# Deepgram Reference Architecture

> Implement Deepgram reference architecture for scalable transcription systems.

Implement Deepgram reference architecture for scalable transcription systems.
Use when designing transcription pipelines, building production architectures,
or planning Deepgram integration at scale.
Trigger: "deepgram architecture", "transcription pipeline", "deepgram system design",
"deepgram at scale", "enterprise deepgram", "deepgram queue".

- Page: https://ss33.ai/skills/jeremylongshore/deepgram-reference-architecture-3994186055
- Publisher: jeremylongshore
- Category: [Software Development](https://ss33.ai/skills/category/software-development-t44z8z) › [APIs & backend](https://ss33.ai/skills/category/software-development-t44z8z/apis-and-backend-t0x840)
- License: MIT
- Source: https://github.com/jeremylongshore/tons-of-skills-marketplace/blob/6cc8e76343714d8807b4a5f1aa604b7ede5e497f/plugins/saas-packs/deepgram-pack/skills/deepgram-reference-architecture/SKILL.md

## Skill

SKILL.md: https://ss33.ai/api/v1/ss33/download/jeremylongshore/deepgram-reference-architecture-3994186055

# Deepgram Reference Architecture

## Prerequisites

- A documented audio/transcript data flow, consent/retention policy, approved environment boundaries, and service/data owners.
- Reviewed interfaces for auth, media ingestion, callbacks, observability, storage, and incident response.

## Examples

Model a development producer that validates media metadata, sends a request using a scoped project key, receives a signed callback, and records only correlation/state metrics. Promote the same versioned contract through staging before a production canary, retaining a dead-letter/recovery owner and excluding audio/transcript content from telemetry.

## Overview

Four reference architectures for Deepgram transcription at scale: synchronous REST for short files, async queue (BullMQ) for batch processing, WebSocket proxy for real-time streaming, and a hybrid router that auto-selects the best pattern based on audio duration.

## Architecture Selection Guide

| Pattern | Best For | Latency | Throughput | Complexity |
|---------|----------|---------|------------|------------|
| Sync REST | Files <60s, low volume | Low | Low | Simple |
| Async Queue | Batch, files >60s | Medium | High | Medium |
| WebSocket Proxy | Live audio, real-time | Real-time | Medium | Medium |
| Hybrid Router | Mixed workloads | Varies | High | High |
| Callback | Files >5min, fire-and-forget | N/A | Very High | Low |

## Instructions

### Step 1: Synchronous REST Pattern

```typescript
import express from 'express';
import { createClient } from '@deepgram/sdk';

const app = express();
app.use(express.json());

const deepgram = createClient(process.env.DEEPGRAM_API_KEY!);

// Direct API call — best for short files (<60s)
app.post('/api/transcribe', async (req, res) => {
  const { url, model = 'nova-3', diarize = false } = req.body;

  try {
    const { result, error } = await deepgram.listen.prerecorded.transcribeUrl(
      { url },
      { model, smart_format: true, diarize, utterances: diarize }
    );
    if (error) return res.status(502).json({ error: error.message });

    res.json({
      transcript: result.results.channels[0].alternatives[0].transcript,
      confidence: result.results.channels[0].alternatives[0].confidence,
      duration: result.metadata.duration,
      request_id: result.metadata.request_id,
      utterances: diarize ? result.results.utterances : undefined,
    });
  } catch (err: any) {
    res.status(500).json({ error: err.message });
  }
});
```

### Step 2: Async Queue Pattern (BullMQ)

```typescript
import { Queue, Worker, Job } from 'bullmq';
import { createClient } from '@deepgram/sdk';
import Redis from 'ioredis';

const connection = new Redis(process.env.REDIS_URL ?? 'redis://localhost:6379');

// Producer: submit transcription jobs
const transcriptionQueue = new Queue('transcription', { connection });

async function submitJob(audioUrl: string, options: Record<string, any> = {}) {
  const job = await transcriptionQueue.add('transcribe', {
    audioUrl,
    model: options.model ?? 'nova-3',
    diarize: options.diarize ?? false,
    submittedAt: new Date().toISOString(),
  }, {
    attempts: 3,
    backoff: { type: 'exponential', delay: 5000 },
    removeOnComplete: { age: 86400 },  // Keep for 24h
  });

  console.log(`Job submitted: ${job.id}`);
  return job.id;
}

// Consumer: process transcription jobs
const deepgram = createClient(process.env.DEEPGRAM_API_KEY!);

const worker = new Worker('transcription', async (job: Job) => {
  const { audioUrl, model, diarize } = job.data;
  console.log(`Processing job ${job.id}: ${audioUrl}`);

  const { result, error } = await deepgram.listen.prerecorded.transcribeUrl(
    { url: audioUrl },
    { model, smart_format: true, diarize, utterances: diarize }
  );

  if (error) throw new Error(`Deepgram error: ${error.message}`);

  const output = {
    transcript: result.results.channels[0].alternatives[0].transcript,
    confidence: result.results.channels[0].alternatives[0].confidence,
    duration: result.metadata.duration,
    request_id: result.metadata.request_id,
  };

  // Store result (database, S3, etc.)
  console.log(`Job ${job.id} complete: ${output.duration}s audio`);
  return output;
}, {
  connection,
  concurrency: 10,     // Process 10 jobs simultaneously
  limiter: {
    max: 50,           // Max 50 per time window
    duration: 60000,   // Per minute
  },
});

worker.on('completed', (job) => console.log(`Completed: ${job.id}`));
worker.on('failed', (job, err) => console.error(`Failed: ${job?.id}`, err.message));
```

