Sr. Backend Engineer (Node.js/TS) - FT Freelance - Americas

Role Overview

We're building the agentic design platform—an AI chat interface (+API) that lets anyone go from prompt to production-grade visual in minutes. Under the hood we're using Liveblocks.io for sync and storage, Postgres/Supabase for catalog + ops log + jobs + assets, and workers for renders/ML ops.

Responsibilities

Own the realtime and services layer that powers our editor and agents. You’ll design APIs, job queues, and sync/multiplayer primitives, and work with our frontend engineer who will handle the UI/agent surfaces.

What you’ll do

• Design and ship backend services in Node.js + TypeScript (REST/tRPC/GraphQL).
• Implement realtime sync (presence, cursors, ops) over WebSockets; integrate Liveblocks.io or equivalent.
• Build job/worker pipelines for renders & ML ops (BullMQ/Redis, SQS, or Cloudflare Queues).
• Model and query Postgres (via Supabase) for designs, ops logs, snapshots, and usage metering.
• Orchestrate asset flows with Supabase storage (S3); ensure idempotency, retries, and back-pressure.
• Add observability (logs/metrics/traces), testing, and pragmatic docs.

Required Skills

• TypeScript and Node.js in production backends.
• WebSockets/realtime systems and solid API design.
• Postgres data modeling + performance; Redis familiarity.
• Queue/worker patterns, reliability (retries, DLQs), and security basics.
• Strong skills in API architecture design and implementation.
• Ability to work effectively within Pacific Time (PST) and LATAM timezones.

Nice to Have

• Liveblocks.io (or OT/CRDT concepts) for multiplayer sync.
• Cloudflare Workers/Queues, serverless/Vercel, or containerized services.
• Web Workers concepts (for client/edge offload) and perf debugging.
• Graphics/render pipelines (WebGL/Canvas) awareness to collaborate on render jobs.
• AuthZ/AuthN (e.g., Clerk), rate limiting, and usage metering.

What makes this exciting

• Small senior team, high ownership.
• You’ll define the backbone that lets agents and humans co-create in realtime.