THE ROLE
We are looking for a driven engineer to join our growing railway systems team. You'll be at the heart of delivering mission-critical software for train control systems — working to the highest safety standards (SIL2) and directly shaping how millions of passengers travel safely every day.
This position is open across our offices in Lisbon, Coimbra, Viseu, and Porto.
WHAT YOU'LL DO
- Design, develop, and validate PLC-based software for safety-critical railway applications, following EN 50657 standards up to SIL2.
- Apply your railway domain knowledge across the full lifecycle of the train control systems — from requirements through to integration.
- Collaborate with cross-functional teams (Systems, V&V, Safety) to ensure software quality and traceability throughout development.
- Produce and review technical documentation including Software Design Specifications, Software Architecture Specifications, and safety cases to SIL2 requirements.
WHAT WE'RE LOOKING FOR
- Minimum 2 years of experience in the railway domain, specifically in Train Control and Management Systems.
- Hands-on PLC programming experience.
- Proven track record delivering software up to SIL2 (EN 50657 or equivalent).
- You take ownership — you don't wait to be told there's a problem; you raise it and help solve it.
- Continuously improve your craft — staying current with railway standards, tooling, and best practices, and sharing knowledge across the team.
- Strong written and verbal communication in English; French is a nice to have.
HOW YOU CAN INSPIRE
- You adapt fast and turn sharp, critical thinking into good decisions for the project
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You are genuinely curious and challenge what needs to change and make bold calls
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You see AI as the biggest shift of this generation and you want to be part of shaping it
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When there is no map, you start drawing one rather than waiting for someone else to
WHAT WE OFFER
We invest in the people who make it all possible. Here's what that looks like in practice.
- Private health insurance
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Employee Assistance Programme (mental health, legal, financial support)
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Home office support
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Extra holidays: 2 additional days after year one, more as time goes on
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Extra parental leave: 2 additional months fully paid
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Gradual return-to-work support: We'll help you ease back from long breaks
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Sabbatical programme for long-term employees
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Training, mentorship, and growth opportunities: we'll invest in where you want to go next
ABOUT CRITICAL SOFTWARE
Every day we work on missions across industries as diverse as aerospace, space, defence, transport, telecoms, government, energy, finance, and healthcare. Building better and safer isn't a slogan. It's how we show up in the world.
Critical Software is a proud Benefit Corporation: a for-profit business legally committed to positive impact on society, workers, the community, and the environment — in addition to profit.
We are an equal opportunity workplace. If you need any adjustment in your recruitment process to show us what you can do, please let us know.
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