Custom Database Engine for Startups: Scale to 1M+ Users

Startups usually start on PostgreSQL or a managed NoSQL service. As you approach 1M+ users, one or two data patterns often dominate—and that’s when a custom engine can reduce cost and latency without rewriting the whole product.

• •DB cost is growing faster than revenue – Your RDS or DynamoDB bill is a big line item.
• •One or two patterns dominate – e.g. session lookup, real-time state, or event append. The rest of the app is “normal” CRUD.
• •Latency is inconsistent – p99 spikes despite tuning; users or partners notice.

Don’t replace everything. Add a custom engine only for the dominant hot path (e.g. session store or event ingest). Keep your existing DB for user accounts, billing, and reporting. Migrate traffic gradually.

For a single hot-path layer: 10–16 weeks, $40K–$80K USA/Canada or ₹15–35 lakh India. Enough to get to 1M+ users on the hot path with predictable cost and latency. At Hendoi we build custom database engines (VeloxDB) for USA, Canada, and Bengaluru. Contact us for a free quote.