Full Stack Software Engineer
Full-Time (Primarily Remote)
Division: Mainstay
Salary: $120,000 - $140,000
Join our team at Mainstay - a division of Lemnis! Lemnis is a public charity dedicated to harnessing transformative change to expand learning for all. We are excited to announce a new opportunity for a Full Stack Software Engineer at Mainstay. We are committed to fostering a collaborative and inclusive work environment where every team member can thrive. If you are passionate about expanding learning for all, eager to make a meaningful impact, and ready to take on new challenges, we would love to hear from you. Apply now and be a part of our journey!
Position Summary
At Mainstay, we believe one conversation can spark a brighter future. Our Engagement Platform makes it easy for colleges and businesses to start and measure conversations that drive action at scale. From our rigorous research methods to our Behavioral Intelligence framework — everything we do is designed to help people take the next step toward achieving their goals.
The engineering team is a group of talented full stack developers, data engineers, data analysts, and AI experts. Engineers collaborate closely with their counterparts in the product team and external stakeholders to build new functionality and enhance existing products to delight our partners and end users. The team is excited to continue tackling new challenges and leverage cutting edge technologies to solve impactful problems.
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Responsibilities:
Strong proficiency across the stack, with production experience in a modern frontend framework (React preferred) and a backend language (Python/Django or Node/TypeScript)
Solid grasp of computer science fundamentals: data structures, algorithms, and system design
Experience writing automated tests and maintaining meaningful test coverage
Familiarity with software engineering best practices (git, CI/CD, code review, PRs)
Experience building and consuming APIs (REST or GraphQL)
Comfortable working with relational databases and writing efficient queries
Strong communication skills with an ability to collaborate cross-functionally
Flexibility, ownership, and a team player mentality
Ship full stack features end to end
Rapidly prototype, develop, and ship server-side and user-facing code every single day
Work across a full stack codebase including a React frontend (TypeScript) and Python (Django) and Node (TypeScript) backend
Own features from product discovery through implementation, testing, and release
Write high-quality, maintainable code
Write clean, well-tested code and the corresponding automated tests
Review peers' code and uphold engineering standards across the team
Refactor and improve existing systems as the product evolves
Keep what you ship stable
You ensure code is reliable and stable once deployed
Monitor, debug, and resolve issues in production
Contribute to CI/CD pipelines and deployment practices
Collaborate across the team working with Engineering, Product, and Design through product discovery, implementation, and testing
Translate product requirements into technical solutions
Share knowledge and mentor through pairing and code review
Qualifications
5+ years of experience as a software engineer in an Agile environment
Preferred Qualifications
You augment your capacity with AI or LLM-powered product and features
Use agentic coding tools (Claude Code, Cursor, Copilot, Codex, or similar) as a daily part of your workflow to plan, write, test, and refactor faster
Apply strong judgment to AI-generated code: you own correctness, security, and architecture, and you can spot when an agent is wrong or hallucinating
EdTech, higher education, or B2B SaaS background
Experience working on partner-facing or customer-facing products
Comfort with ambiguity and a bias toward shipping
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