jobctl

Software Engineer - Kernels/CUDA (C++)

SpaceXSI - Palo Alto, CA, Seattle, WA - original posting ->
Status
Open
Remote policy
Not stated
Employment type
Not stated
Salary
Not stated
Categories
Infrastructure
Tech
cppsoftware
Source
xai
First observed
2026-08-18 21:02 UTC
Last seen
2026-10-13 05:08 UTC
Source claims posted
2026-03-06 23:27 UTC
Consecutive misses
0 of 3

What the posting says

SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where we are not. Today, SpaceX is actively developing the technologies to make this possible, with the ultimate goal of making life multiplanetary and expanding consciousness to the stars.

SpaceXSI is building Super Intelligence to understand the universe and help expand humanity’s knowledge and capabilities. We work across the full Super Intelligence stack: compute (Colossus supercomputers), models (Grok), and applications (Grok Bot, Grok Build, Grok Imagine, Grok Voice, and X). We're creating a powerful flywheel where more compute trains better models, better models power more useful products, and what we learn from people using those products shapes what we build next.

ABOUT THE ROLE:

We are building one of the world’s largest AI supercomputers from the ground up. As part of the Compute Infrastructure team, you will own both the raw GPU supercomputer and the platform layer that runs on top of it. You will work across the full stack — from low-level GPU kernel optimizations and Linux kernel internals to massive-scale orchestration and virtualization — to make training and inference at SpaceXSI as fast, reliable, and scalable as possible.

This is a broad, high-impact role that combines hardcore supercompute and compute infrastructure work. Your contributions will directly accelerate Grok’s training speed and overall AI progress.

RESPONSIBILITIES:

Design, build, and optimize massive GPU clusters for extreme-scale training and inference workloads

Develop and tune low-level CUDA kernels (GeMM, Attention, etc.), using CUTLASS, Tensor Cores, and Nsight for maximum performance

Profile, debug, and eliminate bottlenecks across GPU memory hierarchy, networking fabric, filesystems, and multi-GPU operation

Collaborate closely with AI research teams to deliver production-grade performance and scalability

PREFERRED SKILLS AND EXPERIENCE:

Deep low-level systems programming (C/C++/PTX/SASS)

Strong experience with large-scale GPU clusters or distributed compute infrastructure at production scale

Hands-on work with GPU kernel optimization (CUTLASS, custom kernels, Nsight profiling)

Track record of building or running high-performance infrastructure for AI workloads (training or inference platforms)

Ability to reason from first principles and optimize for both memory-bound and compute-bound scenarios

COMPENSATION AND BENEFITS:

$180,000 - $440,000 USD

Base salary is just one part of our total rewards package at SpaceXSI, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks.

SpaceXSI is an equal opportunity employer. For details on data processing, view our Recruitment Privacy Notice.

Quality

Completeness: 45%
Honesty: 100%

Based on 18 observation(s).

Timeline

  1. *
    #161888 2026-08-18 21:02 UTC
    Published
  2. ~
    #167614 2026-08-19 01:02 UTC
    Modified
    • source_updated_at
      2026-08-18T15:14:36-04:00->2026-08-18T18:10:46-04:00
  3. ~
    #199838 2026-08-20 01:16 UTC
    Modified
    • source_updated_at
      2026-08-18T18:10:46-04:00->2026-08-19T18:53:03-04:00
  4. ~
    #231283 2026-08-21 04:27 UTC
    Modified
    • source_updated_at
      2026-08-19T18:53:03-04:00->2026-08-20T20:36:54-04:00
  5. ~
    #259245 2026-08-21 23:53 UTC
    Modified
    • source_updated_at
      2026-08-20T20:36:54-04:00->2026-08-21T18:24:01-04:00
  6. ~
    #388556 2026-08-26 22:37 UTC
    Modified
    • source_updated_at
      2026-08-21T18:24:01-04:00->2026-08-26T17:48:54-04:00
  7. ~
    #394184 2026-08-27 06:39 UTC
    Modified
    • source_updated_at
      2026-08-26T17:48:54-04:00->2026-08-26T23:12:24-04:00
  8. ~
    #407429 2026-08-27 22:40 UTC
    Modified
    • source_updated_at
      2026-08-26T23:12:24-04:00->2026-08-27T18:09:48-04:00
  9. ~
    #557763 2026-09-03 21:32 UTC
    Modified
    • Locations
      Palo Alto, California->Palo Alto, CA
    • source_updated_at
      2026-08-27T18:09:48-04:00->2026-09-03T14:58:20-04:00
  10. ~
    #564517 2026-09-04 05:32 UTC
    Modified
    • source_updated_at
      2026-09-03T14:58:20-04:00->2026-09-04T00:53:32-04:00
  11. ~
    #646332 2026-09-08 23:51 UTC
    Modified
    • source_updated_at
      2026-09-04T00:53:32-04:00->2026-09-08T18:33:02-04:00
  12. ~
    #963241 2026-09-24 06:03 UTC
    Modified
    • source_updated_at
      2026-09-08T18:33:02-04:00->2026-09-23T23:22:06-04:00
  13. ~
    #974986 2026-09-24 18:07 UTC
    Modified
    • source_updated_at
      2026-09-23T23:22:06-04:00->2026-09-24T13:08:39-04:00
  14. ~
    #1100267 2026-09-30 22:44 UTC
    Modified
    • source_updated_at
      2026-09-24T13:08:39-04:00->2026-09-30T16:41:12-04:00
  15. ~
    #1189388 2026-10-05 18:50 UTC
    Modified
    • Locations
      Palo Alto, CA->Palo Alto, CA, Seattle, WA
    • source_updated_at
      2026-09-30T16:41:12-04:00->2026-10-05T11:29:25-04:00
  16. ~
    #1295319 2026-10-12 13:22 UTC
    Modified
    • Description
      SpaceXAI’s mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our...->SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where...
  17. ~
    #1311392 2026-10-13 01:08 UTC
    Modified
    • Description
      SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where...->SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where...
    • source_updated_at
      2026-10-05T11:29:25-04:00->2026-10-12T19:35:19-04:00
  18. ~
    #1314366 2026-10-13 05:08 UTC
    Modified
    • Organisation
      SpaceXAI->SpaceXSI