Senior Fullstack Engineer (ReactJS, NodeJS)

What will you do?

• You'll design and build user-facing features end to end – React frontends, the Node.js services and BFF layers behind them, and their interactions with data stores and third-party APIs.
• You'll own technical direction in your domain: you'll break down large, fuzzy problems into shippable increments and make the architecture calls that come with them.
• You'll partner with Product Managers and Designers early, challenging requirements and shaping scope before a line of code is written.
• You'll support reliable databases and APIs for real-time automated decision-making.
• You'll deploy your software using industry-standard tooling like Kubernetes clusters, and Lambda functions. 
• You'll investigate and resolve production issues by analyzing code, data, and system behavior, then propose and implement timely fixes to minimize user impact.
• You'll care deeply about security in everything you do and constantly raise the baseline of how we defend our users' data against external threats and themselves.
• You'll implement robust automated test suites across the test pyramid to ensure high quality and a low failure rate of delivered code.
• You'll mentor mid-level engineers, give high-quality code review feedback, and act as a go-to person for engineers who lean more heavily to one side of the stack.
• You'll have huge creative freedom and the ability to put your mark on the project – and you'll take ownership and responsibility for what you do.
• You'll have a lot of chances to develop your skills as well as learn a lot about how tech business is done in the US.

We might be a match if you…

• Have at least 5 years of hands-on commercial experience building web applications, with real depth on both sides of the stack – React, Node.js, JavaScript, and TypeScript.
• Have designed and shipped production services, not just consumed them – you're comfortable with API design, microservices, and system design patterns.
• Possess a good, practical knowledge of at least one relational database system, e.g. PostgreSQL/MySQL/SQL Server.
• Have experience implementing the test pyramid (unit, integration, e2e tests).
• Are an independent problem-solver who's comfortable with ambiguity and knows when to ask instead of guess.
• Can lead discussions and decisions regarding software design and architecture, and explain the trade-offs to technical and non-technical audiences alike.
• Can demonstrate responsibility, accountability, and a strong sense of ownership in delivering high-quality work.
• Utilize good security practices effectively.
• Enjoy making other engineers better – through code review, pairing, and mentoring.
• Show readiness to learn and expand your skill set as required by ongoing projects.
• Have a sense of humor – seriously, it matters here.
• Have a good command of English (written & spoken).
• Are available to work in different timezones – we prioritize everyone’s personal time and work-life fit, but since we work across Poland and the US (Austin, San Francisco), occasional evening meetings may be necessary (on average 2 days per week). 

What you'll be using after joining us

TypeScript, Node.js, Nest.js,

PostgreSQL and other data stores,

Docker and container-based deployment technologies (e.g. Kubernetes/Fargate),  

Grafana, Prometheus, Coralogix for monitoring, 

AWS for infrastructure,

Automated software testing on module/integration/system levels, 

AI tools (Devin, Devin Desktop, Claude). 
You will get extra points for:
• Experience with data analysis and BigQuery, 
• Real AI use case production experience,
• Experience mentoring engineers or leading a small team.

Recruitment process:

• Send us your CV – it's the best way for us to get to know you.
• Meet Gabi, one of our Recruiters.
• Complete a 30-minute one-way interview.
• Join a Live Coding session with our Senior Engineers.
• Have a chat with your potential Engineering Manager.
• Meet on the final stage with Marcin and Alicja.
• and... welcome aboard! 👋