Full-Stack Engineer (Frontend Leaning)

About the role

Ethos, a life insurance technology company, is looking for a frontend-leaning Full-Stack Software Engineer to build scalable platform services and systems. You will work closely with other engineers to build and ship key features, helping to architect and build internal standards and frameworks. The role is hybrid, with at least 2 days in the office and 3 days remote per week, and candidates are preferably based in San Francisco or willing to relocate.

Key responsibilities

• Design, build and maintain complex full-stack systems
• Collaborate with engineers, product managers and non-technical stakeholders to develop and ship features
• Design, build and maintain the company's APIs
• Find and solve performance issues
• Take part in code reviews and share best practices with the team
• Write engineering requirements documents

Required profile

• 2-5 years of relevant software engineering experience
• Full-stack experience in JavaScript, TypeScript, Node or Python
• Experience shipping features behind an A/B testing or feature flag platform, such as Optimizely
• Ability to communicate technical specifications verbally and in writing
• Understanding of security, common attacks and defenses
• Solid computer science fundamentals, including data structures and algorithms

Required skills

• Front-end technologies such as HTML, CSS and React
• Optimizing Core Web Vitals and loading speed
• Backend architectural patterns for large, high-scale web applications
• Build system configuration, such as Webpack
• Infrastructure, distributed systems and deployment in high-scale environments with logging and monitoring
• Leveraging agentic coding tools (e.g. Claude Code, Cursor, Copilot)
• Mobile-first responsive styling
• Third-party lifecycle communication platforms such as Iterable, Twilio, Salesforce and Regal