Senior Software Engineer Full-Stack

Position Summary

The Senior Software Engineer, Full-Stack builds substantial, interactive features inside Onit's enterprise legal operations platform, spanning enterprise legal management, matter management, spend management, and contract lifecycle management. Working across a Ruby on Rails backend and a modern JavaScript frontend, this individual contributor delivers data-dense, accurate, and resilient user experiences that fit seamlessly into the workflows legal teams rely on every day. The role partners closely with design, product, and the architecture team, owning features end to end from API to interface, with a strong focus on edge cases, performance, accessibility, and test coverage.

Key Responsibilities:

• Build substantial, interactive features inside an existing enterprise product, without disrupting the workflows they sit within.
• Implement data visualisations (line charts, comparison tables, range indicators) where the visual encoding carries real meaning and small inaccuracies mislead users.
• Build filtering and comparison controls that update complex views in real time.
• Implement every state the feature can be in: loading, error, empty, and the cases where there is insufficient data to show a comparison at all. These matter as much as the primary path.
• Build and extend Ruby on Rails APIs, consume APIs built by the architecture team, and push back early when a contract does not serve the interface well.
• Work closely with design, matching intent precisely and raising discrepancies rather than approximating.
• Make sure features load asynchronously and never block or slow the workflows they are embedded in.
• Build for accessibility and cross-browser consistency.
• Instrument features so the team can measure how they are actually used.
• Write tests that cover behaviour, including the degraded cases.

Required Skills:

• 6+ years building production web applications, with significant frontend ownership and hands-on backend development.
• Strong backend experience with Ruby on Rails: building and modifying APIs, data models, and services, not only consuming them.
• Strong proficiency with a modern JavaScript framework (React, Angular, or Vue) and solid JavaScript/TypeScript fundamentals, including a real understanding of rendering and state management, not just framework APIs.
• Experience building data-dense interfaces: charts, tables, dashboards, or comparison views where accuracy of presentation matters.
• Experience working inside large existing codebases: reading unfamiliar code, following established conventions, and avoiding regressions.
• Demonstrable care for edge cases, empty states, and error handling, backed by automated tests (e.g., RSpec and frontend testing frameworks).
• Strong collaboration with designers and product managers; asks clarifying questions before building.
• Working proficiency with AI coding tools (e.g., Claude, GitHub Copilot) to accelerate development, debugging, and test writing, with the judgment to review and validate AI-generated code before it ships.