Senior Rails Engineer

Mon Ami (HearstLab); United States; Remote; USD 120,000 - 180,000; Full time

Benefits offered by this job

Health insurance

15 days PTO (increasing to 20 days) +

401K

Disability insurance

FSA

HSA

Generous paid family leave

Job summary

Mon Ami (HearstLab) seeks a Senior Engineer to design, build, test, and maintain core software used by customers daily. You will own a defined area of the codebase and mentor 1–3 junior engineers.

The stack includes Ruby on Rails, Bootstrap, Stimulus, and Postgres. You will work with product managers in an Agile team, applying strong engineering practices and exploring AI-assisted tools to improve productivity and code quality.

Qualifications

• 3–5+ years of experience as a mid-level engineer at a fast-growing technology company.
• Fluency with Ruby on Rails, Stimulus, JavaScript, and SQL/Postgres.
• Strong coding practices: refactoring, data design, and testing.
• Experience mentoring 1–3 junior engineers.
• Comfort with Agile methodologies and third-party integrations.
• Hands-on AI development tool experience (Claude Code or Codex).

Responsibilities

• Own a defined area of the codebase and ship Rails features end to end.
• Write and review code with Rails, Bootstrap, Stimulus and Postgres.
• Mentor a team of 1–3 junior engineers and collaborate with product managers.
• Promote agile practices and maintain a healthy test-to-code ratio.
• Evaluate third-party APIs and integrate them effectively.

Skills

Ruby on Rails

Stimulus

JavaScript

Bootstrap

CSS3

Hotwire/Turbo

RSpec

ViewComponent

SQL / Postgres

Git

AI tooling (Claude Code / Codex)

Agile methodologies

Tools

Terraform

AWS

Google Cloud

SQL reporting tools

CI/CD tools

Job description

Mon Ami is seeking a Senior Engineer to design, build, test, and maintain core software relied on by customers daily. You will take ownership of a defined area of the codebase and work closely with product managers and a team of 1–3 junior engineers to deliver impactful projects for public-agency clients. The stack includes Ruby on Rails, Bootstrap, Stimulus, and Postgres. Responsibilities are balanced between coding, code review, data model design, and mentoring.

Responsibilities will include:

• Take ownership of a defined area of the codebase, shipping production-grade Rails features end to end
• Write, review, and maintain code using Rails, Bootstrap, Stimulus, and Postgres (or similar frameworks)
• Support and mentor a team of 1–3 junior engineers, partnering with product managers to deliver projects and develop talent
• Operate with agility and initiative in a small, high-performing team environment
• Apply strong engineering practices, including thoughtful refactoring, careful data design, and disciplined testing (maintaining a 1.4:1 test-to-code ratio)
• Use AI-assisted development tools (such as Claude Code or Codex) to enhance development practices and productivity

You’re a great fit if you:

• Have 3–5+ years of experience as a mid-level engineer at a fast-growing technology company
• Are fluent in Ruby on Rails, Stimulus, JavaScript, Bootstrap, CSS3, Hotwire/Turbo, RSpec, ViewComponent, SQL/Postgres, Git, and SQL reporting tools
• Demonstrate strong engineering practices, including refactoring, data design, and testing
• Are a creative problem-solver who enjoys evaluating and integrating third-party software and APIs
• Have hands-on experience with AI development tools like Claude Code or Codex, and understand when to use each
• Are comfortable working within Agile methodologies
• Bonus: Experience with Terraform, AWS, Google Cloud, HIPAA-regulated products with PHI, or multi-tenant SaaS architecture

Total Compensation

Benefits include:

• Health insurance
• 15 days PTO (increasing to 20 days after two years) and sick leave
• 401K, disability insurance, FSA, and HSA
• Generous paid family leave
• The opportunity to do meaningful work with a respectful and kind team