Senior Software Engineer

Engain; Phoenix (AZ); On-site; USD 78,000 - 134,000; Full time

Job summary

Engain in Phoenix, Arizona is seeking a Founding Senior Software Developer / AI Engineer to join an early-stage AI startup. You will be instrumental in shaping architecture and leading the development of AI-powered products from the ground up.

We're looking for someone highly technical, ambitious, and excited about solving hard problems. You should have experience with backend systems, AI/LLMs, agents, and model development, plus a track record of owning initiatives in a startup setting.

Qualifications

• Demonstrated software engineering and AI experience.
• Experience with AI systems, agents, and model development.
• Ability to work quickly with ownership in a startup.
• Experience with AI-assisted development tools.

Skills

Software engineering

AI/LLMs

Backend systems

Independent problem solving

AI tools

Startup environment

Tools

Claude Code

Codex

Cursor

Job description

We're looking for a Founding Senior Software Developer / AI Engineer in Phoenix, Arizona to join an early-stage AI startup.

We're looking for someone highly technical, ambitious, and genuinely excited about building AI products from the ground up.

You'd have experience with:

• Software engineering and backend systems
• AI, LLMs, agents, and model development
• Building and experimenting with new AI systems
• Solving difficult technical problems independently
• AI-assisted development, practical experience with Claude Code, Codex, Cursor or similar tools
• Working fast in a startup environment with a lot of ownership

Compensation: $7,000/month - $12,000 depending on experience.

We care a lot about ability, ambition, speed of learning, and how you think.

If you don't match every requirement but you're extremely ambitious, technical, and believe you could become exceptional in this space, we'd still love to hear from you.