Senior Full-Stack Software Engineer

About the role

Welcome is a travel tech startup founded in Athens in 2015, offering personalised in-destination travel services such as transfers, sightseeing trips and local information. As a Senior Full-Stack Software Engineer you will join one of its product teams and build solutions for its users, focusing mainly on backend engineering while also contributing to the frontend to deliver complete features. You will work in a cross-functional team reporting to the Product Manager and collaborating with designers and engineers, owning features end to end.

Key responsibilities

• Build and maintain backend services, APIs and integrations, ensuring reliability, performance and data integrity.
• Deliver features across the stack, contributing to the frontend using existing components and patterns.
• Collaborate with Product Managers, designers and engineers to shape solutions and make technical trade-offs.
• Own testing, release, production monitoring and follow-up improvements for delivered features.
• Improve the codebase through refactoring and code reviews, and take initiative to improve team processes.
• Use AI coding tools (Claude Code and GitHub Copilot) and validate generated code for correctness, security and maintainability.

Required profile

• 6+ years of experience building and maintaining production applications, with strong backend expertise.
• Experience with Ruby on Rails or another modern backend framework, and willingness to work with Rails.
• Practical experience with React or another modern frontend framework, and willingness to contribute across the stack.
• Ability to understand and extend existing codebases, with solid debugging, maintainability and Git practices.
• A strong ownership mindset: driving work to completion, communicating progress and risks, and improving how the team works.
• Experience using AI coding tools and the ability to evaluate their output critically.

Required skills

• Ruby on Rails and React; Angular components in the Driver app may also be used.
• API design, relational databases and SQL, with PostgreSQL or a comparable database.
• Familiarity with search engines, background job processing and automated testing (Elasticsearch, Sidekiq, Minitest, Playwright).

What we offer

• Vibrant work environment and flexible work-from-home policy.
• Tools needed to perform daily tasks and a learning and development personal budget.
• Private insurance plan and 4 extra PTO days per year.