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Senior Systems Engineer

Blacksmith · New York City, New York

Location
New York City, New York, United States
Employment
Full time
Level
Senior
Posted
30 April

About this role

About Blacksmith

  • We started by building infrastructure to run CI workloads really fast. Our first product helps companies run GitHub Actions substantially faster and cheaper by owning and operating our own global fleet of bare-metal machines rather than renting generic cloud VMs.

  • Today, we orchestrate tens of millions of Firecracker VMs each month, running CI for 3,000+ companies and hit ~$10M in ARR in less than 2 years. We’ve already more than 5X'd revenue since the start of 2026.

  • We operate thousands of bare-metal machines across multiple regions, regularly schedule 100k+ vCPUs concurrently, and run a petabyte-scale Ceph cluster that we manage ourselves.

  • We’ve raised $58.5M from Seed to Series B, led by Google Ventures (GV) & Peak XV Capital, and we’re intentionally building a small, but exceptional team.

  • Blacksmith was founded by a team with deep systems and scaling experience, including building search/ads infrastructure at Faire, and operating large distributed systems at Cockroach Labs. Our GTM is led by Jon Boyer, formerly Head of Sales at Zapier.

  • We’re now extending the same CI infrastructure into a broader platform: running agent sandboxes at scale and building our own background coding agent on top of it.

You are a good fit if you

  • Have developed and scaled distributed systems and enjoy digging into performance and reliability issues across the filesystem, network, and storage stack.

  • Are comfortable writing and debugging in C, C++, Go, Rust, or Zig, and care deeply about efficiency, correctness, and safety at the systems level.

  • Are excited by the idea of self-hosting and managing infrastructure with build automation and configuration management tools (e.g., Ansible, Puppet, Chef).

  • Have familiarity with distributed storage systems like Ceph or MinIO, or are eager to get hands-on with them.

  • Have 5+ years of software development experience, ideally in performance-critical or distributed environments.

  • Enjoy working in person 5 days a week in NYC with a small, tight-knit team.

  • Thrive in the ambiguity of an early-stage startup and are energized by building from first principles.

Bonus

  • You’ve dabbled in your own side hustles or start-up projects.

  • You’re comfortable creating new processes and iterating on them quickly.

Compensation and benefits

  • Medical, Vision, and Dental insurance.

  • Competitive base + equity.

  • 401K match.

  • Unlimited PTO.

  • Annual offsite.

  • Early-exercise stock options

  • 12 weeks fully paid parental leave (US)

As published by Blacksmith. Applications are handled on their site.

Skills this posting mentions

CockroachDBDistributed SystemsAdvertising

About Blacksmith

Blacksmith is the CI cloud.

All 21 openings at Blacksmith

One click, then it is written

Apply to Blacksmith with a resume written for this role.

Queue Senior Systems Engineer and I read the posting, rewrite your resume against it, draft the cover letter, and score the fit. Then you press send, or press one button and I fill in Blacksmith’s form for you.

  1. 01Drop your resume

    A PDF or a LinkedIn URL. About a minute, once.

  2. 02I rank the openings

    Every weekday morning, the live catalog scored against your history. Up to 20 worth your time, not two hundred links.

  3. 03Each one is written up

    Resume rewritten for the posting, a cover letter, a fit score. Press send, or let me fill in the form.

  • 25 sent a week, free
  • No card
  • Nothing sent until you say so

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Put this to work

Paste your career in once. Every application after that is written for you.

Drop a resume or a LinkedIn URL. I rank the live openings against it, rewrite the resume and write a cover letter for the best of them, and fill in the employer's form when you press the button. You read, you decide what goes out.

  1. 01Drop your resume

    A PDF or a LinkedIn URL. About a minute, once.

  2. 02I rank the openings

    Every weekday morning, the live catalog scored against your history. Up to 20 worth your time, not two hundred links.

  3. 03Each one is written up

    Resume rewritten for the posting, a cover letter, a fit score. Press send, or let me fill in the form.

  • New matches ranked and written before you are up.
  • Every bullet stays inside what your history supports. Nothing invented.
  • Queued, submitted, interviewing, offer: one screen, not a spreadsheet.

Free, no card. Up to 25 applications sent a week, and nothing is sent until you say so.

Listed from the job board Blacksmith publishes. Refolk is not the employer and does not handle their hiring. Applications go to Blacksmith directly.

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