Full‑Stack Engineer

Blue is building the trust layer the AI economy has been waiting for — a protocol for structured, verifiable, multi-party agreements that execute deterministically, leave an audit trail, and work across any system. Think smart contracts, minus the blockchain overhead. Our products are already being built and tested with real integrations: PayNotes, programmable payments with conditional capture, milestone releases, refunds, vouchers, and partner settlement; MyOS, a SaaS orchestration layer for merchants and agents providing cross-platform trust without writing a line of Blue Language yourself.

• 7+ years building and shipping production systems as a full-stack engineer
• Backend expertise in Node.js and TypeScript with system design under load and failure
• Frontend experience with React to build polished, production-ready interfaces
• Knowledge of distributed systems including consistency, state transitions, concurrency, retries, and failure handling
• Proven experience in stateful, event-driven systems where correctness matters
• AWS production experience with Lambda, API Gateway, SQS/SNS, EventBridge, IAM, CloudWatch, RDS
• Infrastructure as Code experience with AWS SAM and CloudFormation
• PostgreSQL skills including schema design, transactions, indexing, migrations, and performance tuning
• Design for idempotency, auditability, and deterministic execution
• Observability skills including monitoring, logging, alerting, and incident response
• Ownership of features end-to-end with product shaping and post-release accountability
• Comfortable using LLMs, coding agents, and modern AI tooling
• Fluent English and Polish, written and spoken

Nice to have:

• Experience with payments/fintech, ledgering, settlement, transactional systems
• Experience with document workflows, approvals, multi-party business processes
• Experience with systems of record with strict audit/compliance requirements
• Experience in early-stage startups or small, high-talent engineering teams
• Experience with products where reliability and correctness outweigh surface-level shipping

• Design and ship full-stack features across payments, document workflows, and agent orchestration
• Build and maintain stateful systems that demand idempotency, auditability, and safe retry logic
• Own AWS infrastructure including architecture, serverless systems, IaC (SAM / CloudFormation), monitoring, cost, and security
• Work with PostgreSQL-backed services and event-driven components
• Use modern AI tooling (LLMs and coding agents) to accelerate development and experimentation