Tech Stack
Job Description, Responsibilities & Requirements
About the Position
Senior Fullstack Developer - Freelance (Ruby on Rails & React)
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We are looking for a Senior Fullstack Developer to join our team on a freelance basis, focusing on Ruby on Rails and React for a B2D (business-to-developer) SaaS platform.
The Project
Some products you use every day without ever seeing them. This is one of those.
Our client is a well-established B2D SaaS platform - real-time infrastructure that moves billions of messages a day for developers around the world. Live chat, dashboards, collaborative apps, state synchronization: if it updates in front of your eyes, there's a good chance technology like this is running underneath.
Responsibilities
- Take features from a loose concept to shipped and monitored in production - dashboards, billing UIs, documentation platforms, developer-facing tools.
- Use the product yourself and fix the frustrations you'd want fixed.
- Propose what should be built, not waiting for a roadmap to tell you.
Requirements
- A fullstack craftsman: Strong in Ruby on Rails and React, comfortable moving across the stack - from complex dashboards to sleek documentation platforms.
- A DevEx champion: Natural empathy for other developers and genuinely care about the developer experience of the tools you build.
- Comfortable with ambiguity: Thrive when the brief is vague. Identify problems, propose solutions, and ship with minimal hand-holding.
- An owner: See features through their entire lifecycle - from the first line of code to the final metric in production. Quality issues that surface after release are still yours.
- A proactive communicator: Give realistic estimates, meet your commitments, and speak up early if a timeline is at risk.
- Fluent with AI coding assistants: The team uses them actively for planning, prototyping, and iteration - you should too, while owning the correctness and quality of everything that ships.
- Design and UX intuition: Notice when a flow feels wrong and you're not afraid to say so.
Tech Stack
- React + TypeScript on the frontend
- Ruby on Rails on the backend
- Some Node/TypeScript services
- PostgreSQL underneath
Nice to Have
- Experience building developer-first products or working on B2D platforms
- Experience with products grown through product-led growth (PLG)
- Background in real-time, messaging, or infrastructure-adjacent products
How the Collaboration Works
This is a freelance engagement through the Monterail Tech Network - you work with us on a B2B basis, embedded in the client's team, with Monterail handling the partnership side. Read more about what freelancing with us looks like at Monterail Tech Network.
We Offer
- Freelance engagement with flexible hours
- Work with a well-established B2D SaaS platform
- Opportunity to work with cutting-edge technology
About the Company
We’re an official Vue.js partner, which means Monterail puts a lot of effort into continuously learning and building meaningful products with Vue. Looking for a job as a Vue.js developer? Check out our Vue.js openings.
Send us your resume - and if you've built anything for developers before, we'd love to hear about it.
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