Backend
- Strong Python (3.11+) with FastAPI or Django
- Async programming, background workers and task queues (Celery, RQ or similar)
- PostgreSQL and database design
- REST APIs, webhooks, idempotency, retries and signature verification
- Production web scraping: Playwright or Selenium, proxy rotation, rate limiting, session handling, and adapting to changing page markup
- OAuth flows and official third-party APIs
- One-time-code authentication by SMS and email, secrets management, and general application security
Front end
- Solid HTML5, CSS and JavaScript or TypeScript
- Embeddable widgets that work inside third-party pages: iframe and Shadow DOM isolation, CSP, and cross-origin messaging
- Mobile-first, accessible, performance-conscious UI
- Building dashboards and admin interfaces (React or Vue is fine)
AI
- Hands-on experience with the Claude API: prompt design, structured JSON output, image input, and cost and latency control
- Building evals and regression tests for prompts
- Designing around LLM uncertainty with confidence thresholds and human-review fallback
E-commerce platforms
- Shopify app development: Admin GraphQL API, checkout extensions, app billing, and mandatory privacy webhooks
- Working knowledge of WooCommerce (PHP and hooks), BigCommerce and Magento extension development
- Payment gateway concepts: authorize, capture, void and refund flows
Privacy and compliance
- GDPR and CCPA data handling
- Familiarity with marketplace and App Store review requirements
Experience and traits
- 4–7 years of full-stack experience, mid to senior level
- Takes ownership and is comfortable with ambiguity
- Pragmatic: ships a working version, then hardens it
- Designs defensively, assuming third-party sources will change and automated outputs will sometimes be wrong
- Communicates clearly and documents integrations
- Understands conversion-sensitive UX
You will build and extend features across the full stack of a web-based e-commerce product, working directly with the founder. You will own work from idea through production.
Screening and interview exercises (neutral)
Take-home (3–4 hours): Build a Python service that takes a JSON profile, calls Claude for a structured score with a confidence value, and routes low-confidence results to a review queue. Include tests. Design discussion: "A payment authorization is about to expire before a scheduled action completes. How do you detect it and handle it safely?" Front-end task: Build a small embeddable widget that survives a hostile host-page stylesheet, works on mobile, and calls an API without exposing credentials. Debug round: Diagnose a flaky scraper and a webhook that is firing twice.
- Shipped a public Shopify app through App Store review
- Fraud or bot-detection experience
- Docker, CI/CD, and deployment on AWS or GCP
- Experience with append-only logs, hashing, or cryptographic verification
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