Senior Backend / Platform Engineer

Responsibilities

• ● Event store - Append-only PostgreSQL with tamper-evident hash chaining, real-time event distribution, agent replay and recovery, schema versioning.
• ● Cryptographic signature infrastructure - Key management, signature verification on all agent events, approval chains for external actions.
• ● Workflow Constraint Engine - The gateway that verifies authorization before any external action (email, payment, API call) proceeds.
• ● PII Vault & GDPR compliance - Isolated, encrypted storage for personal data. Right to erasure. Data residency per region.
• ● Multi-tenancy - Row-level security, tenant isolation across all data stores, tenant-scoped LLM API keys.
• ● Authorization (Cerbos) - Attribute-based access control for agents and humans. Deterministic policy evaluation - LLMs never make auth decisions.
• ● MCP security layer - Authentication, capability-based scoping per partner, and rate limiting for the Model Context Protocol endpoint.
• ● Database architecture - PostgreSQL schema design, indexing strategy, performance tuning, read replica topology.
• ● + years experience with Python and/or TypeScript in production.
• ● + years designing backend platforms for production systems.
• ● Strong systems design skills - this is the primary requirement. You think in boundaries, contracts, failure modes, and scaling characteristics.
• ● Deep PostgreSQL knowledge - RLS, indexing tradeoffs, event sourcing patterns, schema evolution.
• ● Strong application security architecture skills: encryption models, key management, auth patterns.
• ● Strong code review skills for security-sensitive AI-generated code.
• ● Nice to have:
• ● Cryptographic primitives in production (digital signatures, hash chaining, application-layer encryption).
• ● Event streaming platforms (Kurrent, Redpanda, Kafka).
• ● SOC 2 or GDPR compliance engineering.
• ● Fintech or regulated-environment background.