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Overview · B2B SaaS · Productivity · Realtime collaboration

ScribeStack

Realtime collaborative document workspace for Indian SMBs — CRDT-backed, offline-first, India-resident data.

ScribeStack is a Notion-class collaborative editor optimized for the Indian SMB market.

The architecture is event-sourced over a CRDT (Yjs) for last-writer-wins-free merges, served from a Cloud Run + Firestore core with a websocket fleet on GKE Autopilot for low-latency sync. Documents shard by workspace, search runs on Vertex AI embeddings + BigQuery vector indices, and an analytics pipeline replays the CRDT log into BigQuery for usage insights. The system is designed to land cleanly in asia-south1 (Mumbai) with a hot read replica in asia-south2 (Delhi) for sub-50ms p99 across India, and is GDPR/DPDP ready out of the gate.

At a glance

13
components
6
diagrams
8
patterns applied
9
risks scored
4
scale tiers
₹1.3L–₹2.4L / mo
growth tier cost

Runs in: asia-south1 (Mumbai) · asia-south2 (Delhi) — read replica · Terraform with workspace per environment (dev/stage/prod) · Cloud Build → Artifact Registry → Cloud Deploy (canary 5% → 25% → 100%)

Read in this order

I · The problem

Start with the problem statement and constraints.

II · The design

Inspect the shape, the pieces, and how they talk.

III · The operation

Understand cost, risk, defence, and operations.