ML Systems Engineer, Model Architectures (Mid/Senior/Principal)

About Positron AI

Positron AI is building next-generation AI inference accelerators designed from the ground up for low-latency, high-throughput large language model inference. Chips built for the training era keep running into two walls at inference time: memory bandwidth and chip-to-chip networking. We designed our architecture to break through both. Our first-generation Atlas systems are already in production on Oracle Cloud Infrastructure. Asimov, our first custom ASIC, takes that architecture to silicon. In simulations, Asimov delivers several times more tokens per dollar and tokens per watt than leading GPUs, at a fraction of the power. Paired in our Titan system, Asimov is built to serve models beyond 16 trillion parameters. In September 2026, we raised $875 million at a $5 billion valuation. NEA led the round, joined by Atreides Management, Valor Equity Partners, and others, to bring Asimov and Titan to market. Our team includes engineers from Groq, Lambda, NVIDIA, Meta, F5, and many other industry leaders.

Role Overview

As a ML Systems Engineer, you will be the engineer who gets new model architectures running on our hardware first, in simulation, before RTL or silicon exists. You will work with chip architects, the compiler and SDK teams, and customers to understand what each new architecture demands of the hardware and to make sure our simulators can execute it bit-exactly.

The work is implementation-heavy: new attention variants, mixture-of-experts, embeddings, and quantization formats, implemented in our simulator and verified against reference frameworks. You will set the standard turnaround for bringing up a new model and drive toward making that path fully automated.

Key Responsibilities

Simulator Implementation

• Implement the operators, numerics, and memory layouts that new model architectures need in our simulator, bit-exact against a reference implementation.
• Extend simulator coverage across the full inference path, including prefill and decode, embeddings, attention variants (grouped-query, gated, linear, and sparse), mixture-of-experts routing, and quantized formats.
• Maintain reference comparisons and regression coverage so model support stays correct as the simulator and hardware evolve.

Architecture Evaluation

• Evaluate new architectures before hardware exists, identifying what they require of compute, memory, and data movement and what the chip would need to change.

Customer Model Bring-Up and Automation

• Bring customer models up in simulation ahead of emulator and hardware runs, and own the turnaround time for doing so.
• Partner with the agentic tooling engineer to automate new-model bring-up end to end, from model specification to simulator coverage.

Required Qualifications

• 4+ years of experience as an ML systems or inference engineer.
• A strong understanding of transformer internals at the operator level, including attention variants, mixture-of-experts, embeddings, KV cache, and quantization (INT8 and FP8).
• Demonstrated experience implementing or porting model inference by hand in PyTorch, llama.cpp, vLLM, TensorRT-LLM, or a custom runtime.
• Hands-on experience debugging numerical mismatches against a reference down to the operator and the bit.
• Ability to read a model architecture paper and turn it into a working, verified implementation.
• Strong Rust skills, or expert-level C/C++ skills and a willingness to work in Rust day to day, along with strong Python skills for model and reference work.
• Excellent communication skills, with the ability to explain what a new architecture needs from the hardware and where the current design falls short.

Preferred Qualifications

• Experience mapping models onto accelerator hardware or writing kernels for a non-GPU architecture.
• Prior experience serving as the technical point of contact for customer model requests.

Leveling & Scope

While this role is currently posted at a specific level, we are a growth-oriented organization and are open to hiring at a more senior level for the right candidate. Please note that this job description serves as a focused but generalized overview of the role; specific responsibilities and impact expectations will be tailored to the experience and seniority of the final hire.

Why Join Us?

• You will be the first engineer to run each new frontier model architecture on our hardware, and your findings will feed directly into how our next chips are designed.
• You will build the path toward fully automated model bring-up, working across chip architecture, compiler, SDK, and customer teams.

Compensation & Benefits

The base salary range for this role is; Mid: $160,000-$220,000, Senior: $220,000–$270,000, Principal: $270,000-$350,000.

Please note that the figures provided represent the base salary range only and do not include other elements of our total compensation package, equity, or comprehensive benefits.

At Positron AI, we value the unique expertise each candidate brings. While the range above reflects our typical expectation for the position, we reserve the flexibility to exceed this range for candidates whose specialized skills, significant experience, or unique qualifications fall outside the standard scope of the role. Final offers are determined based on a variety of factors, including internal equity, and individual impact.

Benefits & Perks

We want you to do your best work and feel confident that you and your family are taken care of. That means comprehensive coverage, real time to rest, and support for your future.

Health and wellness

• Fully company-paid medical, dental, and vision insurance for you and your dependents
• Company-paid life and disability coverage, with voluntary options to add more
• Supplemental hospital, critical illness, and accident coverage available

Time off and flexibility

• Unlimited paid time off; we encourage everyone to truly unplug and recharge
• 13 paid company holidays
• Remote-first culture with a company-provided computer and home office setup

Compensation and future

• Competitive salary and equity
• 401(k) with company matching, eligible from day one

Visa Support

This position is open to candidates currently authorized to work in the U.S. We cannot provide new visa sponsorship for this role but are open to facilitating H-1B visa transfers for eligible candidates.

Equal Opportunity Employer. If you're excited about the role but don't meet every bullet, we'd still love to hear from you.