 'unavailable';
+}
+
+/** Metadata reads in flight at once while a recompute builds its task list. */
+const RECOMPUTE_READ_CONCURRENCY = 8;
+
+/** Run `worker` over `items` with at most `limit` calls in flight. */
+async function forEachWithConcurrency<T>(
+  items: readonly T[],
+  limit: number,
+  worker: (item: T) => Promise<void>
+): Promise<void> {
+  let next = 0;
+  const runners = Array.from({ length: Math.min(limit, items.length) }, async () => {
+    while (next < items.length) {
+      const item = items[next++];
+      await worker(item);
+    }
+  });
+  await Promise.all(runners);
+}
+
+/** Flatten nested metadata into the `a/b/c` keys the task scheduler expects. */
+function flattenMetadata(obj: Record<string, unknown>, out: Record<string, string> = {}, prefix = ''): Record<string, string> {
+  for (const [key, value] of Object.entries(obj)) {
+    const fullKey = prefix ? `${prefix}/${key}` : key;
+    if (value !== null && typeof value === 'object' && !Array.isArray(value)) {
+      flattenMetadata(value as Record<string, unknown>, out, fullKey);
+    } else if (value !== undefined && value !== null) {
+      out[fullKey] = String(value);
+    }
+  }
+  return out;
+}
+
 export class UnifiedAPIServer {
   private app: FastifyInstance;
   private unifiedStateManager: UnifiedProcessingStateManager | null = null;
@@ -44,9 +84,15 @@ export class UnifiedAPIServer {
   private containerPluginScheduler: ContainerPluginScheduler | null = null;
   private streamingPipeline: StreamingPipeline | null = null;
 
-  // Cache for total file size (avoid running du on every request)
+  // /api/stats file totals: stale-while-revalidate, one refresh at a time.
-  private totalSizeCache: { value: number; timestamp: number } | null = null;
+  // Never walk hashIds for these — on a shared meta-core that is every gateway
-  private static TOTAL_SIZE_CACHE_TTL_MS = 30000; // 30 seconds
+  // record too (82k on watch.nsl.sh), and a sweep per poll stacked unbounded.
+  private fileStats: { value: FileStats; fetchedAt: number } | null = null;
+  private fileStatsInFlight: Promise<FileStats> | null = null;
+  private static FILE_STATS_TTL_MS = 30000; // 30 seconds
+
+  // Plugins whose recompute is currently being queued (single-flight per plugin)
+  private recomputeInFlight = new Set<string>();
 
   constructor(
     config: UnifiedAPIServerConfig = {},
@@ -97,48 +143,46 @@ export class UnifiedAPIServer {
   }
 
   /**
-   * Get total size of processed files from Redis sizeByte field (cached)
+   * File count + total size of the files meta-core holds on disk, for the
-   * This is "eventually correct" - accumulates as files are processed by the file-info plugin
+   * monitor's "Total Size" card: one summary call to meta-core's
+   * GET /api/files/tuples (batched server-side), cached for FILE_STATS_TTL_MS.
+   *
+   * Stale-while-revalidate with a single in-flight refresh — a poll never waits
+   * on meta-core once a value exists, and concurrent polls share one request.
    */
-  private async getTotalFileSizeFromRedis(): Promise<number> {
+  private async getFileStats(): Promise<FileStats> {
-    // Check cache
+    const cached = this.fileStats;
-    const now = Date.now();
+    if (cached && Date.now() - cached.fetchedAt < UnifiedAPIServer.FILE_STATS_TTL_MS) {
-    if (this.totalSizeCache && (now - this.totalSizeCache.timestamp) < UnifiedAPIServer.TOTAL_SIZE_CACHE_TTL_MS) {
+      return cached.value;
-      return this.totalSizeCache.value;
     }
 
-    // Sum sizeByte from all file entries in Redis
+    if (!this.fileStatsInFlight) {
-    let totalSize = 0;
+      this.fileStatsInFlight = this.fetchFileStats()
-
+        .catch((error: unknown): FileStats => {
-    if (!this.kvClient) {
+          console.warn('[API] /api/stats: meta-core file totals unavailable:', getErrorMessage(error));
-      return 0;
+          return cached?.value ?? { fileCount: null, totalSize: null, source: 'unavailable' };
+        })
+        .then((value) => {
+          this.fileStats = { value, fetchedAt: Date.now() };
+          return value;
+        })
+        .finally(() => {
+          this.fileStatsInFlight = null;
+        });
     }
 
-    try {
+    return cached ? cached.value : this.fileStatsInFlight;
-      // Get all file hash IDs
-      const hashIds = await this.kvClient.getAllHashIds();
-
-      // Sum up sizeByte values (batch process for efficiency)
-      for (const hashId of hashIds) {
-        try {
-          const sizeByte = await this.kvClient.getMetadata(hashId, 'sizeByte');
-          if (sizeByte !== null && sizeByte !== undefined) {
-            const size = typeof sizeByte === 'number' ? sizeByte : parseInt(String(sizeByte), 10);
-            if (!isNaN(size) && size > 0) {
-              totalSize += size;
-            }
-          }
-        } catch {
-          // Skip entries without sizeByte
-        }
-      }
-    } catch (error) {
-      console.warn('[API] Failed to calculate total size from Redis:', error);
   }
 
-    // Update cache
+  private async fetchFileStats(): Promise<FileStats> {
-    this.totalSizeCache = { value: totalSize, timestamp: now };
+    if (!this.kvClient || !hasFileTuples(this.kvClient)) {
-    return totalSize;
+      return { fileCount: null, totalSize: null, source: 'unavailable' };
+    }
+    const summary = await this.kvClient.getFileTuples({ summary: true });
+    if (!summary) {
+      return { fileCount: null, totalSize: null, source: 'unavailable' };
+    }
+    return { fileCount: summary.count, totalSize: summary.totalSize, source: 'meta-core' };
   }
 
   /**
@@ -193,7 +237,7 @@ export class UnifiedAPIServer {
       this.setupStatsRoutes();
     }
 
-    // Service discovery — proxies to meta-core's /api/services using the
+    // Service discovery — meta-discovery v1 neighbour list, served from the
     // LeaderClient to resolve meta-core's current URL dynamically.
     this.setupServiceDiscoveryRoutes();
 
@@ -524,53 +568,17 @@ export class UnifiedAPIServer {
 
 
   /**
-   * Setup Stats API routes (Redis stats for monitor UI)
+   * Setup Stats API routes (file totals for the monitor UI)
    */
   private setupStatsRoutes(): void {
     if (!this.kvClient) {
       return;
     }
 
-    // Get Redis/KV stats (for monitor UI)
+    // At most one meta-core call per FILE_STATS_TTL_MS however often the
-    this.app.get('/api/stats', async (request, reply) => {
+    // monitor polls — see getFileStats.
-      try {
+    this.app.get('/api/stats', async () => {
-        const hashIds = await this.kvClient!.getAllHashIds();
+      return this.getFileStats();
-        const redis = (this.kvClient as IKVClientWithPubSub).getRedisClient?.() as { info: (section: string) => Promise<string> } | undefined;
-
-        let memoryUsage = 'N/A';
-        let memoryUsageBytes = 0;
-        if (redis) {
-          try {
-            const info = await redis.info('memory');
-            const match = info.match(/used_memory_human:(\S+)/);
-            const bytesMatch = info.match(/used_memory:(\d+)/);
-            if (match) {
-              memoryUsage = match[1];
-            }
-            if (bytesMatch) {
-              memoryUsageBytes = parseInt(bytesMatch[1], 10);
-            }
-          } catch {
-            // Ignore memory info errors
-          }
-        }
-
-        // Get total size from Redis sizeByte (eventually correct as files are processed)
-        const totalSize = await this.getTotalFileSizeFromRedis();
-
-        return {
-          fileCount: hashIds.length,
-          keyCount: hashIds.length,
-          totalSize,
-          memoryUsage,
-          memoryUsageBytes
-        };
-      } catch (error: any) {
-        return reply.status(500).send({
-          error: 'Failed to get stats',
-          details: error.message
-        });
-      }
     });
   }
 
@@ -584,33 +592,28 @@ export class UnifiedAPIServer {
   }
 
   /**
-   * Service discovery — proxies to meta-core's /api/services, resolving the
+   * Service discovery — meta-discovery v1. Served from this service's own UDP
-   * current leader's URL via LeaderClient (no hardcoded hostname).
+   * neighbour map; no meta-core round trip, so the nav survives a core outage.
    */
   private setupServiceDiscoveryRoutes(): void {
-    this.app.get('/api/services', async (_request, reply) => {
+    // meta-discovery v1: neighbours heard over UDP, served from this service's
-      try {
+    // own map. Unlike /api/services below it needs no meta-core, so the nav
+    // still renders when the core is down. `services` is kept as an alias
+    // while any older dashboard build is still in circulation.
+    this.app.get('/api/neighbors', async (_request, reply) => {
       const leaderClient = this.kvManager?.getLeaderClient();
       if (!leaderClient) {
-          return reply.status(503).send({ error: 'KVManager not initialized' });
+        return reply.send({ current: 'meta-sort', enabled: false, count: 0, neighbors: [] });
       }
-        const apiUrl = await leaderClient.getApiUrl();
+      const neighbors = leaderClient.getNeighbors();
-        if (!apiUrl) {
+      return reply.send({
-          return reply.status(503).send({ error: 'Leader not available yet' });
+        current: 'meta-sort',
-        }
+        enabled: true,
-        const response = await fetch(`${apiUrl}/api/services`, {
+        count: neighbors.length,
-          signal: AbortSignal.timeout(5000),
+        neighbors,
+        services: neighbors,
+        self: leaderClient.self(),
       });
-        if (!response.ok) {
-          return reply.status(response.status).send({
-            error: `Upstream ${apiUrl} returned ${response.status}`,
-          });
-        }
-        const body = await response.json();
-        return reply.send(body);
-      } catch (err) {
-        return reply.status(502).send({ error: getErrorMessage(err) });
-      }
     });
   }
 
@@ -886,38 +889,43 @@ export class UnifiedAPIServer {
         return reply.status(400).send({ error: `Plugin '${pluginId}' is not active` });
       }
 
+      if (!hasFileTuples(this.kvClient)) {
+        return reply.status(501).send({ error: 'Recompute needs meta-core GET /api/files/tuples' });
+      }
+      const kvClient = this.kvClient as IKVClientWithFileTuples;
+
+      if (this.recomputeInFlight.has(pluginId)) {
+        return reply.status(409).send({ error: `Recompute for plugin '${pluginId}' is already being queued` });
+      }
+
+      this.recomputeInFlight.add(pluginId);
       try {
-        // Get all files from KV
+        // Only file-backed records can be recomputed, and meta-core lists exactly
-        const hashIds = await this.kvClient.getAllHashIds();
+        // those in one batched call. Walking getAllHashIds() instead reads every
-        console.log(`[Recompute] Starting recompute for plugin '${pluginId}' on ${hashIds.length} files`);
+        // gateway record too (82k on watch.nsl.sh) to keep a few thousand.
+        const tuples = await kvClient.getFileTuples();
+        if (!tuples || !tuples.files) {
+          return reply.status(501).send({
+            error: 'Recompute needs meta-core GET /api/files/tuples',
+            details: 'meta-core did not return a file list'
+          });
+        }
+        const candidates = tuples.files;
+        console.log(`[Recompute] Starting recompute for plugin '${pluginId}' on ${candidates.length} files`);
 
         // Prepare file data with metadata for TaskScheduler
         const files: Array<{ filePath: string; fileHash: string; kvData?: Record<string, string> }> = [];
-
+        await forEachWithConcurrency(candidates, RECOMPUTE_READ_CONCURRENCY, async (tuple) => {
-        for (const hashId of hashIds) {
+          const metadata = await kvClient.getMetadataFlat(tuple.hashId);
-          const metadata = await this.kvClient.getMetadataFlat(hashId);
+          if (!metadata) {
-          if (metadata && metadata.filePath) {
+            return;
-            // Convert nested metadata to flat key-value pairs for KVStore
-            const kvData: Record<string, string> = {};
-            const flattenObj = (obj: any, prefix = '') => {
-              for (const [key, value] of Object.entries(obj)) {
-                const fullKey = prefix ? `${prefix}/${key}` : key;
-                if (value !== null && typeof value === 'object' && !Array.isArray(value)) {
-                  flattenObj(value, fullKey);
-                } else if (value !== undefined && value !== null) {
-                  kvData[fullKey] = String(value);
           }
-              }
-            };
-            flattenObj(metadata);
-
           files.push({
-              fileHash: hashId,
+            fileHash: tuple.hashId,
-              filePath: metadata.filePath,
+            filePath: metadata.filePath || tuple.filePath,
-              kvData
+            kvData: flattenMetadata(metadata)
+          });
         });
-          }
-        }
 
