Senior Software Engineer

About Bitstack

It all started with an idea in 2021. Initially built to democratize Bitcoin in France, Bitstack has gone from a simple product that invests spare change in bitcoin, to a crypto-native bank bringing a better way to save, spend, and grow money to our 300K+ users. We want to rebuild finance from the ground up to empower people to achieve financial freedom by participating in a more open and inclusive financial system. We’re a small, ambitious team of operators. We believe in moving fast, sweating the details, and creating products people truly love. At Bitstack, you’ll have the opportunity to shape not just our products, but the culture and practices of our entire organization. Bitstack is backed by YC, leading VCs like 13books Capital, Stillmark, Serena, and many more. We are building a product our users love and we are just getting started!

The Role

Bitstack’s engineering team builds the technology platform that powers our mission. We care deeply about writing secure, efficient, well-tested software and shipping incrementally - we deploy every day.

As a Senior Software Engineer, you'll play a key role in shaping how we build. Your focus goes beyond writing code - you'll own the product from design through to release and beyond. We expect you to contribute to product decisions, push back on design where needed, and help shape the user experience. We're looking for builders who bring technical judgement and ownership, proactively identify opportunities, raise the bar for engineering quality, and thrive in an environment with high autonomy and high expectations.

You won’t just execute - you’ll influence how systems evolve and how we operate as a team.

What You'll Be Doing

• Own complex technical initiatives from discovery through production and beyond
• Drive architectural decisions that shape our savings and banking platforms
• Collaborate closely with Product and Design to influence technical direction and trade-offs
• Ship high quality, scalable, reliable systems in a production environment
• Take responsibility for system reliability, security and long-term maintainability
• Proactively identify and lead improvements across infrastructure, security and developer tooling
• Work in a highly compliant environment and contribute to the larger Bitcoin ecosystem
• Raise the engineering bar through strong technical judgement and mentorship

Tech stack

• Backend: Go, Python
• Frontend: Flutter, Dart, TypeScript, JavaScript
• Databases: SQL (basic DBMS knowledge helpful)

What We're Looking For

• 5+ years of professional software engineering experience
• Proven experience owning and delivering complex production systems
• Strong architectural and distributed systems fundamentals
• Experience building highly-available and resilient APIs
• Experience working in cloud-native and microservices environments
• High ownership mindset and ability to operate autonomously
• Strong communication skills and comfort working with stakeholders
• Fintech or regulated environment experience is a strong plus
• Fluent English (French is a bonus)

Interview Process

• Introductory Call (20 min)

An initial conversation with our recruiter to get to know you better and share more details about the role, the team, and how we work at Bitstack

• Engineer call (30 min)

A conversation with one of our senior engineers to assess your technical background and some of the projects you've worked on. This is also an opportunity for us to introduce you to our engineering philosophy and the product ownership responsibilities that come with this role.

• Take Home Task & Task Review Call (60 min)

You’ll receive a practical task to complete in your own time. Once submitted, we’ll schedule a review call to walk through your solution together and explore your thought process in more detail

• System Design (60 min)

A discussion focused on how you approach problem-solving, communicate your ideas, and prioritize decisions. This helps us assess your technical depth and ability to design scalable systems

• Behavioural Interview (60 min)

A conversation centered on your experiences, decision-making, and collaboration style. We’ll discuss real-world scenarios to understand how you navigate technical challenges, teamwork, and stakeholder interactions.

Perks & Benefits

🌎 Work from our office in Paris (Bourse) or Remote (Europe)

🕑 Flexible working hours

👩‍⚕️ One of the best health insurance plans with 100% employer contributions

🏄 Monthly team activities and bi-annual offsites

🍉 Swile meal vouchers

🤑 Competitive salary based on experience & Bitstack stock options

_Please note - we currently can only hire people who are based in the EU with working rights. If you need sponsorship we can provide this in France only.

_Diversity & Inclusion

We hire talented and passionate people from all kinds of backgrounds, we don’t care about your age or where you studied. If you’re excited about the role but your past experience doesn’t match every bullet point in the job description, we still encourage you to apply. What matters most is that you’re a builder at heart, you share our values, and you’re enthusiastic about our mission.