Software Engineer

About Us

\ Sixtyfour AI is a small, fast-moving team building real products for real users. We ship quickly, sweat the details, and give engineers full ownership—from idea to production.

The role

We’re hiring a full-stack engineer who loves taking products from 0→1 and then making them great. You’ll own features end-to-end, work closely with design and founders, and make pragmatic technical decisions that balance speed and quality. If you’ve built things outside of school/work, launched side projects, or tried something entrepreneurial, we want to talk.

What you’ll do

• Build polished, fast product experiences in Next.js TypeScript (accessible, responsive, design-quality UI).
• Design clear backend contracts and APIs in FastAPI/Python for workflows, jobs, billing, and auth.
• Evolve our workflow engine (DAG/state machine): scheduling, retries/idempotency, rate limits, progress, logs, user-visible run history.
• Ship data pipelines and background workers (Celery/queues) with strong observability and alerting.
• Scale and harden on AWS Docker (ECS/EKS or similar), adding Redis caching, pagination, backpressure, and cost controls.
• Implement features end-to-end: DB schema → API → UI, including tests and telemetry.
• Contribute to billing (Stripe), permissions/RBAC, and real-time UX (SSE/WebSockets) for run status.
• Hold a high bar for reliability, performance, and UX—instrument everything, measure, and iterate.
  
  

You’ll thrive here if you have

• Proven ownership: you’ve shipped projects end-to-end (products, startups, open-source, freelancing, apps with users).
• Strong backend Python (FastAPI preferred): API design, testing, error handling, schema/versioning.
• Cloud containers: deployed/operated with Docker and a major cloud (AWS preferred: ECS/EKS/Lambda, SQS, CloudWatch).
• Workflow/job systems experience: queues, retries, idempotency keys, scheduling, and run histories.
• Data stores: comfortable with Postgres schema design and Redis (caching, rate limiting, locks).
• Performance mindset: RSC/Server Actions, data-fetching patterns, bundle/TTFB tuning, DB query perf.
• Production observability: logs, traces, metrics (e.g., OpenTelemetry, Sentry, Langfuse) and pragmatic on-call.
• Security hygiene: PII handling, secrets, JWT/session auth, CSRF/CORS, least-privilege access.
  
  

Nice to have

• Next.js App Router, RSC, Server Actions, edge/runtime primitives (Vercel/CloudFront).
• Prisma/Drizzle; tRPC or GraphQL; Zod/JSON Schema; feature flags/experimentation.
• Real-time UX (WebSockets/SSE), optimistic updates, background revalidation.
• Celery/RQ, event sourcing, or state-machine libs (Temporal, Dagster, Prefect, XState).
• Stripe (subscriptions, metered usage, webhooks) and customer-visible billing pages.
• CI/CD (GitHub Actions), IaC (Terraform), lightweight cost/perf dashboards.
• Search/retrieval (OpenSearch/Elasticsearch) and simple relevance tuning.
• Testing: Playwright (e2e), Vitest/Jest, pytest; accessibility checks.
  
  

How we work

• Ownership > bureaucracy: small team, big impact.
• Speed with quality: ship, measure, iterate.
• Customer-obsessed: polish the details that matter.
  
  

Interview process

• Quick screening call (mutual fit role context).
• Take-home assessment (focused, practical).
• Code walkthrough (discuss decisions, trade-offs, and improvements).
• In-person paid trial week (work with us on real problems; compensated).
  
  

What to include when you apply

• A few links that show initiative and ownership: GitHub, product pages, demos, write-ups, or anything you’ve shipped.
• A short note on a 0→1 project you led: goal → constraints → your decisions → outcome.