         // Create and enqueue tasks with forceRecompute option
         const tasks = taskScheduler.createTasksForPluginOnFiles(
@@ -935,7 +943,7 @@ export class UnifiedAPIServer {
           status: 'ok',
           message: `Recompute triggered for plugin '${pluginId}'`,
           filesQueued: tasks.length,
-          totalFiles: hashIds.length
+          totalFiles: candidates.length
         };
       } catch (error: any) {
         console.error(`[Recompute] Error triggering recompute for plugin '${pluginId}':`, error);
@@ -943,6 +951,8 @@ export class UnifiedAPIServer {
           error: 'Failed to trigger recompute',
           details: error.message
         });
+      } finally {
+        this.recomputeInFlight.delete(pluginId);
       }
     });
   }

packages/meta-sort-core/src/api/api.test.ts

@@ -8,6 +8,7 @@
 import { expect } from 'chai';
 import { UnifiedAPIServer } from './UnifiedAPIServer.js';
 import { UnifiedProcessingStateManager } from '../logic/UnifiedProcessingStateManager.js';
+import { performanceMetrics } from '../metrics/PerformanceMetrics.js';
 import type { IKVClient } from '../kv/IKVClient.js';
 import type { FastifyInstance } from 'fastify';
 
@@ -23,6 +24,25 @@ class MockKVClient implements IKVClient {
     private data: Map<string, Map<string, any>> = new Map();
     private rawStore: Map<string, string> = new Map();
 
+    // Stand-in for meta-core's GET /api/files/tuples. null = a meta-core that
+    // predates the endpoint.
+    fileTuples: Array<{ hashId: string; filePath: string; sizeByte: number; mtimeNano: number }> | null = null;
+    fileTuplesDelayMs = 0;
+    calls = { getFileTuples: 0, getAllHashIds: 0, getMetadataFlat: 0 };
+
+    async getFileTuples(opts: { summary?: boolean } = {}) {
+        this.calls.getFileTuples++;
+        if (this.fileTuplesDelayMs) {
+            await new Promise(resolve => setTimeout(resolve, this.fileTuplesDelayMs));
+        }
+        if (!this.fileTuples) return null;
+        const files = this.fileTuples;
+        const totalSize = files.reduce((sum, f) => sum + f.sizeByte, 0);
+        return opts.summary
+            ? { count: files.length, totalSize }
+            : { count: files.length, totalSize, files };
+    }
+
     // Basic operations
     async set(key: string, value: any): Promise<void> {
         this.rawStore.set(key, JSON.stringify(value));
@@ -99,6 +119,7 @@ class MockKVClient implements IKVClient {
     }
 
     async getMetadataFlat(hashId: string): Promise<any | null> {
+        this.calls.getMetadataFlat++;
         const entry = this.data.get(hashId);
         if (!entry) return null;
         return Object.fromEntries(entry);
@@ -125,6 +146,7 @@ class MockKVClient implements IKVClient {
     }
 
     async getAllHashIds(): Promise<string[]> {
+        this.calls.getAllHashIds++;
         return Array.from(this.data.keys());
     }
 
@@ -736,3 +758,157 @@ describe('UnifiedAPIServer', function() {
         });
     });
 });
+
+// =============================================================================
+// File totals + recompute against meta-core's GET /api/files/tuples
+// =============================================================================
+//
+// Each test builds its own server: /api/stats caches for 30 s and recompute is
+// single-flight, so shared state between tests would hide both behaviours.
+
+describe('UnifiedAPIServer file totals and recompute', function() {
+    const tuple = (hashId: string, sizeByte: number) =>
+        ({ hashId, filePath: `/files/watch/${hashId}.mkv`, sizeByte, mtimeNano: 1 });
+
+    let app: FastifyInstance;
+    let kv: MockKVClient;
+    let queued: Array<{ pluginId: string; fileHash: string }>;
+
+    beforeEach(async function() {
+        kv = new MockKVClient();
+        queued = [];
+        const pluginManager = { getPlugins: () => [{ id: 'ffmpeg', active: true }] };
+        const taskScheduler = {
+            createTasksForPluginOnFiles: (pluginId: string, files: Array<{ fileHash: string }>) =>
+                files.map(f => ({ pluginId, fileHash: f.fileHash })),
+            enqueueTasks: (tasks: Array<{ pluginId: string; fileHash: string }>) => { queued.push(...tasks); },
+        };
+        const server = new UnifiedAPIServer(
+            { port: 0, host: 'localhost', enableCors: false },
+            new MockProcessingStateManager() as any,
+            kv as any,
+            4,
+            16,
+            () => ({ fast: { pending: 0, running: 0 }, background: { pending: 0, running: 0 } }),
+            undefined,
+            () => pluginManager as any,
+            () => taskScheduler as any
+        );
+        app = server.getApp();
+        await app.ready();
+    });
+
+    afterEach(async function() {
+        await app.close();
+    });
+
+    it('GET /api/stats sums meta-core file tuples without walking hash ids', async function() {
+        kv.fileTuples = [tuple('a', 100), tuple('b', 250)];
+
+        const response = await app.inject({ method: 'GET', url: '/api/stats' });
+
+        expect(response.statusCode).to.equal(200);
+        expect(JSON.parse(response.payload)).to.deep.equal({ fileCount: 2, totalSize: 350, source: 'meta-core' });
+        expect(kv.calls.getAllHashIds).to.equal(0);
+        expect(kv.calls.getMetadataFlat).to.equal(0);
+    });
+
+    it('GET /api/stats degrades to nulls on a meta-core without the endpoint', async function() {
+        kv.fileTuples = null;
+
+        const response = await app.inject({ method: 'GET', url: '/api/stats' });
+
+        expect(response.statusCode).to.equal(200);
+        expect(JSON.parse(response.payload)).to.deep.equal({ fileCount: null, totalSize: null, source: 'unavailable' });
+        expect(kv.calls.getAllHashIds).to.equal(0);
+    });
+
+    it('GET /api/stats shares one meta-core call between concurrent polls', async function() {
+        kv.fileTuples = [tuple('a', 100)];
+        kv.fileTuplesDelayMs = 50;
+
+        const responses = await Promise.all(
+            Array.from({ length: 10 }, () => app.inject({ method: 'GET', url: '/api/stats' }))
+        );
+
+        for (const response of responses) {
+            expect(response.statusCode).to.equal(200);
+            expect(JSON.parse(response.payload).totalSize).to.equal(100);
+        }
+        expect(kv.calls.getFileTuples).to.equal(1);
+    });
+
+    it('POST recompute returns 501 on a meta-core without the endpoint', async function() {
+        kv.fileTuples = null;
+
+        const response = await app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' });
+
+        expect(response.statusCode).to.equal(501);
+        expect(kv.calls.getAllHashIds).to.equal(0);
+        expect(queued).to.have.length(0);
+    });
+
+    it('POST recompute queues only file-backed records', async function() {
+        kv.seedData('a', { filePath: '/files/watch/a.mkv', fileType: 'video' });
+        kv.seedData('b', { filePath: '/files/watch/b.mkv', fileType: 'video' });
+        kv.seedData('gateway-record', { title: 'Not a file' });
+        kv.fileTuples = [tuple('a', 100), tuple('b', 250)];
+
+        const response = await app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' });
+
+        expect(response.statusCode).to.equal(200);
+        const body = JSON.parse(response.payload);
+        expect(body.filesQueued).to.equal(2);
+        expect(body.totalFiles).to.equal(2);
+        expect(queued.map(q => q.fileHash).sort()).to.deep.equal(['a', 'b']);
+        expect(kv.calls.getMetadataFlat).to.equal(2);
+        expect(kv.calls.getAllHashIds).to.equal(0);
+    });
+
+    it('POST recompute refuses a second run for the same plugin while one is queuing', async function() {
+        kv.seedData('a', { filePath: '/files/watch/a.mkv' });
+        kv.fileTuples = [tuple('a', 100)];
+        kv.fileTuplesDelayMs = 50;
+
+        const [first, second] = await Promise.all([
+            app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' }),
+            app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' }),
+        ]);
+
+        expect([first.statusCode, second.statusCode].sort()).to.deep.equal([200, 409]);
+        expect(queued).to.have.length(1);
+    });
+});
+
+// =============================================================================
+// File-level processing metric
+// =============================================================================
+
+describe('UnifiedProcessingStateManager file metric', function() {
+    // Files announced over SSE go straight to light processing; they are never
+    // marked discovered, which is the path that used to leave "Processed" at 0.
+    const runFile = (manager: UnifiedProcessingStateManager, filePath: string, error?: string) => {
+        manager.startLightProcessing(filePath);
+        manager.completeLightProcessing(filePath, 'bagacbabaeexamplehash');
+        manager.startHashProcessing(filePath);
+        manager.completeHashProcessing(filePath, 'bagacbabaeexamplehash', undefined, error);
+    };
+
+    it('counts a file as processed when its hash phase completes cleanly', function() {
+        const manager = new UnifiedProcessingStateManager();
+        const before = performanceMetrics.getMetrics().totalFilesProcessed;
+
+        runFile(manager, '/files/watch/metric-ok.mkv');
+
+        expect(performanceMetrics.getMetrics().totalFilesProcessed).to.equal(before + 1);
+    });
+
+    it('does not count a file whose hash phase failed', function() {
+        const manager = new UnifiedProcessingStateManager();
+        const before = performanceMetrics.getMetrics().totalFilesProcessed;
+
+        runFile(manager, '/files/watch/metric-failed.mkv', 'plugin failed');
+
+        expect(performanceMetrics.getMetrics().totalFilesProcessed).to.equal(before);
+    });
+});

packages/meta-sort-core/src/config/RenamingRule.ts

@@ -26,7 +26,8 @@ export function renamingRule(metamesh: Local, filepath?: string): string | null
         throw new Error(`No extension found for file: ${filepath}`);
     }
 
-    const title = metamesh?.titles?.eng || metamesh.originalTitle;
+    // The display name — never the `titles/*` name set, which has no preferred member (METADATA_KEYS.md §3).
+    const title = metamesh.title || metamesh.originalTitle;
     if (!title) {
         if (metamesh.fileType !== "torrent") {
             //don't warn for torrent files because they don't always have a title (eg representing a folder of files)

packages/meta-sort-core/src/container-plugins/ContainerManager.ts

@@ -142,53 +142,18 @@ export class ContainerManager extends EventEmitter {
             return;
         }
 
-        // Fall back to service discovery for any missing URLs
+        // Anything still missing is a configuration problem, not something to
-        const serviceFile = join(config.META_CORE_PATH, 'services', 'meta-sort.json');
+        // guess at. The old fallback here read
-
+        // `${META_CORE_PATH}/services/meta-sort.json` — a filename that stopped
-        try {
+        // existing when registration files became hostname-suffixed, using a
-            const content = await fs.readFile(serviceFile, 'utf-8');
+        // schema (`.api` / `.endpoints`) that no longer matched either. It had
-            const serviceInfo: ServiceInfo = JSON.parse(content);
+        // been falling into its own catch block for a long time, and the
-
+        // volume it read is gone since meta-discovery v1.
-            // Extract URLs from service info
-            const api = serviceInfo.api;
-            const endpoints = serviceInfo.endpoints || {};
-
-            // Use service discovery for callback URL if not set
         if (!this.callbackUrl) {
-                if (endpoints.callback) {
+            console.warn('[ContainerManager] No callback URL — set CONTAINER_CALLBACK_URL');
-                    this.callbackUrl = endpoints.callback;
-                    console.log(`[ContainerManager] Discovered callback URL: ${this.callbackUrl}`);
-                } else if (api) {
-                    // Fallback: construct from api base
-                    this.callbackUrl = `${api}/api/plugins/callback`;
-                    console.log(`[ContainerManager] Constructed callback URL: ${this.callbackUrl}`);
         }
-            }
-
-            // Use service discovery for WebDAV URL if not set (fallback)
         if (!this.webdavUrl) {
-                if (endpoints.webdav) {
+            console.warn('[ContainerManager] No WebDAV URL — meta-core did not supply one');
-                    this.webdavUrl = endpoints.webdav;
-                    console.log(`[ContainerManager] Discovered WebDAV URL: ${this.webdavUrl}`);
-                } else if (api) {
-                    // Fallback: construct from api base
-                    this.webdavUrl = `${api}/webdav`;
-                    console.log(`[ContainerManager] Constructed WebDAV URL: ${this.webdavUrl}`);
-                }
-            }
-
-            if (endpoints.health) {
-                // Extract meta-core URL from health endpoint
-                const healthUrl = new URL(endpoints.health);
-                this.metaCoreUrl = `${healthUrl.protocol}//${healthUrl.host}`;
-                console.log(`[ContainerManager] Discovered meta-core URL: ${this.metaCoreUrl}`);
-            }
-
-            console.log('[ContainerManager] Service discovery successful');
-        } catch (error) {
-            console.warn(`[ContainerManager] Service discovery failed: ${error}`);
-            console.log(`[ContainerManager] Using callback URL: ${this.callbackUrl}`);
-            console.log(`[ContainerManager] Using WebDAV URL: ${this.webdavUrl || 'not set'}`);
         }
     }
 

