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Senior Developer, Backend - Core Payments

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Fullscript

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Location:
Canada , Ottawa

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Contract Type:
Not provided

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Salary:

Not provided

Job Description:

We are currently looking for a senior backend developers who want to build a platform to create rich, stable, and compelling experiences for our users. Fullscript is written with Ruby on Rails, and our Ruby Engineers build and maintain our internal GraphQL API. They work directly with our front-end engineers to build out functionality on the Fullscript platform. On the front end, we’re using React, TypeScript, and Apollo to create top-notch experiences for our users. Our team cares about doing things well, and about the developer experience on the team. We host in-house training on all sorts of topics, from React all the way through to Kubernetes. Fullscript is a place where you’ll be encouraged to learn, mentor, and grow. On the Core team, you will work with the financials, contributing to projects related to payments, checkouts, or our e-commerce engine.

Job Responsibility:

  • Take ownership and responsibility for building, shipping, testing, deploying, and maintaining checkout iterations & implementing business logic our e-commerce platform core
  • Build scalable backend applications to support the growing needs of the business
  • Review pull requests, mentor, and be an advocate for high-quality code that makes future development faster, easier, and better
  • Scope, plan projects, and work with other developers (front-end and back) to implement them
  • Give input on high-level architecture decisions and communicate those decisions
  • Solve performance issues within our checkout and payment systems
  • Other duties determined by the company from time to time

Requirements:

  • You are a passionate software engineer who cares about your craft
  • Experience with Ruby or Ruby on Rails
  • Experience making meaningful contributions to the scalability and reliability of complex systems
  • Experience architecting simple solutions to complex problems
  • You write tests and understand their value
  • You have a desire to learn and are open to feedback
  • Understanding of design patterns and clean code
  • Experience mentoring or coaching junior engineers

Nice to have:

  • Experience scaling or working on high-scale web applications
  • Past experience working in e-commerce or health-tech sector
  • Worked with Stripe or other payment providers
  • Experience with React and GraphQL or similar technology
  • Experience working with Javascript or JS frameworks (React, Vue, AngularJS, Next or similar)
  • Understanding of CSS frameworks like Bootstrap, as well as CSS preprocessors
What we offer:
  • Generous PTO and competitive pay
  • Fullscript’s RRSP match program for financial health
  • Flexible benefits package and workplace wellness program
  • Training budget and company-wide learning initiatives
  • Discount on Fullscript catalog of products
  • Ability to work Wherever You Work Well

Additional Information:

Job Posted:
January 03, 2026

Employment Type:
Fulltime
Work Type:
Remote work
Job Link Share:

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