Backend Architect

Responsibilities:

• Work with AI Lead and own parts of the backend architecture. API design, data modeling, service boundaries, real-time sync, auth, and multi-tenancy. Make the calls whose everyone else's code lives inside.
• Build the real-time and multiplayer layer. WebSocket fanout, presence, conflict resolution, and document sync are the substrates that make the canvas feel live for every user in a workspace.
• Design the data layer with judgment, not defaults. Pick the right store for each workload: relational, document, event log, blob, and cache; and own the schemas, migrations, and consistency model.
• Ship into our TypeScript monorepo. API, auth, database, and real-time services all live in one codebase; you'll work across all of them and set the patterns for how they fit together.
• Own auth, orgs, and permissions. Workspaces, sharing, roles, and auditing are the things that make us safe to use inside a company.
• Build AI-friendly backend primitives. Streaming endpoints, long-running agent calls, idempotency, and cost attributionthe AI features will call into your APIs, and you'll make sure they can.
• Set the technical bar for backend engineers. Code review, design review, and the patterns the rest of the backend team learns from.

Requirements:

• 10+ years of software engineering experience, with significant time as a hands-on backend architect or senior backend engineer. This is a deeply hands-on role; you'll write the code, not just review it.
• Production TypeScript experience in large, complex codebases you've shipped non-trivial backend systems in TS, ideally in a monorepo, and have strong opinions on how to structure a TS backend at scale.
• Shipped a collaborative or real-time backend in production. WebSocket fanout, presence, document sync, and conflict resolution (CRDT, OT, or equivalent) that you've owned in a live multi-user product.
• Strong database fundamentals. Schema design, indexing, query performance, transactions, migrations, consistency models. Comfortable making the call between relational, document, and event-sourced approaches based on the workload.
• Multi-tenancy and auth depth: orgs, workspaces, RBAC, sharing semantics, and audit.
• Comfortable with the Kubernetes and Terraform infra surfaces and CI/CD enough to debug, contribute, and design with infra constraints in mind. You don't have to own it, but you can't be helpless around it.
• Architect-level judgment without manager scope. You're the technical anchor, not a people manager.

Nice to Have:

• Experience designing AI-aware backend APIs with streaming responses, long-running agent calls, token-bounded request/response shapes, idempotency for retried LLM ops, and cost attribution per tenant.
• CRDT or OT internals experience (Yjs, Automerge, ShareJS lineage, or having built your own).
• Background shipping canvas, design tool, IDE, or collaborative document backends.
• Experience with observability and reliability engineering at a serious level: SLOs, on-call, and debugging production at scale.