Senior Software Engineer

Location: Sofia, Bulgaria

About us

We are EnduroSat! A fast-growing space scale-up at the forefront of satellite innovation, specializing in advanced software-flexible satellites for commercial, governmental, and scientific endeavors.

• This is more than a job, it’s a mission

  We are making space universally accessible and redefining what's possible.

• We get things done

  We take ownership of what we do and we work hard to make a difference.

• We are fearless

  Transparency is our only way forward. We dare to address and resolve issues head-on.

• We learn from our mistakes

  We deliver, take informed risks, and evolve to achieve our goals. We compare with the best version of ourselves

The problem you'll work on

The SpaceOps Platform operates hundreds of EnduroSat satellites, many of them taking decisions autonomously, without a human in the loop. When the platform gets it wrong, missions are lost. When it gets it right, our customers can do things in space that no one else can deliver. There's no big playbook to copy from, and you'll own real surface area from day one.

We're hiring an AI-leveraged engineer: someone who orchestrates AI agents, prompting, and reviews as a core part of how they design, build, and debug, and who knows when AI output is wrong, insufficient, or unsafe to ship. Both halves are non-negotiable. We're technology-agnostic on language; we care about how you think and what you've shipped.

Some of your daily tasks will include

• Design, build, and maintain back-end services and APIs (REST and WebSocket) for the SpaceOps Platform
• Build cloud-native solutions and run them at scale on AWS, GCP, or Azure
• Model and manage data stores (particularly NoSQL) for satellite telemetry and operational data
• Implement and uphold security, authentication, and permissions (OAuth2, OIDC)
• Orchestrate AI tooling, like Claude Code, and build agentic workflows across design, implementation, review, and debugging, while keeping a critical eye on every output, improving the harness after each mishap
• Own features end-to-end: from requirements through production deployment and post-launch operation

What we look for

• 5+ years of professional back-end or full-stack software engineering experience
• A demonstrable AI-leveraged workflow with strong judgement: comfortable orchestrating AI agents and prompting daily, and able to spot when AI output is wrong, hallucinated, or unsafe to ship
• Strong proficiency in at least one of: Node.js, C#, Java, or Python (we're language-agnostic, bring your strength)
• Hands-on experience with at least one major cloud provider (mandatory): AWS, GCP, or Azure
• Strong NoSQL database design experience
• Proficiency in REST and/or WebSocket API design and development
• Experience with security mechanisms and permissions management (OAuth2, OIDC, or equivalent)
• Bachelor's degree in Computer Science, Engineering, or equivalent practical depth

This role is not for you if...

• You like detailed specs and a stable backlog. A lot of what we work on doesn't have an answer yet; we figure it out as we go.
• You're uncomfortable making calls without complete information.
• You like AI mostly because it makes you faster. We need someone who's just as interested in catching where it goes wrong.
• You want a polished, predictable codebase. Ours isn't, and parts of it won't be for a while.

If those sound like a relief rather than a warning, keep reading.

What you're signing up for

If you're an engineer who's faster and more dangerous with AI than without it, and you're tired of teams that either ban it or rubber-stamp its output, this is a team that takes both halves seriously.

• Real engineering challenges. You'll work on autonomous decision-making for spacecraft we actually operate today, not a research demo.
• AI-augmented engineering, done seriously. We treat AI fluency and AI skepticism as paired core skills, and expect you to raise the bar on both.
• Quarterly objectives, delivery culture. Clear quarterly goals, short feedback loops, and a team that ships.
• Growth and learning. Career progression framework plus our hands-on space education program with international experts.