welldun
Building at the seam of software and AI — and writing up how it works.
welldun is where I build and document practical software + AI infrastructure. The pattern across everything here is the same: multi-tenant by default, bring-your-own-keys, with security and reliability treated as features rather than afterthoughts — and AI used where it genuinely earns its place, not as decoration.
What's being built
- Entity platform (Drafting Table) — a platform where each customer defines their own entities, fields, and relationships, and the system generates the storage, validation, APIs, and analytics from those definitions. No per-customer code. Read the series →
- Voice infra — a Retell-style, multi-tenant voice-calling backend: STT + LLM + TTS orchestrated end to end, bring-your-own provider keys (stored with envelope encryption), consumable by any third party over a plain API.
- Email infra — a multi-tenant email-sending API: connect your own SendGrid/Resend keys, send through one reliable surface, with a Postgres work queue, circuit breaking, idempotent writes, and signed delivery webhooks.
- Workflow automation — a visual builder (React Flow) over a durable execution engine, where adding a custom block is a single file.
The writing here is the running field notebook for these — the architecture bets, the gotchas, and the things that only show up once you ship and measure.
Me
I'm Anirudh. Previously at Stripe; now founder of Valyx, a B2B startup. I like building systems and taking them apart in writing — the kind of write-up I wish existed when I was figuring the thing out.
Reach me at anirudh@valyx.com, or follow along via the RSS feed.