### Step 3: WebSocket Proxy for Real-Time

```typescript
import { WebSocketServer, WebSocket } from 'ws';
import { createClient, LiveTranscriptionEvents } from '@deepgram/sdk';

const wss = new WebSocketServer({ port: 8080 });

wss.on('connection', (clientWs: WebSocket) => {
  console.log('Client connected');

  const deepgram = createClient(process.env.DEEPGRAM_API_KEY!);
  const dgConnection = deepgram.listen.live({
    model: 'nova-3',
    smart_format: true,
    interim_results: true,
    utterance_end_ms: 1000,
    encoding: 'linear16',
    sample_rate: 16000,
    channels: 1,
  });

  // Forward Deepgram transcripts to client
  dgConnection.on(LiveTranscriptionEvents.Transcript, (data) => {
    const transcript = data.channel.alternatives[0]?.transcript;
    if (transcript && clientWs.readyState === WebSocket.OPEN) {
      clientWs.send(JSON.stringify({
        type: 'transcript',
        text: transcript,
        is_final: data.is_final,
        speech_final: data.speech_final,
      }));
    }
  });

  dgConnection.on(LiveTranscriptionEvents.UtteranceEnd, () => {
    if (clientWs.readyState === WebSocket.OPEN) {
      clientWs.send(JSON.stringify({ type: 'utterance_end' }));
    }
  });

  // Forward client audio to Deepgram
  clientWs.on('message', (data: Buffer) => {
    if (dgConnection.getReadyState() === 1) {
      dgConnection.send(data);
    }
  });

  // Cleanup on disconnect
  clientWs.on('close', () => {
    dgConnection.finish();
    console.log('Client disconnected');
  });

  dgConnection.on(LiveTranscriptionEvents.Error, (err) => {
    console.error('Deepgram error:', err.message);
    clientWs.close();
  });
});

console.log('WebSocket proxy on ws://localhost:8080');
```

### Step 4: Hybrid Router

```typescript
import { createClient } from '@deepgram/sdk';

class TranscriptionRouter {
  private client: ReturnType<typeof createClient>;
  private queue: typeof transcriptionQueue;

  constructor(apiKey: string, queue: any) {
    this.client = createClient(apiKey);
    this.queue = queue;
  }

  async route(audioUrl: string, options: {
    mode?: 'sync' | 'async' | 'callback' | 'auto';
    estimatedDuration?: number;  // seconds
    callbackUrl?: string;
    model?: string;
    diarize?: boolean;
  } = {}) {
    const mode = options.mode ?? 'auto';
    const duration = options.estimatedDuration ?? 0;

    // Auto-select based on duration
    const selectedMode = mode === 'auto'
      ? duration > 300 ? 'callback'   // >5 min: use callback
        : duration > 60 ? 'async'     // >60s: use queue
        : 'sync'                       // <60s: direct API
      : mode;

    console.log(`Routing: ${selectedMode} (est. ${duration}s)`);

    switch (selectedMode) {
      case 'sync':
        return this.syncTranscribe(audioUrl, options);
      case 'async':
        return this.asyncTranscribe(audioUrl, options);
      case 'callback':
        return this.callbackTranscribe(audioUrl, options);
    }
  }

  private async syncTranscribe(url: string, opts: any) {
    const { result, error } = await this.client.listen.prerecorded.transcribeUrl(
      { url },
      { model: opts.model ?? 'nova-3', smart_format: true, diarize: opts.diarize }
    );
    if (error) throw error;
    return { mode: 'sync', result };
  }

  private async asyncTranscribe(url: string, opts: any) {
    const jobId = await submitJob(url, opts);
    return { mode: 'async', jobId };
  }

  private async callbackTranscribe(url: string, opts: any) {
    const { result } = await this.client.listen.prerecorded.transcribeUrl(
      { url },
      { model: opts.model ?? 'nova-3', smart_format: true, callback: opts.callbackUrl }
    );
    return { mode: 'callback', requestId: result.metadata.request_id };
  }
}
```

### Step 5: Architecture Diagram

```
                    ┌──────────────┐
                    │   Client     │
                    └──────┬───────┘
                           │
                    ┌──────▼───────┐
                    │   API Gateway │
                    │  /transcribe  │
                    └──────┬───────┘
                           │
                    ┌──────▼───────┐
                    │ Hybrid Router │
                    └──┬───┬───┬───┘
                       │   │   │
           ┌───────────┘   │   └───────────┐
           ▼               ▼               ▼
    ┌──────────┐   ┌──────────┐   ┌──────────┐
    │   Sync   │   │  Queue   │   │ Callback │
    │  (<60s)  │   │ (BullMQ) │   │  (>5min) │
    └────┬─────┘   └────┬─────┘   └────┬─────┘
         │              │              │
         └──────────┬───┘──────────────┘
                    │
            ┌───────▼──────┐
            │  Deepgram    │
            │  API         │
            └───────┬──────┘
                    │
            ┌───────▼──────┐
            │   Results    │
            │   Store      │
            └──────────────┘
```

## Output

- Sync REST endpoint for short files
- BullMQ queue with workers for batch processing
- WebSocket proxy for real-time streaming
- Hybrid router with auto-mode selection
- Architecture diagram

## Error Handling

| Issue | Cause | Solution |
|-------|-------|----------|
| Sync timeout on large file | Wrong pattern selected | Use async queue or callback |
| Queue backlog growing | Workers overloaded | Scale workers, increase concurrency |
| WebSocket disconnects | Network instability | Auto-reconnect with backoff |
| Callback not received | Endpoint unreachable | Check HTTPS, verify callback URL |

## Resources

- Deepgram Architecture Guide
- [BullMQ Documentation](https://docs.bullmq.io/)
- [WebSocket API](https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API)