# Staff Software Engineer, Ledger at Alt

- Company: Alt
- What the company does: Backed by First Round Capital.
- Company website: https://onlyalt.com
- Type: Startups
- Level: Senior
- Location: Remote
- Work setup: Remote
- Pay: $300K to $500K base salary per year (USD)
- Posted: 2026-09-21
- Apply by: 2026-11-05
- Apply: https://jobs.ashbyhq.com/alt/e0eb543c-efa3-4074-9b60-999e34ee5df7
- Page: https://www.1752.vc/careers/jobs/alt-staff-software-engineer-ledger/

## About the role

This is a builder's seat, not a manager's seat. You will write the ledger, the rails, and the reconciliation yourself. You will make the build-versus-buy call and defend it. You will tell the business no when correctness demands it, and you will be right often enough that they keep asking.

## What they're looking for

- You have owned a double-entry ledger in production. Built one, migrated one, or been the person accountable for one. You can explain a modeling decision you would make differently now, and why
- You have moved real money on real rails. ACH origination and returns, RTP or FedNow, wires, or equivalent. You know what an R01 is, why NACHA return windows matter, and why a credit-push rail changes the product flow and not just the API call
- You have handled large transactions, where the failure mode is a five- or six-figure problem and somebody notices immediately
- Database mastery. Expert SQL and relational design, and a transaction that holds under load at auction close and during scheduled auto-pay batches. Python, Postgres, and AWS are our stack
- You're API-native. Webhooks, idempotency, eventual consistency, and reconciliation are your default vocabulary, not terms you looked up
- You've built real things with AI, not just used it. Agents, skills, MCP servers, connectors, internal tooling people depend on

Tags: Product and Data