Back-End Engineer at fifthdoor.com (San Francisco, CA)
fifthdoor.com· San Francisco, CA·
Role details
Work type
Remote
Employment
Full-Time
Job description
About Us
Fifth Door unlocks the power of imagination by making it easy for anyone to create, share, and play turn-based games anywhere, with anyone. We exist to inspire connection, creativity, and community through the limitless joy of games.
Create. Play. Anywhere.
About the Role
We are seeking a Back-End Engineer who is passionate about delivering outstanding user experiences that delight our users. This is an opportunity to join a fast-moving, ambitious team where your work will have real impact from day one.
Responsibilities
- Help architect, develop, and maintain the backend for our AI-powered game engine and web applications.
- Collaborate with cross-functional teams to design scalable and secure systems.
- Optimize applications for maximum speed, performance, and scalability.
- Write clean, maintainable, and well-tested code.
- Identify and troubleshoot back-end performance issues.
- Stay current with trends and emerging technologies, bringing ideas back to the team.
Qualifications
Must-Have:
- 3+ years of experience as a backend or full stack engineer or similar role.
- Expert proficiency in a programming language used on the backend, such as Ruby, Typescript, Python, or Golang
- Strong understanding of backend development concepts (e.g. API development, structuring applications, databases, workflows)
- Experience working with databases, both SQL and NoSQL
- Familiarity with modern build pipelines and tools
- Strong interest in AI technologies or experience integrating AI into a product
- Experience working in an agile development environment
- Proficiency using AI tools in development workflows
Nice-to-Have:
- Some familiarity with front-end technologies and working with Typescript and React is a plus.
- Passion for gaming, creative tools, or AI applications.
- Experience with AI prompt engineering.
Benefits
- Competitive salary and meaningful equity.
- Health, dental, and vision coverage.
- Flexible work hours and unlimited vacation policy.
- A collaborative, supportive team environment.
- Opportunity to shape product direction and culture early.
Why work at fifthdoor.com
- Early-stage impact: As one of the first engineering hires, you will shape the product and technical architecture from the ground up.
- Hybrid/Remote flexibility: San Francisco-based with a hybrid workspace; roles are open to remote US applicants as well.
- Competitive compensation: Salary range of $150k–$250k plus 0.10%–0.50% equity (per Y Combinator job postings).
- Founding team culture: Small, tight-knit team (currently 3–4 people) with a focus on creativity, connection, and fun.
- Y Combinator backing: Access to YC's network and resources provides strong startup acceleration support.