Skip to content
CV Rocket
Get started
How it worksThe enginePricingBlogContactSign in

Open nowPosted 220 days ago

Research Engineer - AI Performance & Kernel Optimization

Zyphra16 open roles

Where
San Francisco
Work mode
On site
Get the CV for this job

From $25 per CV, paid once. No subscription.

Your applicationOpen nowResearch Engineer - AI Performance & Kernel OptimizationZyphra · San Francisco

  1. YouYes, apply to this one.

  2. CV RocketCV written for this posting.

  3. 25 readersRecruiter, hiring manager, skeptic. Round after round.

  4. CV RocketApplied on Zyphra's own form.

The reply lands in your private mailbox

3×more interviews than doing it yourself with ChatGPT.

The clock on this job

Early applications get read.

11.9% of postings close within 7 days. Measured by our own scanner across the market.

Share of postings closed within
  1. 2.1%1 day
  2. 4.4%3 days
  3. 11.9%7 days
  4. 18.6%14 days
  5. 35.6%30 days
  6. 45.1%60 days
This job: posted 220 days ago

The posting

ZYPHRA IS AN ARTIFICIAL INTELLIGENCE COMPANY BASED IN SAN FRANCISCO, CALIFORNIA.

THE ROLE:

As a Research Engineer - AI Performance & Kernel Optimization, you will improve and optimize the performance of our large-scale language model training and inference stacks. You will work closely with our pretraining and inference teams to identify bottlenecks, design and implement highly optimized kernels, and push the limits of throughput, latency, and hardware utilization across a range of accelerator platforms. This role is suited for someone who enjoys deep systems work, cares about performance at every level of the stack, and is excited to translate low-level optimizations into meaningful gains for frontier-scale AI systems.

YOU’LL WORK ACROSS:

- Kernel development and optimization for large-scale ML workloads, using any level of the stack from PTX/assembly to CUDA, HIP, Triton, or other GPU DSLs

- Performance tuning for training and inference stacks across GPUs and other accelerators

- Profiling and eliminating bottlenecks in memory movement, communication, scheduling, and compute utilization

- Optimizing distributed training and inference systems for large MoE models, including large-scale model parallelism

- Portability and optimization across non-NVIDIA hardware, with special interest in AMD hardware such as the MI300x and MI355x

- Collaboration with research and infrastructure teams to turn systems improvements into real-world model training and inference gains

WHAT WE'RE LOOKING FOR / REQUIREMENTS:

- Strong engineering aptitude for building reliable, high-performance systems

- Excellent low-level performance intuition and the ability to reason about hardware-software interactions

- Are excited to rapidly learn new systems, tools, and hardware environments

- Excellent communication and collaboration skills, with the ability to work effectively across research and engineering teams

- Enjoy diving deep into the weeds and hunting down the last 10–20% of performance

QUALIFICATIONS / ADDITIONAL SKILLS:

- Experience writing highly performant GPU kernels at any level of abstraction–PTX, CUDA, HIP, Triton, or other kernel DSLs

- Experience optimizing ML workloads for large-scale training, ideally in language model pretraining or inference environments

- Experience with non-NVIDIA accelerator hardware, such as AMD, AWS Trainium, Google TPU, Qualcomm, ARM, Intel, and custom ASICs

- Strong understanding of distributed training systems and parallelism schemes, including data parallelism, tensor/model parallelism, pipeline parallelism, sharding, and communication/computation overlap

- Experience with performance engineering in other demanding parallel computing environments such as HPC, quantitative finance, scientific computing, graphics, compilers, or numerical simulation

- Strong systems intuition around memory hierarchy, bandwidth constraints, kernel fusion, launch overhead, communication overhead, and hardware utilization

- Experience using profiling and debugging tools to drive performance improvements

- Familiarity with infrastructure underlying large-scale training and inference, including collective communication libraries, and runtime performance analysis

- Background in a highly technical field such as physics, mathematics, theoretical computer science, computer science, or electrical engineering

- Any HPC experience is a strong plus

WHY WORK AT ZYPHRA:

- Our research methodology is grounded in methodical, step-by-step approaches to ambitious goals. Both deep research and engineering excellence are equally valued

- We strongly value new and crazy ideas and are very willing to bet big on new ideas

- We move as quickly as we can; we aim to minimize the bar to impact as low as possible

- We all enjoy what we do and love discussing AI

BENEFITS AND PERKS:

- Comprehensive medical, dental, vision, and FSA plans

- Competitive compensation and 401(k) plan

- Relocation and immigration support on a case-by-case basis

- In-office snacks and meals provided

- Unlimited PTO and company holidays

- In-person team in San Francisco with a collaborative, high-energy environment

From $25, paid onceGet the CV for this job

What happens when you press

One press. We do the rest.

  1. A CV for this posting

    Written against Zyphra's own wording, from every piece of relevant proof in your profile.

  2. 25 readers review it

    Recruiter, hiring manager, skeptic and more read every draft, round after round. You get the best round.

    The review screen in CV Rocket: how each CV was read, round by round.

  3. We apply on Zyphra's form

    Our application engine gets through the hardest forms there are. Where a question needs you, AI suggests the best answer. Don't want us applying from our IP addresses? Use our Chrome extension: we apply straight from your own browser.

    An application in CV Rocket: every answer filled in on the employer's form.

  4. Every reply, sorted

    Zyphra's answer lands in your private mailbox, and we classify it on arrival: interview, question, rejection.

    The CV Rocket inbox: each employer reply classified as an interview, an action or a rejection.

  5. Reply with AI

    AI helps you write the email, checks it and sends it. We show you whether the recruiter read it.

  6. The interview in your calendar

    Full integration with your calendar. The invitation goes straight in.

    An interview invitation in the CV Rocket inbox, added to the candidate's calendar.
Get the CV for this job

From $25 per CV, paid once. No subscription.

Why it works

3×

more interviews than doing it yourself with ChatGPT.

ChatGPT writes a CV and never learns what happened to it. We see every reply. For each CV we know:

  • How it was written, and how the review scored it
  • When we applied, and how long after the posting went up
  • Which posting, which company, which city
  • Who got the interview, and who heard nothing

That is how we know which CVs get called.

Get the CV for this job

From $25 per CV, paid once. No subscription.

The numbers game

More applications. More interviews.

Every application goes out with its own CV, written for that posting and paid once. Send enough of them and the law of large numbers finds you the job.

Get the CV for this job
By hand5–10
With CV Rocket100
applications a day

Nearby

Live postings like this one

Same employer first, then the same role elsewhere.

Before you press

Straight answers

Get the CV for this job

From $25 per CV, paid once. No subscription.

What if my background isn't good enough?

We make the most of the background you have. The CV uses every piece of relevant proof your profile holds, and one of the 25 readers reads your whole profile and flags what the CV left out.

Do you really apply for me?

Yes, on the employer's own form, the hardest ones included. Where a question needs you, you answer it right there and AI suggests the best answer. Don't want us applying from our IP addresses? Use our Chrome extension: we apply straight from your own browser.

Is it a subscription?

No. You pay once per CV, from $25. Every application goes out with its own CV, written for that posting.

One job. One CV.
Paid once.

Pick the posting you want. We write for it, apply for you and catch the reply.

Get the CV for this job

From $25 per CV, paid once. No subscription.