Join Blaxel as our first non-founding engineer to define the future of AI infrastructure. You will own the end-to-end developer experience and pioneer "Agentic Experience" (AX), designing interfaces optimized for both human developers and autonomous AI agents. This is a high-impact role building the serverless compute backbone for the next generation of AI companies.
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San Francisco, United States$175K – $250K + 0.1% – 0.5% Equity
DX/AX Engineer at Blaxel - VC-backed AI infrastructure startup
Blaxel is building the 'AWS for AI Agents,' and they need a world-class engineer to define how humans and agents interact with their sub-25ms serverless engine. Backed by a $7.3M seed round led by First Round Capital, this role offers the unique chance to pioneer Agentic Experience (AX) from the ground up. If you've scaled DX at places like Vercel or Fly.io and want to join a founding team in SF, this is your shot to build the infrastructure backbone for the next generation of AI scaleups like Webflow.
Overview
Role overview
Company
Blaxel
Software
Blaxel - First Round Capital-backed AI infrastructure startup
Responsibilities
What you will do
- Design and maintain high-performance CLI, SDKs (TypeScript/Python/Go), and MCP servers that make the platform a joy for developers.
- Architect clever protocols and API interfaces specifically optimized for seamless consumption by autonomous AI agents.
- Relentlessly improve "time to aha moment" by obsessing over API naming, documentation flow, and error message clarity.
Candidate profile
Who this is a fit for
- Proven track record of owning DX at top-tier developer platforms like Vercel, Render, or Fly.io with strong TypeScript skills.
- Deeply fluent in agentic AI patterns with a builder mindset and the high-velocity execution of a former founder.
- Passionate about infrastructure and capable of refactoring complex APIs for clarity while maintaining sub-25ms performance standards.
What makes it remarkable
Why this role is remarkable
- Pioneer a new category by defining the "Agentic Experience" (AX) playbook for how AI agents interact with cloud infrastructure.
- Join a elite team of 6 co-founders with deep infrastructure DNA (previously ForePaaS) and scale a platform already processing billions of requests.
- Backed by $7.3M in seed funding from top-tier investors like First Round Capital and Y Combinator (X25).
Jack & Jill
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
I recruit from Jack’s network and make the intro when I spot a great match.And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
Meet Jack
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How does this work?
Jack's an AI agent for job searching and career coaching. He works for you.
Jill is the AI recruiter working for the company. She recruits from Jack's network.
If it's a match and the company wants to meet you, they'll make the intro. In the meantime, if you'd like, Jack will send you excellent alternatives.
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