Senior Product Engineer, React Native + Backend

About Base
Base is a platform for in-real-life social connection and community. Our Members are accomplished people who have built careers, families, and reputations. They come to Base for what their calendars are missing: regular, in-person time with peers they actually want to know. The gathering is the product.

The systems that make it possible are what this role exists to protect.

Engagement

Contract:

4 to 6 week paid audit, with the option to extend into implementation.

About the Role
We’re looking for a senior, hands‑on engineer to audit and stabilize a consumer mobile product and its internal admin tool, Home Base. This is a 4‑week paid trial: come in, understand the system fast, separate the real problems from the noise, and ship. It’s a stabilization engagement, not a net‑new feature role. The long‑term build-and-own seat is a separate Tech Lead position.

The system spans a React Native + Expo mobile app, a Type Script monorepo, two backend APIs on AWS (a member‑facing API and an admin/back‑office API) that run the Stripe payment, subscription, and refund integrations, a Supabase Postgres database with hundreds of migrations, an automation and data‑integration layer (n8n‑style workflows plus reverse‑ETL into downstream tools), and Metabase reporting. Parts of it are mid‑migration and lightly tested.

This is not a greenfield build. We need someone who can quickly understand an existing codebase, identify architectural and execution risks, separate real problems from noise, and ship fixes that hold.

What You’ll Do

• Audit the React Native + Expo mobile app and the Home Base admin flows.

• Review the backend and API structure, the Postgres data models, and the business logic around bookings, guests, cancellations, refunds, credits, and notifications.

• Trace the payment path (Stripe) and the automation / data‑integration layer (n8n‑style workflows and reverse‑ETL) for fragility and silent‑failure points.

• Identify technical debt, broken workflows, security gaps, stale code, and missing tests.

• Review Linear and project artifacts, and compare planned work against what actually shipped.

• Produce a prioritized technical recovery plan.

• Ship or supervise one small but meaningful stabilization fix during the trial.

• Recommend the exact team needed to continue: mobile, backend, data, QA, or design.

Must Have

• Senior or staff‑level full‑stack experience shipping production React Native + Type Script apps.

• Strong backend experience building and operating GraphQL APIs on a relational database (Postgres or similar), deployed on a cloud provider. We run AWS + Supabase.

• Hands‑on Stripe across subscriptions, refunds, invoices, webhooks, and reconciliation, integrated into backend services (ours run on AWS).

• You’ve worked inside messy, partially‑migrated, lightly‑tested systems and brought order without freezing delivery.

• You make fast, pragmatic judgment calls in unfamiliar code and explain them clearly to a non‑technical founder.

• Comfort working without perfect specs.

Nice to Have

• Experience with Metabase or analytics cleanup

• Experience migrating away from Native Base, Native Wind, or inconsistent styling systems

• Experience with mobile release pipelines, QA automation, push notifications, and email workflows

• Prior startup rescue, code audit, or fractional CTO experience

• Expo and EAS builds in production, with manual store submission (no OTA).

• Apollo Client and GraphQL on the front end.

• Supabase specifically (Auth, Postgres, Storage).

• Automation glue and reverse‑ETL: n8n, Hightouch, Airflow, or similar.

• Stripe in a booking, marketplace, or membership context.

• Mobile observability and E2E testing:
  Sentry, Post Hog, Maestro.

• Metabase or analytics cleanup.

• Migrating away from Native Base, Native Wind, or inconsistent styling systems.

• Untanglin…