packages/meta-sort-core/src/discovery/meshdisco.ts

@@ -0,0 +1,441 @@
+/**
+ * meta-discovery v1 — UDP multicast service discovery.
+ *
+ * Replaces the two file-based mechanisms that required a shared /meta-core
+ * volume: `locks/kv-leader.info` (locating meta-core at boot) and
+ * `services/<name>-<host>.json` (the dashboard nav registry). Both answered the
+ * same question — where is meta-core, and who else is on this network — so one
+ * announce packet answers both, and discovery scope becomes the docker network
+ * rather than the mounted volume.
+ *
+ * The normative spec is docs/project-architecture/service-discovery.md.
+ *
+ * ⚠ MIRRORED FILE. Byte-identical copies live in meta-sort-core, meta-fuse-core
+ * and meta-dup-core. They cannot share a package: meta-fuse-core and
+ * meta-dup-core do not depend on @metazla/meta-interface at all, and each
+ * submodule is its own Docker build context, so a workspace dep resolves
+ * outside the build. Edit one copy → edit all three, and
+ * `scripts/check-mirrors.sh` will tell you if you forgot.
+ */
+
+import dgram from 'dgram';
+import { hostname, networkInterfaces } from 'os';
+
+export const PROTOCOL_VERSION = 1;
+export const DEFAULT_GROUP = '239.255.77.1';
+export const DEFAULT_PORT = 9399;
+export const DEFAULT_INTERVAL_MS = 10_000;
+/** A neighbour unseen for interval × this is dropped. Replaces the reaper. */
+export const LIVENESS_FACTOR = 3;
+
+export const TYPE_DISCOVERY = 'discovery';
+export const TYPE_ANNOUNCE = 'announce';
+export const ROLE_CORE = 'core';
+export const ROLE_SERVICE = 'service';
+
+/** Mirrors meta-core's GET /urls response minus redisUrl (retired). */
+export interface MeshUrls {
+    hostname: string;
+    baseUrl: string;
+    apiUrl: string;
+    webdavUrl: string;
+    webdavUrlInternal: string;
+}
+
+export interface MeshMessage {
+    v: number;
+    type: string;
+    name?: string;
+    instance?: string;
+    role?: string;
+    version?: string;
+    status?: string;
+    baseUrl?: string;
+    /** Present only when role === 'core'. */
+    urls?: MeshUrls;
+    /** Reserved for a future HMAC; v1 ignores it. */
+    token?: string;
+}
+
+export interface MeshNeighbor extends MeshMessage {
+    /** Source address taken from the packet, never from the payload. */
+    addr: string;
+    lastSeen: number;
+}
+
+export interface MeshNodeConfig {
+    name: string;
+    instance?: string;
+    role?: string;
+    version?: string;
+    group?: string;
+    port?: number;
+    intervalMs?: number;
+    enabled?: boolean;
+    /** Rebuilt on every announce so the payload never goes stale. */
+    payload?: () => { baseUrl?: string; status?: string; urls?: MeshUrls };
+}
+
+/** IPv4 addresses of every up, non-internal interface. */
+function localInterfaceAddresses(): string[] {
+    const out: string[] = [];
+    const nets = networkInterfaces();
+    for (const name of Object.keys(nets)) {
+        for (const ni of nets[name] ?? []) {
+            // Node has flip-flopped between 'IPv4' and 4 for `family`.
+            const isV4 = (ni as { family: string | number }).family === 'IPv4' ||
+                (ni as { family: string | number }).family === 4;
+            if (isV4 && !ni.internal && ni.address) out.push(ni.address);
+        }
+    }
+    return out;
+}
+
+/** First non-internal IPv4 address, or the hostname. Matches the Go helper. */
+export function localIPv4(): string {
+    return localInterfaceAddresses()[0] ?? hostname();
+}
+
+/**
+ * One participant in the mesh: announces itself, answers probes, and keeps a
+ * TTL map of everyone else.
+ */
+export class MeshNode {
+    private cfg: Required<Omit<MeshNodeConfig, 'payload'>> & Pick<MeshNodeConfig, 'payload'>;
+    private socket: dgram.Socket | null = null;
+    private timer: NodeJS.Timeout | null = null;
+    private neighbors = new Map<string, MeshNeighbor>();
+    private ifaceAddrs: string[] = [];
+    private listeners: ((n: MeshNeighbor) => void)[] = [];
+    private started = false;
+
+    constructor(config: MeshNodeConfig) {
+        this.cfg = {
+            name: config.name,
+            instance: config.instance ?? hostname(),
+            role: config.role ?? ROLE_SERVICE,
+            version: config.version ?? '',
+            group: config.group ?? DEFAULT_GROUP,
+            port: config.port ?? DEFAULT_PORT,
+            intervalMs: config.intervalMs ?? DEFAULT_INTERVAL_MS,
+            enabled: config.enabled ?? true,
+            payload: config.payload,
+        };
+    }
+
+    async start(): Promise<void> {
+        if (this.started || !this.cfg.enabled) {
+            if (!this.cfg.enabled) console.log('[meshdisco] Disabled by configuration');
+            return;
+        }
+        this.started = true;
+
+        await new Promise<void>((resolve) => {
+            const socket = dgram.createSocket({ type: 'udp4', reuseAddr: true });
+            this.socket = socket;
+
+            socket.on('message', (buf, rinfo) => this.onMessage(buf, rinfo));
+            socket.on('error', (err) => {
+                // Never fatal: a host that blocks multicast must degrade, not
+                // take the service down.
+                console.error('[meshdisco] Socket error:', err.message);
+            });
+
+            socket.bind(this.cfg.port, '0.0.0.0', () => {
+                try {
+                    socket.setMulticastTTL(1); // link-local only
+                } catch (e) {
+                    console.warn('[meshdisco] Could not set multicast TTL:', e);
+                }
+
+                // Join on EVERY interface. A container on two docker networks
+                // that joins only the default route silently sees one network.
+                this.ifaceAddrs = localInterfaceAddresses();
+                let joined = 0;
+                for (const addr of this.ifaceAddrs) {
+                    try {
+                        socket.addMembership(this.cfg.group, addr);
+                        joined++;
+                    } catch (e) {
+                        console.warn(`[meshdisco] Join ${this.cfg.group} on ${addr} failed:`, e);
+                    }
+                }
+                console.log(
+                    `[meshdisco] Listening on ${this.cfg.group}:${this.cfg.port} as ` +
+                    `${this.cfg.name}/${this.cfg.instance} (joined ${joined} of ${this.ifaceAddrs.length} interfaces)`
+                );
+                resolve();
+            });
+        });
+
+        this.announce();
+        this.probe();
+        this.timer = setInterval(() => this.announce(), this.cfg.intervalMs);
+        // Don't hold the event loop open on shutdown.
+        this.timer.unref?.();
+    }
+
+    async stop(): Promise<void> {
+        if (!this.started) return;
+        this.started = false;
+        if (this.timer) { clearInterval(this.timer); this.timer = null; }
+        // Final "stopping" announce so neighbours drop us immediately rather
+        // than waiting out the staleness window.
+        this.announce('stopping');
+        await new Promise<void>((resolve) => {
+            if (!this.socket) return resolve();
+            try { this.socket.close(() => resolve()); } catch { resolve(); }
+        });
+        this.socket = null;
+        this.listeners = [];
+    }
+
+    /** Multicast a probe; every listener replies immediately. */
+    probe(): void {
+        this.send({ v: PROTOCOL_VERSION, type: TYPE_DISCOVERY });
+    }
+
+    /** Everyone heard from inside the staleness window, sorted by name. */
+    getNeighbors(): MeshNeighbor[] {
+        const cutoff = Date.now() - this.cfg.intervalMs * LIVENESS_FACTOR;
+        const out: MeshNeighbor[] = [];
+        for (const [key, nb] of this.neighbors) {
+            if (nb.lastSeen < cutoff) { this.neighbors.delete(key); continue; }
+            out.push(nb);
+        }
+        return out.sort((a, b) => (a.name ?? '').localeCompare(b.name ?? ''));
+    }
+
+    /** One row per service name, most recently seen instance wins. */
+    getNeighborsByName(): MeshNeighbor[] {
+        const best = new Map<string, MeshNeighbor>();
+        for (const nb of this.getNeighbors()) {
+            const cur = best.get(nb.name ?? '');
+            if (!cur || nb.lastSeen > cur.lastSeen) best.set(nb.name ?? '', nb);
+        }
+        return [...best.values()].sort((a, b) => (a.name ?? '').localeCompare(b.name ?? ''));
+    }
+
+    /** Cores only — what a locator filters on. */
+    getCores(): MeshNeighbor[] {
+        return this.getNeighbors().filter((n) => n.role === ROLE_CORE && n.urls);
+    }
+
+    /** This node's own announce, so a UI can render itself without waiting. */
+    self(): MeshNeighbor {
+        return { ...this.buildAnnounce('running'), addr: '', lastSeen: Date.now() };
+    }
+
+    /** Fires for every announce received (after the self-echo filter). */
+    onAnnounce(cb: (n: MeshNeighbor) => void): void {
+        this.listeners.push(cb);
+    }
+
+    private onMessage(buf: Buffer, rinfo: dgram.RemoteInfo): void {
+        let msg: MeshMessage;
+        try {
+            msg = JSON.parse(buf.toString('utf8')) as MeshMessage;
+        } catch {
+            return; // foreign traffic on the group
+        }
+        if (msg.v !== PROTOCOL_VERSION) return;
+        // Drop our own multicast echo.
+        if (msg.instance && msg.instance === this.cfg.instance && msg.name === this.cfg.name) return;
+
+        if (msg.type === TYPE_DISCOVERY) {
+            this.replyTo(rinfo);
+            return;
+        }
+        if (msg.type !== TYPE_ANNOUNCE || !msg.name) return;
+
+        const key = msg.instance ? `${msg.name}|${msg.instance}` : msg.name;
+        if (msg.status === 'stopping') { this.neighbors.delete(key); return; }
+
+        const nb: MeshNeighbor = { ...msg, addr: rinfo.address, lastSeen: Date.now() };
+        this.neighbors.set(key, nb);
+        for (const cb of this.listeners) {
+            try { cb(nb); } catch (e) { console.error('[meshdisco] Listener threw:', e); }
+        }
+    }
+
+    private buildAnnounce(status: string): MeshMessage {
+        const msg: MeshMessage = {
+            v: PROTOCOL_VERSION,
+            type: TYPE_ANNOUNCE,
+            name: this.cfg.name,
+            instance: this.cfg.instance,
+            role: this.cfg.role,
+            version: this.cfg.version,
+            status,
+        };
+        if (this.cfg.payload) {
+            const p = this.cfg.payload();
+            if (p.baseUrl) msg.baseUrl = p.baseUrl;
+            if (p.status && status === 'running') msg.status = p.status;
+            // Only a core may carry a URLs block — a service announcing one
+            // would let any container impersonate meta-core.
+            if (this.cfg.role === ROLE_CORE && p.urls) msg.urls = p.urls;
+        }
+        return msg;
+    }
+
+    private announce(status = 'running'): void {
+        this.send(this.buildAnnounce(status));
+    }
+
+    private replyTo(rinfo: dgram.RemoteInfo): void {
+        const body = Buffer.from(JSON.stringify(this.buildAnnounce('running')));
+        try {
+            this.socket?.send(body, rinfo.port, rinfo.address);
+        } catch (e) {
+            console.warn('[meshdisco] Reply failed:', e);
+        }
+    }
+
+    /** Writes once per interface — the default route alone reaches one network. */
+    private send(msg: MeshMessage): void {
+        const socket = this.socket;
+        if (!socket) return;
+        const body = Buffer.from(JSON.stringify(msg));
+        for (const addr of this.ifaceAddrs) {
+            try {
+                socket.setMulticastInterface(addr);
+                socket.send(body, this.cfg.port, this.cfg.group);
+            } catch (e) {
+                console.warn(`[meshdisco] Send on ${addr} failed:`, e);
+            }
+        }
+    }
+}
+
+export interface MetaCoreLocatorConfig {
+    /** This service's name, for its own announce. */
+    serviceName: string;
+    /** Browser-facing URL for the nav menu. */
+    baseUrl?: string;
+    version?: string;
+    /**
+     * Explicit meta-core API URL. When set this ALWAYS wins and the wire is
+     * never consulted for core selection — see the spec's "the pin always
+     * wins". This is what stops a client box from latching onto a gateway
+     * box's core when both are reachable on a shared network.
+     */
+    metaCoreUrl?: string;
+    group?: string;
+    port?: number;
+    intervalMs?: number;
+    enabled?: boolean;
+}
+
+/**
+ * Locates meta-core over UDP, replacing the read of
+ * /meta-core/locks/kv-leader.info.
+ */
+export class MetaCoreLocator {
+    private node: MeshNode;
+    private cfg: MetaCoreLocatorConfig;
+    private current: MeshUrls | null = null;
+    private changeCallbacks: (() => void)[] = [];
+
+    constructor(config: MetaCoreLocatorConfig) {
+        this.cfg = config;
+        this.node = new MeshNode({
+            name: config.serviceName,
+            role: ROLE_SERVICE,
+            version: config.version,
+            group: config.group,
+            port: config.port,
+            intervalMs: config.intervalMs,
+            enabled: config.enabled,
+            payload: () => ({ baseUrl: config.baseUrl ?? `http://${localIPv4()}` }),
+        });
+
+        this.node.onAnnounce((nb) => {
+            if (nb.role !== ROLE_CORE || !nb.urls) return;
+            if (this.cfg.metaCoreUrl) return; // pinned: the wire cannot move us
+
+            const prev = this.current;
+            if (!prev) {
+                this.current = nb.urls;
+                console.log(`[meshdisco] meta-core discovered at ${nb.urls.apiUrl} (${nb.addr})`);
+                this.notifyChange();
+                return;
+            }
+            if (prev.apiUrl === nb.urls.apiUrl) {
+                this.current = nb.urls; // refresh the rest of the fields
+                return;
+            }
+            // A second, different core is announcing. Do not flap between
+            // them — keep the first and say so loudly, because on a PCS box
+            // this means a client container can see the gateway's core.
+            console.warn(
+                `[meshdisco] Ignoring a second meta-core at ${nb.urls.apiUrl} (${nb.addr}); ` +
+                `staying with ${prev.apiUrl}. Set META_CORE_URL to pin this explicitly.`
+            );
+        });
+    }
+
+    async start(): Promise<void> {
+        if (this.cfg.metaCoreUrl) {
+            console.log(`[meshdisco] meta-core pinned to ${this.cfg.metaCoreUrl}; discovery is advisory`);
+        }
+        await this.node.start();
+    }
+
+    async stop(): Promise<void> {
+        await this.node.stop();
+        this.changeCallbacks = [];
+    }
+
+    /** The pin if set, else whatever discovery elected. */
+    getApiUrl(): string | null {
+        if (this.cfg.metaCoreUrl) return this.cfg.metaCoreUrl;
+        return this.current?.apiUrl ?? null;
+    }
+
+    /** Full URLs block. null when pinned and /urls has not been fetched yet. */
+    getUrls(): MeshUrls | null {
+        return this.current;
+    }
+
+    /**
+     * Block until meta-core is located. Probes immediately and re-probes every
+     * 500ms — the same loop shape as the old LeaderClient.waitForLeader, so the
+     * 30s boot timeout semantics are preserved exactly.
+     */
+    async waitForCore(timeoutMs = 30_000): Promise<string> {
+        const deadline = Date.now() + timeoutMs;
+        let logged = false;
+        while (Date.now() < deadline) {
+            const url = this.getApiUrl();
+            if (url) return url;
+            if (!logged) { console.log('[meshdisco] Waiting for meta-core...'); logged = true; }
+            this.node.probe();
+            await new Promise((r) => setTimeout(r, 500));
+        }
+        throw new Error(`[meshdisco] No meta-core found within ${timeoutMs}ms`);
+    }
+
+    /** Fires when the elected core's apiUrl changes. Replaces the fs.watch. */
+    onChange(cb: () => void): void {
+        this.changeCallbacks.push(cb);
+    }
+
+    getNeighbors(): MeshNeighbor[] {
+        return this.node.getNeighborsByName();
+    }
+
+    self(): MeshNeighbor {
+        return this.node.self();
+    }
+
+    probe(): void {
+        this.node.probe();
+    }
+
+    private notifyChange(): void {
+        for (const cb of this.changeCallbacks) {
+            try { cb(); } catch (e) { console.error('[meshdisco] Change callback threw:', e); }
+        }
+    }
+}

