Wrocław, Lower Silesian Voivodeship, Poland Remote (Global)

Monterail is hiring a Principal Software Developer (Ruby on Rails & React) - Freelancer

About the Role

Lead the technical vision for internal platforms by designing and refining system architecture in Ruby on Rails and React. As a Principal Software Developer, you'll operate independently to translate business needs into sustainable, well-structured applications, with a particular focus on admin interfaces and internal tooling used across small to mid-sized teams.

What You'll Do

  • Define and drive the technical roadmap, making strategic decisions that balance immediate needs with long-term scalability
  • Architect and evolve backend and frontend systems with an emphasis on clarity, maintainability, and usability
  • Design and implement comprehensive test suites as a foundational part of development
  • Collaborate with stakeholders to understand requirements and deliver effective, well-scoped technical solutions
  • Identify gaps in current systems and propose practical improvements with clear trade-off analysis
  • Take full ownership of technical outcomes, from concept through implementation and beyond

What We're Looking For

  • At least 8 years of hands-on software development experience
  • Deep proficiency in Ruby on Rails and React, with a track record of leading technical direction
  • Proven ability to work autonomously and bring structure to complex, ambiguous problems
  • Experience building internal tools and admin panels for limited user bases
  • Strong commitment to code quality, testing, and long-term system health
  • Clear communication skills and the maturity to engage with stakeholders at all levels
  • A pragmatic mindset focused on sustainable, thoughtful engineering decisions
Required Skills
Ruby on RailsReactSoftware DevelopmentArchitectureSystem DesignTechnical LeadershipMentoringCode ReviewBest PracticesOwnership Ruby on RailsReactFullstack DevelopmentSoftware ArchitectureSystem DesignEnd-to-End OwnershipRoadmap PlanningTechnical LeadershipProblem SolvingCode Quality
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About company
Monterail
A team of over 130+ experts working together to create meaningful software.
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Job Details
Category fullstack
Posted a month ago