Founding · Engineering

Senior Engineer

Hold the technical bar at 100x scale. Stay deep in the code while owning the architectural calls that decide whether Halcy works at our next order of magnitude.

Apply €120,000–200,000 · 1–3% equity · flexible location

Why Halcy?

Halcy is the platform for travelling with the people you love. Inspiring the initial idea. Co-creating the adventure with your group. Mapping it to the global travel ecosystem. Executing on it for you. Assisting you throughout the journey. Turning it into the memories that seed the next trip.

We want to bring more adventure into people's lives. We're looking for someone who shares that ambition, and who's excited to help build the company that delivers it.

Who you (probably) are

High on curiosity. Low on patience.
High on autonomy. Low on ego.
High tolerance for complexity. Low tolerance for repetition.
Suspicious of process. Religious about pace.
Already builds with agents, and has opinions about how to do it well.

What you (ideally) bring

Must have
5+ years building production systems, including at least one tour as the senior-most engineer in a small team. You've felt the weight of being the person who knows what could break.
Deep TypeScript across the stack (React + Node or Deno) and the judgment to make architectural calls without a senior peer to bounce them off.
Shipped AI-heavy products to real users. Fluent in tool-use orchestration, multi-model gateways, prompt evaluation, and the cost mechanics of running LLMs in production. We run Anthropic and Gemini side by side; you should have opinions on this.
Scar tissue from at least one of: real-time multiplayer at scale, payments and bookings (Stripe + a travel or marketplace stack), or RLS-heavy Postgres at hundreds of tables. Bonus for two.
Bonus
Mobile delivery experience - Capacitor, React Native, or native. We ship to App Store and Play Store and you'd own the build pipeline.
Pragmatic on observability, security, and ToS edges. You spot what's missing before it bites.
Track record of levelling up engineers around you.

What you will (mostly) do

Hold the product vision in your head and translate it into the technical bets that make it real. Your job isn't to ship features off a backlog - it's to figure out which problems are worth solving and to solve them well.

Own the architectural calls that decide whether Halcy works at 100x current load. Concurrency, AI cost, collaborative state, content delivery on mobile.

Stand up the operational floor. Observability, error tracking, end-to-end coverage on critical user journeys, structured logging, alerting, runbooks.

Build the speed infrastructure that lets the team ship faster as it grows. CI that catches problems before prod, preview environments, automated migrations. The kind of investment that compounds, without adding approval steps.

Stay deep in the code. We expect you to ship with your own hands every week, alongside the founders. Architecture without keyboard time decays fast at our stage.

Set the bar for our next ten engineering hires. JD, interview loop, onboarding.

Be the operational compass. Flag what three founders can't see from the inside, early enough to be cheap to fix.

Benefits

Salary €120,000–200,000, calibrated to experience.
Equity Meaningful equity: 1–3%, four-year vest with one-year cliff.
Location Flexible working location.
Ownership Real ownership over a domain from day one.
The work An opportunity to solve a universal and meaningful problem.

Apply

Apply here - we respond to every application within 5 working days.

What's your full name?

Where can we email you?

Where can we find you on LinkedIn?

GitHub, portfolio, or writing - optional but appreciated.

Optional. Pick the one you'd most want us to read.

Impress us - tell us about something you built or shipped that you're proud of.

Links to artifacts welcome.

Any questions for us?

Read our cultural principles →