packages/meta-sort-core/src/index.ts

@@ -125,22 +125,18 @@ process.on('SIGINT', async () => {
 // Start initial discovery and processing (streaming pipeline)
 (async () => {
     try {
-        // Validate META_CORE_PATH is configured (required for leader discovery)
+        // meta-core is located over UDP (meta-discovery v1) — no /meta-core
-        if (!config.META_CORE_PATH) {
+        // volume required. META_CORE_URL, when set, pins it and discovery
-            console.error('[Startup] ERROR: META_CORE_PATH is required. Set META_CORE_PATH environment variable.');
+        // never overrides; see docs/project-architecture/service-discovery.md.
-            console.error('[Startup] Example: META_CORE_PATH=/meta-core');
+        {
-            process.exit(1);
+            console.log('[Startup] Initializing KV Manager (meta-core discovery)...');
-        }
-
-        // Initialize KV Manager (Redis via leader discovery)
-        if (config.META_CORE_PATH) {
-            console.log('[Startup] Initializing KV Manager (leader discovery)...');
             kvManager = new KVManager({
                 metaCorePath: config.META_CORE_PATH,
                 filesPath: config.FILES_PATH,
                 serviceName: config.SERVICE_NAME,
                 apiPort: config.FUSE_API_PORT,
                 baseUrl: config.BASE_URL,
+                metaCoreUrl: config.META_CORE_URL,
             });
 
             // Wait for KV to be ready

packages/meta-sort-core/src/kv/IKVClient.ts

@@ -139,7 +139,7 @@ export interface KVClientConfig {
 }
 
 /**
- * Leader lock file content format (kv-leader.info)
+ * meta-core's identity and URL set (from its UDP announce, or /urls)
  * Written by meta-core leader, read by other services
  */
 export interface LeaderLockInfo {

