Senior Fullstack Engineer – Ruby on Rails (Freelance, Remote)
Contract Type: Freelance
Commitment: Full-time
Location: 100% Remote
About the Role
Currently looking for a Senior Fullstack Engineer with strong experience in Ruby on Rails and modern JavaScript frameworks. If you’re passionate about building scalable, well-structured web applications and enjoy working in collaborative, high-impact teams, this is a great opportunity.
This is a freelance, full-time role with the flexibility to work from anywhere.
What You’ll Be Doing
Build, maintain, and evolve scalable web applications using Ruby on Rails.
Develop modern, responsive front-end interfaces with React (or similar), optimizing for performance and usability.
Participate in code reviews and maintain high standards for testing and code quality.
Mentor junior engineers and contribute to team-wide knowledge sharing.
Work closely with design, product, and engineering leads to understand business needs and deliver long-term, scalable solutions.
Contribute to fostering a collaborative and supportive engineering culture.
Who You Are
6+ years of experience in fullstack development.
Strong back-end development skills in Ruby on Rails.
Proficient in modern JavaScript frameworks such as React, Vue, or Angular.
Solid understanding of HTML5, CSS3, and JavaScript fundamentals.
Comfortable with Git workflows and collaborative development.
Experienced in writing tests (RSpec, Capybara) and following TDD/BDD practices.
Knowledge of AWS services like S3, EC2, CloudFront, etc.
Experience building and consuming RESTful APIs in SaaS environments.
Familiar with OOP, SOLID principles, and common design patterns.
Strong grasp of both relational (PostgreSQL) and NoSQL databases.
Bonus Points For
Experience with Sidekiq for background processing.
Familiarity with CI/CD tools (e.g., Capistrano, GitHub Actions).
Experience working with Agile methodologies.
Strong interest in psychology, health, or human behavior.
Native-level Spanish and fluent English.
Exposure to monitoring/logging tools (Datadog, Sentry, New Relic).
Strong communication skills and ability to work independently and proactively.
Experience engaging directly with stakeholders or clients.
What’s Offered
Freelance contract (long-term potential)
Full-time hours with schedule flexibility
Fully remote – work from wherever you do your best work
Competitive freelance compensation
A supportive, mission-driven environment