Senior Full-Stack Engineer for AI Platform

About us WebPanda is an AI-native marketing agency for home service contractors. We have 40+ paying clients and we're replacing human marketing fulfillment with AI agents, delivering the same outcomes at software margins. We're building the platform that does the work, and we're moving fast toward a hard deadline. You'd be the senior technical lead working directly with the founder and two junior engineers. We need to develop a strong MVP in 30 days. The role You own the architecture and the highest-stakes parts of the build. Our platform collects data on each client, diagnoses what's holding back their local search visibility, executes fixes (optimizing Google Business Profiles, publishing pages to client websites, fixing schema, managing citations), and measures the results, all operated across our full client book from one console. You'll design the execution pipeline, own everything that writes to live client assets, review the juniors' work, and set the technical bar. This is a fast, intense sprint with a clear deliverable. Strong performance turns into a long-term lead role. Must-have experience You've built and shipped production SaaS, not just prototypes. Specifically: Next.js 15 (App Router) and modern React, in production. Supabase or Postgres at a real level: schema design, row-level security, and multi-tenant data isolation. You understand why tenant isolation is a security problem, not just a query filter. Drizzle ORM or comparable typed query layers. Background job systems (Inngest, Temporal, BullMQ, or similar): event-driven workflows, retries, idempotency, scheduled jobs. Third-party API integrations with OAuth, especially write operations against external systems where a bad call damages something real. You've handled token refresh, rate limits, and field-level update masks. Google API experience (Business Profile, OAuth) is a strong plus. TypeScript fluency throughout. What separates the candidate we want You think in blast radius. You instinctively separate code where a bug shows up on screen and gets caught from code where a bug silently corrupts client data, and you treat those differently. You design deploy safety: whitelisted operations, before-state snapshots, rollback paths, rate limiting on writes to live systems. You've integrated LLM APIs (Anthropic, OpenAI) into real product workflows with structured output validation, not just chat features. You can review and mentor junior engineers who lean on AI coding tools, and you raise their output rather than redoing it. You ship fast without shipping fragile. Nice to have WordPress REST API and custom plugin development. Firecrawl, DataForSEO, or other crawling and SERP data tools. Local SEO or martech domain familiarity. Prior founding-engineer or early-startup experience where you owned architecture end to end. Logistics Full-time contract, starting immediately (this week if possible). Remote, with strong overlap with US hours required for fast iteration. How we hire (fast) A 45-minute call where you walk us through a system you designed and scaled. Then a paid 2-hour trial: we give you read access to our actual codebase, you critique the architecture and verbally design a specific piece of our execution pipeline with us. We're hiring within days, not weeks. To apply Send a short note on the most complex production system you've owned, with emphasis on how you handled writes to external systems and how you kept multi-tenant data isolated. Include your GitHub or portfolio and your availability to start.