packages/meta-sort-core/src/kv/KVManager.ts

@@ -2,13 +2,12 @@
  * KV Manager - Unified manager for KV storage and service discovery
  *
  * This is the main entry point for the KV subsystem. It:
- * 1. Uses LeaderClient to read leader info from meta-core
+ * 1. Uses LeaderClient to locate meta-core over UDP (meta-discovery v1)
  * 2. Creates and manages the KV client (Redis)
- * 3. Handles service discovery registration
  * 4. Manages reconnection on leader changes
  *
- * Note: Leader election is now handled by meta-core (Go sidecar).
+ * Note: there is no leader election. meta-core announces itself on the
- * This service only reads the leader info and connects to Redis.
+ * discovery group; this service listens and connects to its HTTP API.
  *
  * Usage:
  * ```typescript
@@ -28,7 +27,6 @@
 
 import { hostname } from 'os';
 import { LeaderClient } from './LeaderClient.js';
-import { ServiceRegistration } from './ServiceRegistration.js';
 import { RedisKVClient } from './RedisClient.js';
 import type { IKVClient, LeaderLockInfo } from './IKVClient.js';
 import { configure as configureWebdav } from '../webdav/WebdavClient.js';
@@ -59,7 +57,6 @@ interface KVManagerConfig {
 export class KVManager {
     private config: KVManagerConfig;
     private leaderClient: LeaderClient | null = null;
-    private serviceRegistration: ServiceRegistration | null = null;
     private kvClient: IKVClient | null = null;
     private isStarted = false;
     private isShuttingDown = false;
@@ -112,8 +109,14 @@ export class KVManager {
 
         // Initialize leader client
         this.leaderClient = new LeaderClient({
-            metaCorePath: this.config.metaCorePath,
+            metaCoreUrl: this.config.metaCoreUrl,
-            metaCoreUrl: this.config.metaCoreUrl
+            serviceName: this.config.serviceName,
+        // Browser-facing URL for the nav menu, in the order the spec requires:
+        // PUBLIC_URL (reachable when there is no Caddy perimeter in front — a
+        // debug-direct port) -> BASE_URL (the Caddy URL) -> container host.
+        // Announcing a Caddy URL on a stack with no Caddy running is what puts
+        // dead links in every neighbour's menu.
+            baseUrl: process.env.PUBLIC_URL || this.config.baseUrl || `http://${hostname()}:${this.config.apiPort}`,
         });
 
         // Watch for leader changes
@@ -149,15 +152,9 @@ export class KVManager {
         // Start watching for leader changes
         this.leaderClient.startWatching();
 
-        // Initialize and start service registration for heartbeat
+        // No separate service registration step any more: the LeaderClient's
-        const apiUrl = this.config.baseUrl || `http://${hostname()}:${this.config.apiPort}`;
+        // discovery node announces this service on the same UDP group it
-        this.serviceRegistration = new ServiceRegistration({
+        // listens on, so being discoverable and discovering are one thing.
-            metaCorePath: this.config.metaCorePath,
-            serviceName: this.config.serviceName,
-            version: '1.0.0',
-            apiUrl
-        });
-        await this.serviceRegistration.start();
 
         this.isStarted = true;
         this.notifyReady();
@@ -224,10 +221,6 @@ export class KVManager {
         }
 
         // Service registration stop (if it was started)
-        if (this.serviceRegistration) {
-            await this.serviceRegistration.stop();
-            this.serviceRegistration = null;
-        }
 
         this.isStarted = false;
         console.log('[KVManager] Stopped');
@@ -324,9 +317,6 @@ export class KVManager {
     /**
      * Get service registration instance
      */
-    getServiceRegistration(): ServiceRegistration | null {
-        return this.serviceRegistration;
-    }
 
     /**
      * Check if the KV store is healthy

packages/meta-sort-core/src/kv/LeaderClient.ts

@@ -1,26 +1,48 @@
 /**
- * LeaderClient - Client for reading leader info from meta-core
+ * LeaderClient - locates meta-core and exposes its URLs.
  *
- * This replaces the old LeaderElection.ts by delegating leader election
+ * Since meta-discovery v1 this is a thin adapter over MetaCoreLocator
- * to meta-core (Go sidecar) and just reading the results.
+ * (../discovery/meshdisco.js): meta-core is found by UDP announce instead of by
+ * reading /meta-core/locks/kv-leader.info, which means this service no longer
+ * needs the /meta-core volume mounted at all.
  *
- * Features:
+ * The public surface is deliberately unchanged so KVManager and its callers did
- * - Reads kv-leader.info file for leader URLs
+ * not have to move:
- * - Calls meta-core /urls API for current leader URLs
+ * - getLeaderInfo() / getUrls() / getApiUrl() / getWebdavUrl*()
- * - Watches for leader changes via file system watcher
+ * - waitForLeader(timeoutMs)   — same 30s default, same "poll until it answers"
+ * - startWatching() / onChange() — the fs.watch on the lock dir became "an
+ *   announce arrived carrying a different apiUrl", feeding the same callback.
+ *
+ * Precedence is the pin: when metaCoreUrl (META_CORE_URL) is set it always
+ * wins and the wire is never consulted for core selection. See
+ * docs/project-architecture/service-discovery.md.
+ *
+ * The name "leader" is legacy. meta-core's flock election is vestigial — the Go
+ * binary only ever runs as leader — and redisUrl has been empty since the
+ * api-mediated-access lockdown; everything routes over HTTP.
  */
 
-import { promises as fs } from 'fs';
+import { MetaCoreLocator, type MeshNeighbor } from '../discovery/meshdisco.js';
-import { watch, FSWatcher } from 'fs';
-import { dirname } from 'path';
 import type { LeaderLockInfo } from './IKVClient.js';
 
 export interface LeaderClientConfig {
-    /** Path to META_CORE_VOLUME (e.g., /meta-core) */
+    /**
-    metaCorePath: string;
+     * @deprecated Unused since meta-discovery v1. Kept so existing callers
+     * compile unchanged; nothing reads the volume any more.
+     */
+    metaCorePath?: string;
 
-    /** meta-core API URL (e.g., http://meta-core:9000 or http://localhost:9000) */
+    /** meta-core API URL. When set, discovery never overrides it. */
     metaCoreUrl?: string;
+
+    /** This service's name, used for its own announce. */
+    serviceName?: string;
+
+    /** Browser-facing URL announced for the nav menu. */
+    baseUrl?: string;
+
+    /** Service version, display only. */
+    version?: string;
 }
 
 export interface URLsResponse {
@@ -35,76 +57,79 @@ export interface URLsResponse {
 
 export class LeaderClient {
     private config: LeaderClientConfig;
-    private infoFilePath: string;
+    private locator: MetaCoreLocator;
     private leaderInfo: LeaderLockInfo | null = null;
-    private watcher: FSWatcher | null = null;
     private onChangeCallbacks: (() => void)[] = [];
+    private started = false;
 
-    // URL caching
+    // URL caching — only used on the pinned path, where the URLs still come
+    // from an HTTP GET /urls. A discovered core carries them in the announce.
     private cachedUrls: URLsResponse | null = null;
-    private urlsCacheTime: number = 0;
+    private urlsCacheTime = 0;
-    private readonly urlsCacheTTL: number = 5000; // 5 seconds
+    private readonly urlsCacheTTL = 5000;
 
     constructor(config: LeaderClientConfig) {
         this.config = config;
-        this.infoFilePath = `${config.metaCorePath}/locks/kv-leader.info`;
+        this.locator = new MetaCoreLocator({
-    }
+            serviceName: config.serviceName ?? 'meta-sort',
-
+            baseUrl: config.baseUrl,
-    /**
+            version: config.version,
-     * Read API URL from file (plain text format)
+            metaCoreUrl: config.metaCoreUrl,
-     */
+            enabled: process.env.ENABLE_UDP_DISCOVERY !== 'false' &&
-    private async getApiUrlFromFile(): Promise<string | null> {
+                process.env.ENABLE_UDP_DISCOVERY !== '0',
-        try {
+        });
-            const content = await fs.readFile(this.infoFilePath, 'utf-8');
+        this.locator.onChange(() => {
-            return content.trim() || null;
+            this.cachedUrls = null;
-        } catch (error) {
+            this.urlsCacheTime = 0;
-            console.error('[LeaderClient] Failed to read API URL from file:', error);
+            this.notifyChange();
-            return null;
-        }
-    }
-
-    /**
-     * Fetch URLs from meta-core /urls API with caching
-     */
-    private async fetchUrls(apiUrl: string): Promise<URLsResponse | null> {
-        // Check cache
-        const now = Date.now();
-        if (this.cachedUrls && (now - this.urlsCacheTime) < this.urlsCacheTTL) {
-            return this.cachedUrls;
-        }
-
-        try {
-            const response = await fetch(`${apiUrl}/urls`, {
-                method: 'GET',
-                headers: { 'Accept': 'application/json' },
-                signal: AbortSignal.timeout(5000)
         });
-
-            if (!response.ok) {
-                console.error('[LeaderClient] Failed to fetch URLs:', response.status, response.statusText);
-                return null;
     }
 
-            const parsed = await response.json() as URLsResponse;
+    /** Idempotent; safe to call from any entry point. */
-            // api-mediated-access PR D: redisUrl is no longer published by
+    private async ensureStarted(): Promise<void> {
-            // meta-core. If it shows up, an older build snuck back in —
+        if (this.started) return;
-            // fail loudly so the rollback can't go unnoticed. Set
+        this.started = true;
-            // ALLOW_LEGACY_REDIS_URL=1 to downgrade to a warning during a
+        await this.locator.start();
-            // deliberate temporary rollback.
+    }
-            if (parsed.redisUrl) {
+
+    /**
+     * Guard against a rollback that reintroduces direct Redis exposure.
+     * api-mediated-access PR D removed redisUrl; if it comes back, fail loudly
+     * so it can't go unnoticed. ALLOW_LEGACY_REDIS_URL=1 downgrades to a warn.
+     */
+    private assertNoRedisUrl(redisUrl: string | undefined): void {
+        if (!redisUrl) return;
         const msg =
-                    '[LeaderClient] meta-core still publishes redisUrl; ' +
+            '[LeaderClient] meta-core still publishes redisUrl; direct Redis access ' +
-                    'direct Redis access was retired by the api-mediated-access ' +
+            'was retired by the api-mediated-access lockdown. Verify meta-core version.';
-                    'lockdown. Verify meta-core version.';
         if (process.env.ALLOW_LEGACY_REDIS_URL === '1') {
             console.warn('WARNING: ' + msg);
         } else {
             throw new Error(msg);
         }
     }
+
+    /** HTTP GET {apiUrl}/urls — still needed when meta-core is pinned. */
+    private async fetchUrls(apiUrl: string): Promise<URLsResponse | null> {
+        const now = Date.now();
+        if (this.cachedUrls && now - this.urlsCacheTime < this.urlsCacheTTL) {
+            return this.cachedUrls;
+        }
+        try {
+            const response = await fetch(`${apiUrl}/urls`, {
+                method: 'GET',
+                headers: { Accept: 'application/json' },
+                signal: AbortSignal.timeout(5000),
+            });
+            if (!response.ok) {
+                console.error('[LeaderClient] Failed to fetch URLs:', response.status, response.statusText);
+                return null;
+            }
+            const parsed = (await response.json()) as URLsResponse;
+            this.assertNoRedisUrl(parsed.redisUrl);
             this.cachedUrls = parsed;
             this.urlsCacheTime = now;
-            return this.cachedUrls;
+            return parsed;
         } catch (error) {
             console.error('[LeaderClient] Error calling /urls API:', error);
             return null;
@@ -112,23 +137,37 @@ export class LeaderClient {
     }
 
     /**
-     * Read leader info from file and /urls API
+     * Resolve meta-core's URLs — from the announce when discovered (no HTTP
+     * hop needed, the payload already carries them), or over HTTP when pinned.
      */
+    async getUrls(): Promise<URLsResponse | null> {
+        await this.ensureStarted();
+
+        const wire = this.locator.getUrls();
+        if (wire && !this.config.metaCoreUrl) {
+            return {
+                hostname: wire.hostname,
+                baseUrl: wire.baseUrl,
+                apiUrl: wire.apiUrl,
+                redisUrl: '',
+                webdavUrl: wire.webdavUrl,
+                webdavUrlInternal: wire.webdavUrlInternal,
+                isLeader: true,
+            };
+        }
+
+        const apiUrl = this.locator.getApiUrl();
+        if (!apiUrl) {
+            console.error('[LeaderClient] No meta-core API URL available');
+            return null;
+        }
+        return this.fetchUrls(apiUrl);
+    }
+
     async getLeaderInfo(): Promise<LeaderLockInfo | null> {
         try {
-            // Read API URL from file (plain text)
+            const urls = await this.getUrls();
-            const apiUrl = await this.getApiUrlFromFile();
+            if (!urls) return null;
-            if (!apiUrl) {
-                return null;
-            }
-
-            // Fetch full info from /urls API
-            const urls = await this.fetchUrls(apiUrl);
-            if (!urls) {
-                return null;
-            }
-
-            // Convert URLsResponse to LeaderLockInfo
             this.leaderInfo = {
                 hostname: urls.hostname,
                 baseUrl: urls.baseUrl,
@@ -137,7 +176,7 @@ export class LeaderClient {
                 webdavUrl: urls.webdavUrl,
                 webdavUrlInternal: urls.webdavUrlInternal,
                 timestamp: Date.now(),
-                pid: 0 // Unknown for remote leader
+                pid: 0,
             };
             return this.leaderInfo;
         } catch (error) {
@@ -146,134 +185,67 @@ export class LeaderClient {
         }
     }
 
-    /**
-     * Get Redis URL from leader info
-     */
     async getRedisUrl(): Promise<string | null> {
-        const info = await this.getLeaderInfo();
+        return (await this.getLeaderInfo())?.redisUrl ?? null;
-        return info?.redisUrl ?? null;
     }
 
-    /**
-     * Get WebDAV URL from leader info (external, via nginx/HTTPS)
-     */
