Senior / Staff Full-Stack Engineer (Node.js + AWS)

Nasze wymagania: 7+ years of experience building and shipping production systems as a full-stack engineer Strong backend expertise in Node.js and TypeScript — not just building APIs, but designing systems that stay correct under load and failure Strong frontend skills with React, including the ability to build polished, production-ready product interfaces without depending on a separate frontend team Solid understanding of distributed systems: consistency, state transitions, concurrency, retries, failure handling, and eventual consistency trade-offs Proven experience building stateful, event-driven systems where correctness matters Hands-on experience with AWS in production, especially Lambda, API Gateway, SQS/SNS, EventBridge, IAM, CloudWatch, RDS, and serverless architecture patterns Strong experience with Infrastructure as Code, ideally AWS SAM and CloudFormation Strong PostgreSQL skills, including schema design, transactions, indexing, migrations, and performance tuning Experience designing systems with idempotency, auditability, and deterministic execution built in from the start Ability to debug and stabilize production systems end-to-end — across application code, infrastructure, data, and runtime behavior Strong grasp of observability, monitoring, logging, alerting, and incident response Good judgment around security, reliability, and cloud cost, with the ability to make pragmatic architectural trade-offs Ability and willingness to own features end-to-end — from product shaping to implementation, deployment, and post-release accountability Comfortable operating in a high-trust, high-autonomy environment with very little hand-holding Strong product and engineering judgment — you ask the right questions early, and you do not need heavy process to move fast responsibly Comfortable using LLMs, coding agents, and modern AI tooling as part of your development workflow Fluent English and Polish, written and spoken Mile widziane: Experience in payments, fintech, ledgering, settlement, or transactional systems Experience with document workflows, approvals, or multi-party business processes Experience working on systems of record or products with strict audit/compliance expectations Experience at an early-stage startup or in a small, high-talent engineering team Experience building products where reliability and system correctness matter more than shipping surface-level features O projekcie: You will own features end-to-end — from the React component a merchant clicks to the Lambda function that settles their transaction to the AWS infrastructure that keeps it all standing. No handoffs between "front" and "back". No waiting for someone else to unblock you. This is a high-trust, high-autonomy role. You'll work directly with the founding team, your decisions will ship to production fast, and yes — you'll be on the hook when something breaks. We're not looking for someone to fill a seat. We're looking for an engineer who gets it — who sees a distributed system and immediately starts asking the right questions about state, consistency, and failure modes. Someone who ships and takes pride in what they ship. Zakres obowiązków: 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 — architecture decisions, 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 Oferujemy: Competitive B2B compensation based on experience Equity — own a piece of what you build Fully remote work in an async-first environment Direct collaboration with the founding team High autonomy and fast decision-making Small team, outsized impact Work on technology that is genuinely novel End-to-end ownership across product, systems, and production Protocols don’t get built by committees. They get built by small teams who understood the problem before anyone else did