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Senior Fullstack Developer - Freelancer (Ruby on Rails and TypeScript)

Monterail Gdańsk, Pomeranian Voivodeship, Poland • Athens, Attica, Greece


No Relocation

Posted: April 24, 2026

Job Description

We’re looking for a Senior Fullstack Developer - Freelancer


What We’re Looking For

    • A Full-Stack Craftsman: You are an expert in Ruby on Rails and TypeScript, capable of building everything from complex dashboards and billing UIs to sleek documentation platforms.
    • The "DevEx" Champion: You have a natural empathy for other developers. You’ll develop deep knowledge of our platform (Pub/Sub, Chat, LiveSync) and use the product yourself to gain a first-hand understanding of the developer experience.
    • Comfortable with Ambiguity: You thrive in high-level vagueness. You can take a feature from a loose concept to a shipped product with minimal hand-holding, identifying problems and proposing solutions independently rather than waiting for a roadmap.
    • Accountable & Reliable: You take pride in high-quality, well-tested code. You meet your delivery commitments, provide realistic estimates based on technical complexity, and communicate proactively if a timeline is ever at risk.
    • An Owner: You monitor what you build in production and take personal ownership of quality issues. You see a feature through its entire lifecycle, from the first line of code to the final metric.

What do we mean by freelance?

We’re looking for a Senior Fullstack Developer - FreelancerWhat We’re Looking ForA Full-Stack Craftsman: You are an expert in Ruby on Rails and TypeScript, capable of building everything from complex dashboards and billing UIs to sleek documen...

Additional Content

We’re looking for a Senior Fullstack Developer - Freelancer


What We’re Looking For

    • A Full-Stack Craftsman: You are an expert in Ruby on Rails and TypeScript, capable of building everything from complex dashboards and billing UIs to sleek documentation platforms.
    • The "DevEx" Champion: You have a natural empathy for other developers. You’ll develop deep knowledge of our platform (Pub/Sub, Chat, LiveSync) and use the product yourself to gain a first-hand understanding of the developer experience.
    • Comfortable with Ambiguity: You thrive in high-level vagueness. You can take a feature from a loose concept to a shipped product with minimal hand-holding, identifying problems and proposing solutions independently rather than waiting for a roadmap.
    • Accountable & Reliable: You take pride in high-quality, well-tested code. You meet your delivery commitments, provide realistic estimates based on technical complexity, and communicate proactively if a timeline is ever at risk.
    • An Owner: You monitor what you build in production and take personal ownership of quality issues. You see a feature through its entire lifecycle, from the first line of code to the final metric.

What do we mean by freelance?

We’re looking for a Senior Fullstack Developer - FreelancerWhat We’re Looking ForA Full-Stack Craftsman: You are an expert in Ruby on Rails and TypeScript, capable of building everything from complex dashboards and billing UIs to sleek documen...