     async getWebdavUrl(): Promise<string | null> {
-        const info = await this.getLeaderInfo();
+        return (await this.getLeaderInfo())?.webdavUrl ?? null;
-        return info?.webdavUrl ?? null;
     }
 
-    /**
+    /** Internal WebDAV URL — use for container-to-container access. */
-     * Get internal WebDAV URL from leader info (direct to port 9000)
-     * Use this for container-to-container communication
-     */
     async getWebdavUrlInternal(): Promise<string | null> {
-        const info = await this.getLeaderInfo();
+        return (await this.getLeaderInfo())?.webdavUrlInternal ?? null;
-        return info?.webdavUrlInternal ?? null;
     }
 
-    /**
-     * Get meta-core API URL from leader info
-     */
     async getApiUrl(): Promise<string | null> {
-        const info = await this.getLeaderInfo();
+        return (await this.getLeaderInfo())?.apiUrl ?? null;
-        return info?.apiUrl ?? null;
     }
 
     /**
-     * Call meta-core /urls API to get current URLs
+     * Block until meta-core is reachable. Probes immediately then every 500ms,
-     * Useful for getting URLs when you don't want to read the file directly
+     * matching the previous file-polling loop's timing exactly.
-     */
-    async getUrls(): Promise<URLsResponse | null> {
-        // First try using configured metaCoreUrl
-        let apiUrl = this.config.metaCoreUrl;
-
-        // Fall back to reading from file
-        if (!apiUrl) {
-            apiUrl = await this.getApiUrlFromFile();
-        }
-
-        if (!apiUrl) {
-            console.error('[LeaderClient] No meta-core API URL available');
-            return null;
-        }
-
-        return this.fetchUrls(apiUrl);
-    }
-
-    /**
-     * Wait for leader info to be available
      */
     async waitForLeader(timeoutMs: number = 30000): Promise<LeaderLockInfo> {
-        const startTime = Date.now();
+        await this.ensureStarted();
-        const pollInterval = 500;
+        const deadline = Date.now() + timeoutMs;
 
-        while (Date.now() - startTime < timeoutMs) {
+        // Locate the core (pin returns instantly; discovery probes).
+        await this.locator.waitForCore(timeoutMs);
+
+        // Then wait for a usable URLs payload — on the pinned path this is the
+        // first successful GET /urls, so meta-core still has to be up.
+        while (Date.now() < deadline) {
             const info = await this.getLeaderInfo();
             if (info) {
-                console.log(`[LeaderClient] Leader found: ${info.hostname} at ${info.redisUrl}`);
+                console.log(`[LeaderClient] meta-core found: ${info.hostname} at ${info.apiUrl}`);
                 return info;
             }
-
+            console.log('[LeaderClient] Waiting for meta-core...');
-            console.log('[LeaderClient] Waiting for leader...');
+            await new Promise((resolve) => setTimeout(resolve, 500));
-            await new Promise(resolve => setTimeout(resolve, pollInterval));
         }
-
+        throw new Error(`No meta-core found within ${timeoutMs}ms`);
-        throw new Error(`No leader found within ${timeoutMs}ms`);
     }
 
     /**
-     * Start watching for leader changes
+     * Previously an fs.watch on the lock directory. Discovery is always
+     * listening, so this only has to make sure the node is running.
      */
     startWatching(): void {
-        if (this.watcher) {
+        void this.ensureStarted();
-            return; // Already watching
     }
 
-        const lockDir = dirname(this.infoFilePath);
-
-        try {
-            this.watcher = watch(lockDir, (eventType, filename) => {
-                if (filename === 'kv-leader.info') {
-                    console.log('[LeaderClient] Leader info changed, invalidating cache...');
-                    // Invalidate cache to force fresh API call
-                    this.cachedUrls = null;
-                    this.urlsCacheTime = 0;
-
-                    this.getLeaderInfo().then(() => {
-                        this.notifyChange();
-                    }).catch(console.error);
-                }
-            });
-
-            console.log(`[LeaderClient] Watching for leader changes in ${lockDir}`);
-        } catch (error) {
-            console.error('[LeaderClient] Failed to start watching:', error);
-        }
-    }
-
-    /**
-     * Stop watching for leader changes
-     */
     stopWatching(): void {
-        if (this.watcher) {
+        // No-op: the locator keeps listening until close().
-            this.watcher.close();
-            this.watcher = null;
-            console.log('[LeaderClient] Stopped watching for leader changes');
-        }
     }
 
-    /**
-     * Register callback for leader changes
-     */
     onChange(callback: () => void): this {
         this.onChangeCallbacks.push(callback);
         return this;
     }
 
-    /**
-     * Notify all change callbacks
-     */
     private notifyChange(): void {
+        console.log('[LeaderClient] meta-core changed, invalidating cache...');
         for (const callback of this.onChangeCallbacks) {
             try {
                 callback();
@@ -283,18 +255,23 @@ export class LeaderClient {
         }
     }
 
-    /**
-     * Get cached leader info (without re-reading file)
-     */
     getCachedLeaderInfo(): LeaderLockInfo | null {
         return this.leaderInfo;
     }
 
-    /**
+    /** Neighbours for the nav menu (one row per service name). */
-     * Clean up resources
+    getNeighbors(): MeshNeighbor[] {
-     */
+        return this.locator.getNeighbors();
+    }
+
+    /** This service's own announce, so the menu can show itself. */
+    self(): MeshNeighbor {
+        return this.locator.self();
+    }
+
     close(): void {
-        this.stopWatching();
         this.onChangeCallbacks = [];
+        void this.locator.stop();
+        this.started = false;
     }
 }

packages/meta-sort-core/src/kv/MetaCoreApiWriter.ts

@@ -19,6 +19,24 @@ import {
     buildFilePrefix,
 } from './MetadataUtils.js';
 
+/** One file-backed root as listed by meta-core's GET /api/files/tuples. */
+export interface FileTuple {
+    hashId: string;
+    filePath: string;
+    sizeByte: number;
+    mtimeNano: number;
+}
+
+/**
+ * GET /api/files/tuples body. `files` is present unless the summary form was
+ * asked for.
+ */
+export interface FileTuplesResult {
+    count: number;
+    totalSize: number;
+    files?: FileTuple[];
+}
+
 export interface MetaCoreApiWriterConfig {
     /** Base URL for meta-core's HTTP API (e.g. http://metacore-app:9000) */
     apiUrl: string;
@@ -139,6 +157,27 @@ export class MetaCoreApiWriter {
         return Array.isArray(ids) ? ids : [];
     }
 
+    /**
+     * GET /api/files/tuples. meta-core's FILE-BACKED roots (records carrying
+     * filePath, sizeByte and mtimeNano) with sizes, read server-side in batched
+     * MGETs — the cheap alternative to walking getAllHashIds(), which on a
+     * shared meta-core is every gateway record too. `summary` omits the rows.
+     *
+     * Returns null when meta-core predates the endpoint (404, or a body that is
+     * not the expected JSON).
+     */
+    async getFileTuples(opts: { summary?: boolean } = {}): Promise<FileTuplesResult | null> {
+        const path = opts.summary ? '/api/files/tuples?summary=1' : '/api/files/tuples';
+        const body = await this.fetchJsonAllowing404('GET', path);
+        if (!body || typeof body !== 'object') return null;
+        const b = body as { count?: unknown; totalSize?: unknown; files?: unknown };
+        return {
+            count: Number(b.count) || 0,
+            totalSize: Number(b.totalSize) || 0,
+            files: Array.isArray(b.files) ? (b.files as FileTuple[]) : undefined,
+        };
+    }
+
     /**
      * GET /health on meta-core. Used as a write-path health probe.
      */

packages/meta-sort-core/src/kv/RedisClient.ts

@@ -21,7 +21,7 @@ import {
     buildFilePrefix,
     buildPropertyKey,
 } from './MetadataUtils.js';
-import { MetaCoreApiWriter } from './MetaCoreApiWriter.js';
+import { MetaCoreApiWriter, type FileTuplesResult } from './MetaCoreApiWriter.js';
 
 // ESM/CJS interop for ioredis
 const Redis = (IORedis as any).default ?? IORedis;
@@ -102,7 +102,22 @@ export class RedisKVClient implements IKVClient {
             // automatic connect. Any caller that tries to use the Redis
             // path (e.g. unmigrated stream code) will fail loudly rather
             // than silently misbehaving.
-            this.redis = new Redis({ host: '127.0.0.1', port: 0, lazyConnect: true, enableOfflineQueue: false });
+            this.redis = new Redis({
+                host: '127.0.0.1',
+                port: 0,
+                lazyConnect: true,
+                enableOfflineQueue: false,
+                // Never reconnect. A stub that retries turns one stray call into
+                // an endless "Unhandled error event: ECONNREFUSED" loop.
+                retryStrategy: () => null,
+                maxRetriesPerRequest: 0,
+            });
+            let stubWarned = false;
+            this.redis.on('error', (err: Error) => {
+                if (stubWarned) return;
+                stubWarned = true;
+                console.warn(`[Redis] HTTP-only stub was used and refused (${err.message}) — a caller still reaches for direct Redis`);
+            });
             this.isConnected = false;
             console.log('[Redis] HTTP-only mode — no direct Redis connection');
             return;
@@ -474,6 +489,15 @@ export class RedisKVClient implements IKVClient {
         return await this.redis.smembers(indexKey);
     }
 
+    /**
+     * File-backed roots from meta-core (GET /api/files/tuples). Only the HTTP
+     * writer can serve this; direct-Redis mode returns null so callers take
+     * their degraded path instead of sweeping every record.
+     */
+    async getFileTuples(opts: { summary?: boolean } = {}): Promise<FileTuplesResult | null> {
+        return this.writer ? this.writer.getFileTuples(opts) : null;
+    }
+
     // ========================================================================
     // Pub/Sub Operations
     // ========================================================================

packages/meta-sort-core/src/kv/ServiceRegistration.ts

@@ -1,199 +0,0 @@
-/**
- * Service Registration using shared filesystem
- *
- * Each service registers itself in /meta-core/services/{service-name}-{hostname}.json
- * with its base URL, status, and heartbeat timestamp.
- *
- * Service discovery is centralized in meta-core - this class only handles registration.
- * For service discovery, use the /api/services endpoint (proxied to meta-core via nginx).
- *
- * Each service must call start() to register itself and begin heartbeat updates.
- * meta-core runs a cleanup process that removes services with stale heartbeats.
- */
-
-import { promises as fs } from 'fs';
-import { hostname } from 'os';
-import type { ServiceInfo } from './IKVClient.js';
-import { isNodeError } from '../types/ExtendedInterfaces.js';
-
-interface ServiceRegistrationConfig {
-    /** Path to META_CORE_VOLUME (e.g., /meta-core) */
-    metaCorePath: string;
-
-    /** Service name */
-    serviceName: string;
-
-    /** Service version (optional, not used in simplified format) */
-    version?: string;
-
-    /** Base URL for the service */
-    apiUrl: string;
-
-    /** Heartbeat interval in ms (default: 30000) */
-    heartbeatInterval?: number;
-
-    /** Stale threshold in ms (default: 60000) */
-    staleThreshold?: number;
-}
-
-export class ServiceRegistration {
-    private config: ServiceRegistrationConfig;
-    private servicesDir: string;
-    private serviceFilePath: string;
-    private heartbeatTimer: NodeJS.Timeout | null = null;
-    private isShuttingDown = false;
-    private currentHostname: string;
-
-    constructor(config: ServiceRegistrationConfig) {
-        this.config = {
-            heartbeatInterval: 30000,
-            staleThreshold: 60000,
-            ...config
-        };
-
-        this.currentHostname = hostname();
-        this.servicesDir = `${this.config.metaCorePath}/services`;
-        // Use hostname-based file naming
-        this.serviceFilePath = `${this.servicesDir}/${this.config.serviceName}-${this.currentHostname}.json`;
-    }
-
-    /**
-     * Ensure services directory exists
-     */
-    private async ensureServicesDir(): Promise<void> {
-        await fs.mkdir(this.servicesDir, { recursive: true });
-    }
-
-    /**
-     * Build service info for this service
-     */
-    private buildServiceInfo(status: ServiceInfo['status']): ServiceInfo {
-        return {
-            name: this.config.serviceName,
-            hostname: this.currentHostname,
-            baseUrl: this.config.apiUrl,
-            status,
-            lastHeartbeat: new Date().toISOString()
-        };
-    }
-
-    /**
-     * Register this service by writing service info to the shared filesystem.
-     * meta-core's cleanup process monitors these files and removes stale entries.
-     */
-    async register(): Promise<void> {
-        await this.ensureServicesDir();
-
-        const info = this.buildServiceInfo('running');
-        await fs.writeFile(this.serviceFilePath, JSON.stringify(info, null, 2));
-
-        console.log(`[ServiceRegistration] Registered ${this.config.serviceName}-${this.currentHostname}`);
-    }
-
-    /**
-     * Update service status
-     */
-    async updateStatus(status: ServiceInfo['status']): Promise<void> {
-        try {
-            const content = await fs.readFile(this.serviceFilePath, 'utf-8');
-            const info = JSON.parse(content) as ServiceInfo;
-
-            info.status = status;
-            info.lastHeartbeat = new Date().toISOString();
-
-            await fs.writeFile(this.serviceFilePath, JSON.stringify(info, null, 2));
-        } catch (error) {
-            console.error('[ServiceRegistration] Failed to update status:', error);
-        }
-    }
-
-    /**
-     * Send heartbeat (update lastHeartbeat timestamp)
-     */
-    async heartbeat(): Promise<void> {
-        try {
-            const content = await fs.readFile(this.serviceFilePath, 'utf-8');
-            const info = JSON.parse(content) as ServiceInfo;
-
-            info.lastHeartbeat = new Date().toISOString();
-
-            await fs.writeFile(this.serviceFilePath, JSON.stringify(info, null, 2));
-        } catch (error) {
