Full-stack TypeScript engineer. Node/Hono + Next.js + Postgres, live SaaS, ongoing

Solo-built SaaS product, already deployed and in use. I need a second engineer so work stops shipping one thing at a time. Stack: TypeScript 6 strict, Node 22, pnpm monorepo. Hono API on Railway, Next.js 15 on Vercel. Postgres 17 on Supabase with Drizzle and row-level security. Inngest for background jobs. The work: third-party API integrations (OAuth, sync, normalizing vendor data into our schema), ingestion pipelines, and general product features. Ongoing, driven by what users hit. What matters here: - Large test suite and a gate that stays green. Nothing merges red. How the tests get written is your business. - Anything touching an external API gets checked against the real thing before it ships, not assumed. - Multi-tenant isolation is enforced at the database level. - The conventions are already set across the repo. New code matches them. Answer these three instead of sending a template. I read every one. 1. What have you shipped? Link the code or the product if you can, otherwise describe the system and which part was yours. 2. The toughest problem you've hit in development, and how you solved it. 3. Which AI tools do you code with, and where have you learned not to trust them?