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How I split the embedding workflow in Qdrant into clear steps

I rebuilt the worker so that one capture produces multiple token chunks, each chunk is embedded individually, and storage in Qdrant remains completely isolated.

I rebuilt the worker so that one capture produces multiple token chunks, each chunk is embedded individually, and storage in Qdrant remains completely isolated.

Contents

The new worker flow

Once the diagnosis and strategic decision were clear, I moved on to refactoring the ingestion pipeline. Instead of handling everything in one error-prone step, I split the IngestWorker, powered by BullMQ, into a clean, multi-stage pipeline.

The flow can be summarized as follows:

1. Input text
2. Fetch Capture Record (PostgreSQL as source of truth)
3. Build Structured Document (platform-specific strategies)
4. Token-based chunking (XLM-RoBERTa, 1500 tokens, 150 overlap)
5. Generate Embeddings (high-speed in-memory cache in ai-provider)
6. Atomically store points in Qdrant (shared collection, userId keyword index)
7. Update Database Status (marked as "done")

This finer-grained structure turns one large, unpredictable request into a sequence of manageable and fully controllable processing steps.

Why I store each chunk individually

Creating a single vector for a long post is imprecise. We would flatten valuable detail. If we instead embed each chunk individually and store it as a separate data point, a search query can identify the most relevant text section precisely.

To do that, we store the chunks in Qdrant with a shared reference:

// Storing chunked points with shared metadata for retrieval
const points = vectors.map((vector, index) => {
  return {
    id: randomUUID(),
    vector,
    payload: {
      ...payload,
      chunkIndex: index,
      chunkCount,
    },
  };
});

To keep CPU and API load low, we implemented a high-speed in-memory cache in the AI provider. If the same text section needs embedding again, for example during retries, the cache responds immediately and prevents unnecessary model inference.

Single shared collection and tenant isolation

A major part of the refactoring concerns the vector database design. Previously, we created a separate Qdrant collection for each user. Operationally, that scaled very poorly and caused substantial RAM and connection overhead.

We now use a single shared collection named local_insight_memory for all users. Data separation, or multi-tenancy, is enforced consistently at the application level:

  • Every stored chunk object must have a userId attribute.
  • To ensure fast filtering in the O(1) range, we automatically create a keyword payload index on the userId field in Qdrant at server startup.
  • All read and search operations enforce a filter on this userId on the server side.
  • To optimize Qdrant’s memory requirements, chunk payloads are reduced to the minimum necessary metadata: tags, notes, platform, source channel, timestamp, captureId and userId.

Atomic rollbacks for maximum consistency

What happens if ingestion stops halfway through? If the S3 upload succeeds but enqueueing fails, orphaned data can remain.

To address this, we implemented a robust error rollback system in the /ingest orchestrator. If a later step fails, PostgreSQL rows already created and images uploaded to MinIO/S3 are deleted immediately with deleteCapture and deleteImage. Ingestion is considered successful only when all phases complete without errors.


All articles in the series

  1. Vision and system overview: Chrome Extension, RAG architecture and project background: Read article
  2. Building a RAG system: Qdrant, embeddings and cosine similarity in TypeScript: Read article
  3. AI provider abstraction: Ollama vs. OpenAI, interface design and no vendor lock-in: Read article
  4. Chrome Extension MV3: Three isolated runtime contexts, message passing and Strategy Pattern: Read article
  5. Docker Compose strategy: The override pattern, from local development to Azure: Read article
  6. Ollama locally vs. Docker: The decision and its consequences: Read article
  7. Ollama auto-pull entrypoint: Automated model setup at container startup: Read article
  8. tsconfig and Vite: Node16 vs. bundler, and why Vite has its own rules: Read article
  9. Load complete Instagram captions with MutationObserver: Read article
  10. Chrome Extension foundation with health indicator and retry queue: Read article
  11. Phase 2 features: Shadow DOM overlay, Tailwind v4 and duplicate detection: Read article
  12. Race condition in platform detection: How a UI event breaks Instagram detection: Read article
  13. Extracting PostId in two Instagram layouts: querySelector vs. ancestor traversal: Read article
  14. Capture a complete Instagram carousel with MutationObserver: Lazy loading, observer-before-click and timeout fallback: Read article
  15. Notes and tags when saving screenshots: Read article
  16. Instagram keyboard shortcuts block Chrome Extension input: Read article
  17. Lowercase normalization and duplicate detection in tag input: Read article
  18. Zitadel Login V2 in Docker Compose with three hidden errors: Read article
  19. PKCE OAuth in a Chrome MV3 extension: Read article
  20. React frontend with react-oidc-context and Zitadel: Read article
  21. Vite build-time environment variables in Docker: Read article
  22. Event-driven ingestion with BullMQ and Redis: Read article
  23. MinIO instead of Azurite: S3-compatible object storage locally and on Hetzner: Read article
  24. access_token, id_token and the Userinfo endpoint: Which belongs where: Read article
  25. Qdrant multi-tenancy with one collection per user: Read article
  26. When backend and frontend know different types: Read article
  27. Removing Zitadel bootstrap: Host header bug and manual setup: Read article
  28. Backend code review with six problems fixed before launch: Read article
  29. Traefik instead of NGINX: Reverse proxy for a growing Docker Compose stack: Read article
  30. Two-layer rate limiting: Traefik and express-rate-limit with Redis: Read article
  31. Implementing GDPR Article 17 correctly: Promise.allSettled and export batching: Read article
  32. Embedding model lock-in: Why mxbai-embed-large is a permanent production decision: Read article
  33. Docker volumes in production: Named volumes, bind mounts and the Hetzner volume approach: Read article
  34. Two vulnerabilities before launch: Redis without authentication and an exposed Qdrant admin port: Read article
  35. Traefik as the single entry point in the Docker Compose stack: Read article
  36. Connecting Zitadel behind Traefik with issuer, JWKS and Login V2: Read article
  37. Fixing the frontend when the nginx healthcheck fails on localhost: Read article
  38. Observability for my Docker Compose stack with Bull Board and Dozzle: Read article
  39. Open the Qdrant dashboard securely with local Traefik and an SSH tunnel: Read article
  40. Diagnosis of chunking failures despite tokenization: Read article
  41. Why I set the chunk size to 1500 tokens: Read article
  42. Splitting the embedding workflow into clear steps: (this article)
  43. Bringing chunking, storage and search back together: Read article
  44. Capture Intake as a separate module, less orchestration in the Express endpoint: Read article

Working on a similar RAG system and want to evaluate the same structure for your project? Let us assess it together.

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