-            // If file was deleted, re-register
-            if (isNodeError(error) && error.code === 'ENOENT') {
-                await this.register();
-            } else {
-                console.error('[ServiceRegistration] Heartbeat failed:', error);
-            }
-        }
-    }
-
-    /**
-     * Start heartbeat loop
-     */
-    startHeartbeat(): void {
-        this.heartbeatTimer = setInterval(async () => {
-            if (this.isShuttingDown) return;
-            await this.heartbeat();
-        }, this.config.heartbeatInterval);
-    }
-
-    /**
-     * Stop heartbeat loop
-     */
-    stopHeartbeat(): void {
-        if (this.heartbeatTimer) {
-            clearInterval(this.heartbeatTimer);
-            this.heartbeatTimer = null;
-        }
-    }
-
-    /**
-     * Unregister this service (on shutdown)
-     */
-    async unregister(): Promise<void> {
-        this.isShuttingDown = true;
-        this.stopHeartbeat();
-
-        try {
-            // Remove the service file
-            await fs.unlink(this.serviceFilePath);
-            console.log(`[ServiceRegistration] Unregistered ${this.config.serviceName}-${this.currentHostname}`);
-        } catch (error) {
-            if (!isNodeError(error) || error.code !== 'ENOENT') {
-                console.error('[ServiceRegistration] Failed to unregister:', error);
-            }
-        }
-    }
-
-    // ========================================================================
-    // Lifecycle
-    // ========================================================================
-
-    /**
-     * Full startup sequence: register service and start heartbeat loop.
-     */
-    async start(): Promise<void> {
-        await this.register();
-        this.startHeartbeat();
-    }
-
-    /**
-     * Full shutdown sequence
-     */
-    async stop(): Promise<void> {
-        await this.unregister();
-    }
-
-    // ========================================================================
-    // Getters
-    // ========================================================================
-
-    getServiceFilePath(): string {
-        return this.serviceFilePath;
-    }
-
-    getServicesDir(): string {
-        return this.servicesDir;
-    }
-}

packages/meta-sort-core/src/kv/index.ts

@@ -5,7 +5,8 @@
  * - IKVClient interface for KV storage abstraction
  * - RedisKVClient for Redis-based storage
  * - LeaderClient for reading leader info from meta-core
- * - ServiceRegistration for service registration (discovery is centralized in meta-core)
+ * Services announce and discover over UDP (meta-discovery v1); there is no
+ * separate registration step, so no ServiceRegistration export.
  * - KVManager for unified management of all components
  * - MetadataUtils for flattening/reconstructing nested metadata
  */
@@ -13,6 +14,5 @@
 export * from './IKVClient.js';
 export * from './RedisClient.js';
 export * from './LeaderClient.js';
-export * from './ServiceRegistration.js';
 export * from './KVManager.js';
 export * from './MetadataUtils.js';

packages/meta-sort-core/src/logic/MetadataFormatRegistry.ts

@@ -85,13 +85,10 @@ export class JellyfinFormatHandler implements IMetadataFormatHandler {
         if (metadata.originalTitle) jellyfinFields.originalTitle = metadata.originalTitle;
         if (metadata.movieYear) jellyfinFields.year = metadata.movieYear;
 
-        // Titles (first title or original title)
+        // Title: the display name. `titles/*` is an unordered name set with no
-        if (metadata.titles) {
+        // preferred member, so it is never the NFO title (METADATA_KEYS.md §3).
-            const titleEntries = Object.entries(metadata.titles);
+        const title = metadata.title || metadata.originalTitle;
-            if (titleEntries.length > 0) {
+        if (title) jellyfinFields.title = title;
-                jellyfinFields.title = titleEntries[0][1];
-            }
-        }
 
         // IDs
         if (metadata.imdbid) jellyfinFields.imdbid = metadata.imdbid;

packages/meta-sort-core/src/logic/UnifiedProcessingStateManager.ts

@@ -195,6 +195,16 @@ export class UnifiedProcessingStateManager {
       performanceMetrics.recordHashProcessing(hashProcessingTime);
     }
 
+    // File-level metric, one per file that finished cleanly. Nothing recorded
+    // it before, so the monitor's "Processed" tile stayed at 0. Files announced
+    // over SSE are never marked discovered, so fall back to the light phase.
+    if (!error) {
+      const fileTime = totalProcessingTime
+        ?? (hashState?.lightProcessingStartedAt !== undefined ? now - hashState.lightProcessingStartedAt : hashProcessingTime)
+        ?? 0;
+      performanceMetrics.recordFileProcessing(filePath, fileTime);
+    }
+
     const doneState: UnifiedFileState = {
       filePath,
       state: 'done',

packages/meta-sort-core/src/types/ExtendedInterfaces.ts

@@ -8,6 +8,7 @@
 
 import type { HashMeta } from '@metazla/meta-interface';
 import type { IKVClient } from '../kv/IKVClient.js';
+import type { FileTuplesResult } from '../kv/MetaCoreApiWriter.js';
 import type { FileAnalyzerInterface } from '../logic/fileProcessor/FileAnalyzerInterface.js';
 import type { ContainerTask } from '../container-plugins/types.js';
 import type { UnifiedProcessingSnapshot } from '../logic/UnifiedProcessingStateManager.js';
@@ -41,6 +42,21 @@ export function hasPublish(client: IKVClient): client is IKVClientWithPubSub {
     return typeof (client as IKVClientWithPubSub).publish === 'function';
 }
 
+/**
+ * IKVClient that can list meta-core's file-backed roots in one call
+ * (GET /api/files/tuples). Resolves null when meta-core predates the endpoint.
+ */
+export interface IKVClientWithFileTuples extends IKVClient {
+    getFileTuples(opts?: { summary?: boolean }): Promise<FileTuplesResult | null>;
+}
+
+/**
+ * Type guard to check if a KVClient can list file-backed roots
+ */
+export function hasFileTuples(client: IKVClient): client is IKVClientWithFileTuples {
+    return typeof (client as IKVClientWithFileTuples).getFileTuples === 'function';
+}
+
 /**
  * IKVClient with Redis Streams capabilities
  *

packages/meta-sort-editor/src/types/index.ts

@@ -9,7 +9,7 @@ export interface FileMetadata {
 
   // Filename parsing
   title?: string;
-  titles?: string[];
+  titles?: Record<string, Record<string, true | string>>; // key-set: lang3 → {name: "true"}
   originaltitle?: string;
   showtitle?: string;
   season?: number;

packages/meta-sort-ui/src/components/ServiceNav.tsx

@@ -1,164 +1,53 @@
-import { useState, useEffect } from 'react';
+import { useEffect } from 'react';
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore -- plain ES module, no .d.ts; imported for its side effect
+// of defining the custom element.
+import '../meta-service-menu.js';
 
-interface ServiceInfo {
+/**
-  name: string;
+ * ServiceNav — the neighbouring meta-* services, as a burger menu.
-  hostname: string;
+ *
-  baseUrl: string;
+ * Since meta-discovery v1 this is a thin wrapper around <meta-service-menu>,
-  status: string;
+ * a framework-free custom element shared by every meta-* UI (see
-  lastHeartbeat: string;
+ * scripts/check-mirrors.sh). The old implementation was ~165 lines of React
+ * that existed in four near-identical copies and polled meta-core's
+ * /api/services; the element polls this service's own /api/neighbors instead,
+ * so the nav still renders when meta-core is down.
+ *
+ * The element lives in shadow DOM and cannot see this app's CSS variables, so
+ * the four --mm-nav-* tokens below map our palette onto it.
+ */
+
+declare global {
+    // eslint-disable-next-line @typescript-eslint/no-namespace
+    namespace JSX {
+        interface IntrinsicElements {
+            'meta-service-menu': React.DetailedHTMLProps<
+                React.HTMLAttributes<HTMLElement>,
+                HTMLElement
+            > & { current?: string; endpoint?: string; label?: string };
         }
-
-interface ServicesResponse {
-  services: ServiceInfo[];
-  current: string;
     }
-
-const serviceIcons: Record<string, string> = {
-  'meta-sort': '📁',
-  'meta-fuse': '🗂️',
-  'meta-stremio': '🎬',
-  'meta-core': '⚙️',
-  'meta-dup': '🔍',
-  'meta-orbit': '🌐',
-  'default': '📦'
-};
-
-function formatServiceName(name: string): string {
-  return name.split('-').map(word =>
-    word.charAt(0).toUpperCase() + word.slice(1)
-  ).join(' ');
 }
 
 function ServiceNav() {
-  const [services, setServices] = useState<ServiceInfo[]>([]);
-  const [loading, setLoading] = useState(true);
-  const currentService = 'meta-sort';
-
     useEffect(() => {
-    const fetchServices = async () => {
+        // Import above is for the side effect of defining the element; this
-      try {
+        // keeps bundlers from tree-shaking it away in production builds.
-        const response = await fetch('/api/services');
-        if (response.ok) {
-          const data: ServicesResponse = await response.json();
-          setServices(data.services || []);
-        }
-      } catch (error) {
-        console.error('Failed to fetch services:', error);
-      } finally {
-        setLoading(false);
-      }
-    };
-
-    fetchServices();
-    const interval = setInterval(fetchServices, 30000);
-    return () => clearInterval(interval);
     }, []);
 
-  if (loading) return null;
-
-  const sortedServices = [...services].sort((a, b) => a.name.localeCompare(b.name));
-
-  if (sortedServices.length === 0) return null;
-
     return (
-    <nav className="services-nav">
+        <>
-      <span className="services-nav-label">Services:</span>
+            <meta-service-menu current="meta-sort" />
-      <div className="services-nav-items">
-        {sortedServices.map(service => {
-          const icon = serviceIcons[service.name] || serviceIcons.default;
-          const isActive = service.name === currentService;
-          return (
-            <a
-              key={service.name}
-              href={isActive ? '#' : service.baseUrl}
-              className={`service-link${isActive ? ' active' : ''}`}
-              onClick={(e) => {
-                e.preventDefault();
-                if (!isActive) {
-                  window.location.href = service.baseUrl;
-                }
-              }}
-            >
-              <span className="service-icon">{icon}</span>
-              <span>{formatServiceName(service.name)}</span>
-              <span className="service-status"></span>
-            </a>
-          );
-        })}
-      </div>
-
             <style>{`
-        .services-nav {
+                meta-service-menu {
-          background: var(--bg-secondary);
+                    --mm-nav-fg: var(--text-primary, #e0e0e0);
-          border-radius: 12px;
+                    --mm-nav-bg: var(--bg-tertiary, var(--bg-secondary, #1a1a2e));
-          padding: 0.5rem;
+                    --mm-nav-border: var(--border-color, rgba(255,255,255,0.14));
-          margin-bottom: 1.5rem;
+                    --mm-nav-accent: var(--accent-primary, #4ecdc4);
-          display: flex;
-          align-items: center;
-          gap: 0.5rem;
-          flex-wrap: wrap;
-          border: 1px solid var(--border-color);
-        }
-
-        .services-nav-label {
-          color: var(--text-secondary);
-          font-size: 0.85rem;
-          padding: 0.5rem 0.75rem;
-          white-space: nowrap;
-        }
-
-        .services-nav-items {
-          display: flex;
-          gap: 0.5rem;
-          flex-wrap: wrap;
-        }
-
-        .service-link {
-          display: inline-flex;
-          align-items: center;
-          gap: 0.4rem;
-          padding: 0.5rem 1rem;
-          border-radius: 8px;
-          text-decoration: none;
-          font-size: 0.9rem;
-          font-weight: 500;
-          transition: all 0.2s;
-          color: var(--text-primary);
-          background: var(--bg-tertiary);
-          border: 1px solid var(--border-color);
-        }
-
-        .service-link:hover {
-          background: var(--border-color);
-          border-color: rgba(78, 205, 196, 0.5);
-          text-decoration: none;
-        }
-
-        .service-link.active {
-          background: linear-gradient(135deg, rgba(78, 205, 196, 0.2), rgba(68, 160, 141, 0.2));
-          border-color: rgba(78, 205, 196, 0.5);
-        }
-
-        .service-link .service-icon {
-          font-size: 1.1rem;
-        }
-
-        .service-link .service-status {
-          width: 6px;
-          height: 6px;
-          border-radius: 50%;
-          background: var(--accent-primary);
-          margin-left: 0.25rem;
-        }
-
-        @media (max-width: 600px) {
-          .services-nav {
-            flex-direction: column;
-            align-items: flex-start;
-          }
                 }
             `}</style>
-    </nav>
+        </>
     );
 }
 

packages/meta-sort-ui/src/meta-service-menu.js

@@ -0,0 +1,303 @@
+/**
+ * <meta-service-menu> — the neighbouring meta-* services, as a burger menu.
+ *
+ * Replaces the eight divergent "services bar" implementations (four copies of
+ * a React `ServiceNav.tsx`, two mirrored `services.js`, two bespoke inline
+ * ones) with a single framework-free custom element. It drops into the React
+ * dashboards as a plain tag — no React dependency — and into the vanilla UIs
+ * as an ES module.
+ *
+ * Data comes from the host service's own `GET /api/neighbors`, same-origin.
+ * Never cross-origin: the dev stack's self-signed certs and the OIDC redirects
+ * make a fetch to a neighbour a dead end. Links are plain navigations.
+ *
+ * ⚠ MIRRORED FILE. Byte-identical copies live in every meta-* UI tree; see
+ * `scripts/check-mirrors.sh`. Edit one → edit all.
+ *
+ * Shadow DOM is not optional here. The eight UIs use four incompatible token
+ * vocabularies, and two of them define *different colours under the same
+ * names* (`--bg-secondary` is #12121a in meta-sort, #16213e in meta-core,
+ * #161b22 in meta-dup). meta-search and meta-share are also the only
+ * light-mode-capable UIs, so a hardcoded dark palette would break them.
+ * The element therefore styles itself from four tokens with dark defaults:
+ *
+ *     --mm-nav-fg, --mm-nav-bg, --mm-nav-border, --mm-nav-accent
+ *
+ * Each host maps its own variables onto those, e.g.
+ *     meta-service-menu { --mm-nav-bg: var(--bg-secondary); }
+ *
+ * Attributes:
+ *   current   name of the host service, so it can be marked and not linked
