Senior Backend Developer (freelance)

In short

If you're a backend engineer who doesn't just build what's asked, but shapes how it's built, we want to talk. We're looking for someone who can own the technical direction of a project end to end: architecture, infrastructure, trade-offs, and the conversations that come with them. You'd join us on a freelance, time & material basis: you're paid for the hours you actually work on real client projects. Full capacity from the start. The first three months are about figuring out if we're a good match. When things work out, and that depends on the work itself, the project pipeline, and business timing, there's a real path to our core team with a permanent contract and full benefits.

Why intent?

We've been designing and co-creating connected devices since 2008. Wearables, smart audio, health-tech hardware for clients like Oura and BOSE, backed by investors like a16z and Founders Fund. We're 60+ people, fully remote, and AI-native since before LinkedIn influencers discovered the term. We use AI every day, in actual work, not just in company decks. Our backend isn't generic CRUD: it's the cloud spine of physical devices, the layer where firmware meets data pipelines, and where one bad architectural call shows up in a sensor reading six months later.

Who this role is NOT for

If your comfort zone is a well-defined Jira board, clear specs, and someone else making the architectural calls, this isn't going to work. We're not hiring a senior developer who executes well. We're hiring someone who decides what gets built, how it gets built, and why. Someone who walks into a room full of ambiguity and starts creating structure, not waiting for it. If you need a ticket to start moving, if "that's not in the requirements" is a sentence you use often, or if you'd rather not be the one explaining a technical trade-off to a client, we're probably not your people. We're AI-native and we expect you to treat AI tools as a daily multiplier, not a gimmick.

What you'll do

• Own and evolve the backend architecture for IoT projects: data ingestion pipelines, API design, infrastructure decisions
• Make technical trade-off calls and defend them clearly to the team and to clients
• Design and maintain cloud infrastructure on AWS (EKS, Aurora, DynamoDB, Timestream, S3) with production-grade reliability
• Lead technical discussions: RFCs, architecture reviews, post-mortems, because you see the need, not because someone asked
• Mentor other backend engineers, raise the bar on code quality, and set patterns others can follow
• Work side by side with firmware engineers, mobile developers, QA, PMs, and clients
• Use AI tools as part of your daily workflow, not as a party trick
• Challenge product and technical assumptions when something doesn't add up, even when it means a harder conversation

How we work

Fully remote. We have a pet-friendly office in Warsaw and a coworking space in Gdansk if walls and coffee machines motivate you, but nobody will ask why you're not there. Working hours are flexible: most of the team operates between 10:00 and 18:00 CET, and that's when most meetings happen. Evening calls with US-based clients (up to ~20:00) are part of the rhythm, sometimes a couple of times a week, always planned ahead. You'll be part of the Mobile chapter (which covers backend/cloud too) for knowledge-sharing, and at the same time on a project squad led by a PM for day-to-day delivery.

What you'll get

• 90-180 PLN/h net B2B, depending on your experience
• Truly flexible hours: you organize your day
• Fully remote, with pet-friendly Warsaw office + Gdansk cowork if you want them
• Access to our internal knowledge-sharing: tech talks, experiments, side projects
• When the first 3 months work out, and that depends on the work, the project pipeline, and business timing, there's a real path to a permanent contract with a fixed monthly salary, 26 days paid leave, 10 sick days, Saltus medical care, and a training budget
• No sugarcoating: during the freelance period there's no paid leave