+ *   endpoint  override the default "/api/neighbors"
+ *   label     button tooltip (default "Services")
+ *
+ * Property:
+ *   rewriteUrl  optional (name, url, neighbour) => url, for hosts that must
+ *               translate internal hostnames into browser-reachable ones
+ *               (meta-gateway does this for its dev/prod split).
+ */
+
+const ICONS = {
+  "meta-core": "⚙️",
+  "meta-sort": "📁",
+  "meta-fuse": "🗂️",
+  "meta-stremio": "🎬",
+  "meta-dup": "🔍",
+  "meta-search": "🔎",
+  "meta-share": "🔗",
+  "meta-gateway": "🌉",
+  "meta-watch": "📺",
+  "meta-listen": "🎧",
+  "meta-read": "📖",
+};
+const DEFAULT_ICON = "📦";
+const POLL_MS = 30000;
+
+function titleCase(name) {
+  return String(name || "")
+    .split("-")
+    .map((w) => w.charAt(0).toUpperCase() + w.slice(1))
+    .join(" ");
+}
+
+const TEMPLATE = `
+<style>
+  :host {
+    --_fg: var(--mm-nav-fg, #e8eaed);
+    --_bg: var(--mm-nav-bg, #1a1a2e);
+    --_border: var(--mm-nav-border, rgba(255, 255, 255, 0.14));
+    --_accent: var(--mm-nav-accent, #4ecdc4);
+    position: relative;
+    display: inline-block;
+    font-family: inherit;
+    font-size: 14px;
+    line-height: 1.4;
+  }
+  button.trigger {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    gap: 0.4rem;
+    width: 2.1rem;
+    height: 2.1rem;
+    padding: 0;
+    cursor: pointer;
+    color: var(--_fg);
+    background: transparent;
+    border: 1px solid var(--_border);
+    border-radius: 8px;
+    font: inherit;
+    transition: border-color 0.15s, background 0.15s;
+  }
+  button.trigger:hover { border-color: var(--_accent); }
+  button.trigger:focus-visible {
+    outline: 2px solid var(--_accent);
+    outline-offset: 2px;
+  }
+  button.trigger[aria-expanded="true"] { border-color: var(--_accent); }
+  .bars { display: block; width: 15px; }
+  .bars span {
+    display: block;
+    height: 2px;
+    margin: 3px 0;
+    border-radius: 2px;
+    background: currentColor;
+  }
+  .panel {
+    position: absolute;
+    top: calc(100% + 6px);
+    right: 0;
+    z-index: 1000;
+    min-width: 13rem;
+    max-height: 70vh;
+    overflow-y: auto;
+    padding: 0.3rem;
+    background: var(--_bg);
+    border: 1px solid var(--_border);
+    border-radius: 10px;
+    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
+  }
+  .panel[hidden] { display: none; }
+  a.item, .item {
+    display: flex;
+    align-items: center;
+    gap: 0.55rem;
+    padding: 0.45rem 0.6rem;
+    border-radius: 6px;
+    color: var(--_fg);
+    text-decoration: none;
+    white-space: nowrap;
+  }
+  a.item:hover { background: color-mix(in srgb, var(--_accent) 18%, transparent); }
+  .item.active { color: var(--_accent); font-weight: 600; cursor: default; }
+  .item.dead { opacity: 0.55; cursor: not-allowed; }
+  .icon { font-size: 1rem; line-height: 1; }
+  .dot {
+    width: 6px;
+    height: 6px;
+    margin-left: auto;
+    border-radius: 50%;
+    background: var(--_accent);
+  }
+  .empty {
+    padding: 0.6rem;
+    opacity: 0.7;
+    font-size: 0.85em;
+    white-space: nowrap;
+  }
+  /* Respect a host that opts out of motion. */
+  @media (prefers-reduced-motion: reduce) {
+    button.trigger { transition: none; }
+  }
+</style>
+<button class="trigger" type="button" aria-haspopup="menu" aria-expanded="false">
+  <span class="bars" aria-hidden="true"><span></span><span></span><span></span></span>
+</button>
+<div class="panel" role="menu" hidden></div>
+`;
+
+class MetaServiceMenu extends HTMLElement {
+  constructor() {
+    super();
+    this.attachShadow({ mode: "open" });
+    this.shadowRoot.innerHTML = TEMPLATE;
+    this._btn = this.shadowRoot.querySelector("button.trigger");
+    this._panel = this.shadowRoot.querySelector(".panel");
+    this._neighbors = [];
+    this._timer = null;
+    this._open = false;
+
+    this._onDocClick = (e) => {
+      if (!this._open) return;
+      if (e.composedPath().includes(this)) return;
+      this._setOpen(false);
+    };
+    this._onKey = (e) => {
+      if (e.key === "Escape" && this._open) {
+        this._setOpen(false);
+        this._btn.focus();
+      }
+    };
+  }
+
+  connectedCallback() {
+    this._btn.title = this.getAttribute("label") || "Services";
+    this._btn.setAttribute("aria-label", this._btn.title);
+    this._btn.addEventListener("click", () => this._setOpen(!this._open));
+    document.addEventListener("click", this._onDocClick);
+    document.addEventListener("keydown", this._onKey);
+
+    this.refresh();
+    this._timer = setInterval(() => this.refresh(), POLL_MS);
+  }
+
+  disconnectedCallback() {
+    if (this._timer) clearInterval(this._timer);
+    this._timer = null;
+    document.removeEventListener("click", this._onDocClick);
+    document.removeEventListener("keydown", this._onKey);
+  }
+
+  get endpoint() {
+    return this.getAttribute("endpoint") || "/api/neighbors";
+  }
+
+  get current() {
+    return this.getAttribute("current") || "";
+  }
+
+  async refresh() {
+    try {
+      const res = await fetch(this.endpoint, {
+        headers: { Accept: "application/json" },
+      });
+      if (!res.ok) throw new Error(String(res.status));
+      const data = await res.json();
+      // `services` is the legacy alias some backends still emit.
+      this._neighbors = data.neighbors || data.services || [];
+    } catch {
+      // Silent: the menu is navigation, not a health indicator. Keep whatever
+      // we last had rather than blanking the list on one failed poll.
+    }
+    this._render();
+  }
+
+  _setOpen(open) {
+    this._open = open;
+    this._panel.hidden = !open;
+    this._btn.setAttribute("aria-expanded", String(open));
+    if (open) this.refresh();
+  }
+
+  _render() {
+    const panel = this._panel;
+    panel.textContent = "";
+
+    const seen = new Set();
+    const rows = [];
+    for (const n of this._neighbors) {
+      const name = n.name || "";
+      if (!name || seen.has(name)) continue;
+      seen.add(name);
+      rows.push(n);
+    }
+    // Always show the host itself, even before its own echo comes back.
+    if (this.current && !seen.has(this.current)) {
+      rows.push({ name: this.current, baseUrl: "" });
+    }
+    rows.sort((a, b) => String(a.name).localeCompare(String(b.name)));
+
+    if (rows.length === 0) {
+      const empty = document.createElement("div");
+      empty.className = "empty";
+      empty.textContent = "No services found";
+      panel.appendChild(empty);
+      return;
+    }
+
+    for (const n of rows) {
+      const isActive = n.name === this.current;
+      let url = n.baseUrl || "";
+      if (typeof this.rewriteUrl === "function") {
+        try {
+          url = this.rewriteUrl(n.name, url, n) || "";
+        } catch {
+          /* a bad hook must not blank the menu */
+        }
+      }
+
+      // A neighbour with no reachable URL is shown but not linked — better
+      // than a link that goes nowhere.
+      const el = document.createElement(isActive || !url ? "span" : "a");
+      el.className =
+        "item" + (isActive ? " active" : "") + (!isActive && !url ? " dead" : "");
+      if (el.tagName === "A") {
+        el.href = url;
+        el.setAttribute("role", "menuitem");
+      }
+      if (!isActive && !url) el.title = "No reachable URL announced";
+
+      const icon = document.createElement("span");
+      icon.className = "icon";
+      icon.textContent = ICONS[n.name] || DEFAULT_ICON;
+
+      const label = document.createElement("span");
+      label.textContent = titleCase(n.name);
+
+      el.append(icon, label);
+      if (n.status === "running" || isActive) {
+        const dot = document.createElement("span");
+        dot.className = "dot";
+        dot.title = n.status || "running";
+        el.appendChild(dot);
+      }
+      panel.appendChild(el);
+    }
+  }
+}
+
+if (!customElements.get("meta-service-menu")) {
+  customElements.define("meta-service-menu", MetaServiceMenu);
+}
+
+export default MetaServiceMenu;

packages/meta-sort-ui/src/pages/Monitor.tsx

@@ -1,4 +1,4 @@
-import { useState, useEffect, useCallback } from 'react';
+import { useState, useEffect, useCallback, useRef } from 'react';
 import {
     ProcessingStatus,
     Metrics,
@@ -60,29 +60,35 @@ function Monitor() {
     const [failedFiles, setFailedFiles] = useState<FailedFile[]>([]);
     const [showPipelineHelp, setShowPipelineHelp] = useState(false);
 
-    const fetchData = useCallback(async () => {
+    // Each endpoint renders as soon as it answers, so one slow or failing call
-        try {
+    // cannot blank the page. A tick is skipped while the previous one is still
-            const [statusRes, metricsRes, queueRes, statsRes, failedRes] = await Promise.all([
+    // out, so a slow backend never collects a pile of overlapping polls.
-                fetch('/api/processing/status'),
+    const pollInFlight = useRef(false);
-                fetch('/api/metrics'),
-                fetch('/api/processing/queue'),
-                fetch('/api/stats'),
-                fetch('/api/processing/failed')
-            ]);
 
-            if (statusRes.ok) setStatus(await statusRes.json());
+    const fetchData = useCallback(async () => {
-            if (metricsRes.ok) setMetrics(await metricsRes.json());
+        if (pollInFlight.current) return;
-            if (queueRes.ok) {
+        pollInFlight.current = true;
-                const queueData = await queueRes.json();
+
-                setQueue(queueData.items || []);
+        const load = async <T,>(url: string, apply: (data: T) => void) => {
+            const res = await fetch(url);
+            if (res.ok) apply(await res.json());
+        };
+
+        try {
+            const results = await Promise.allSettled([
+                load<ProcessingStatus>('/api/processing/status', setStatus),
+                load<Metrics>('/api/metrics', setMetrics),
+                load<{ items?: QueueItem[] }>('/api/processing/queue', (data) => setQueue(data.items || [])),
+                load<RedisStats>('/api/stats', setRedisStats),
+                load<{ failedFiles?: FailedFile[] }>('/api/processing/failed', (data) => setFailedFiles(data.failedFiles || [])),
+            ]);
+            for (const result of results) {
+                if (result.status === 'rejected') {
+                    console.error('Failed to fetch data:', result.reason);
                 }
-            if (statsRes.ok) setRedisStats(await statsRes.json());
-            if (failedRes.ok) {
-                const failedData = await failedRes.json();
-                setFailedFiles(failedData.failedFiles || []);
             }
-        } catch (err) {
+        } finally {
-            console.error('Failed to fetch data:', err);
+            pollInFlight.current = false;
         }
     }, []);
 
@@ -410,7 +416,7 @@ function Monitor() {
                     <h3 className="section-title">File Coverage</h3>
                     <div className="stats-grid">
                         <div className="stat-box">
-                            <div className="stat-value">{status?.uniqueHashes ? formatNumber(status.uniqueHashes) : (redisStats ? formatNumber(redisStats.fileCount) : '-')}</div>
+                            <div className="stat-value">{status?.uniqueHashes ? formatNumber(status.uniqueHashes) : (redisStats?.fileCount != null ? formatNumber(redisStats.fileCount) : '-')}</div>
                             <div className="stat-label">Unique Files</div>
                         </div>
                         <div className="stat-box">
@@ -432,7 +438,7 @@ function Monitor() {
                 <div className="card total-size-card">
                     <h2>Total Size</h2>
                     <div className="total-size-value">
-                        {redisStats ? formatBytes(redisStats.totalSize) : '-'}
+                        {redisStats?.totalSize != null ? formatBytes(redisStats.totalSize) : '-'}
                     </div>
                     <div className="total-size-label">Watch Folders</div>
                 </div>

packages/meta-sort-ui/src/types/index.ts

@@ -184,12 +184,12 @@ export interface Metrics {
 
 // NOTE: DuplicateGroup and DuplicateData types have been moved to meta-dup service
 
+/** GET /api/stats: totals over meta-core's file-backed roots. */
 export interface RedisStats {
-    fileCount: number;
+    /** null when meta-core cannot supply file totals (source 'unavailable') */
-    keyCount: number;
+    fileCount: number | null;
-    totalSize: number;
+    totalSize: number | null;
-    memoryUsage?: string;
+    source?: 'meta-core' | 'unavailable';
-    memoryUsageBytes?: number;
 }
 
 export interface QueueItem {

packages/shared/meta-interface/src/lib/MetaData.test.ts

@@ -22,13 +22,13 @@ describe('MetaData', () => {
     });
 
     it('should set and get nested metadata using nested keys', () => {
-        root.at('titles').at('eng').set("Star Wars");
+        root.at('titles').at('eng').at('Star Wars').set(true);
-        root.at('titles').at('jpn').set("Staru Warsu");
+        root.at('titles').at('jpn').at('Staru Warsu').set(true);
-        expect(root.at('titles').at('eng').get()).to.equal("Star Wars");
+        expect(root.at('titles').at('eng').at('Star Wars').get()).to.equal(true);
-        expect(root.at('titles').at('jpn').get()).to.equal("Staru Warsu");
+        expect(root.at('titles').at('jpn').at('Staru Warsu').get()).to.equal(true);
-        expect(root.at('titles').get()).to.deep.equal({eng: "Star Wars", jpn: "Staru Warsu"});
+        expect(root.at('titles').get()).to.deep.equal({eng: {"Star Wars": true}, jpn: {"Staru Warsu": true}});
         expect(root.get()).to.deep.equal({
-            titles: {eng: "Star Wars", jpn: "Staru Warsu"}
+            titles: {eng: {"Star Wars": true}, jpn: {"Staru Warsu": true}}
         });
     });
 

packages/shared/meta-interface/src/lib/metadata-type/VideoMeta.ts

@@ -8,8 +8,9 @@ export interface VideoMeta {
     increment?: string;
     movieYear?: string;
     videoType?: VideoType;
+    title?: string;//display title (localized); the one name to show
     originalTitle?: string;//title in original language
-    titles?: LanguageData<string>;// <ISO 639-3 lang codes, title>
+    titles?: LanguageData<Record<string, true>>;// key-set: <ISO 639-3 lang code, {name: true}> — every clean name incl. AKAs (METADATA_KEYS.md §3)
 }
 
 export const VideoMetaFields = [