nilsmatteson.com *** est. 2026 *** inference engineering *** inferact-sponsored vLLM fellow *** cold starts, model loading, GPU memory *** currently poking at kernel tuning *** music, guitar, running, skiing *** the marquee is HTML baby
Nils Matteson
I'm into inference engineering. I like making models faster to start and understanding where the time goes.
I've been working on vLLM through an Inferact-sponsored open-source fellowship with Simon Mo. Most of my time goes into what happens before a model serves its first request: loading weights, compiling code, tuning kernels, and deciding which of that work we can reuse.
I'm interested in GPU memory, caching, and the less obvious reasons a system is slow. I like following a problem through the stack, making a change, and checking whether it helped for the reason I thought it would.
I'm in San Jose, studying CS at Northeastern after finishing at UW-Madison. Outside of that, I make music in Ableton, play guitar, run, and ski when I can.
mail nilsmatteson@icloud.com · code github.com/matteso1 · resume.pdf
Lately I've worked on reusable engine snapshots and Python startup in vLLM. Right now I'm looking at MoE kernel tuning in FlashInfer and how to reuse preparation across compatible model servers. A few questions I keep coming back to:
| startup | what happens before the first useful response? |
| model loading | getting weights from storage into GPU memory |
| reusable state | which work can the next server safely skip? |
| kernel tuning | finding good choices without repeating the search |
| measurement | checking why a change made something faster |
Re-feeding Is Not Replaying: Measuring Replay Noise in Counterfactual Token-Credit Estimation
sole-author preprint · arXiv:2606.15621 · June 2026
I looked at whether resuming a model's saved decoder state produces the same measurements as feeding the text back in. The experiments compare both against repeated runs, separating replay differences from run-to-run noise. The writeup includes the setup, results, and cases where the distinction disappears.
The paper, experiment logs, and analysis code are public.
| Name | Type | Notes |
|---|---|---|
| work\vllm | File Folder | startup, model loading, reusable engine state |
| work\flashinfer | File Folder | MoE kernel tuning and cache reuse |
| work\sentinel | File Folder | Go log engine, LSM + Raft |
| work\madison-metro-ml | File Folder | transit ETAs and uncertainty |
| writing\echo-and-the-engineer.md | Markdown | essay: sycophancy, RLHF, the half-life of a belief |
| writing\project-gorgon.md | Markdown | speculative decoding at 0.66x of baseline, negative result |
| writing\madison-bus-eta.md | Markdown | the transit-ETA writeup |
| writing\wattbot-rag.md | Markdown | RAG benchmarks, 282 questions |
| refeed-drift.pdf | Adobe Acrobat Document | inference-state replay experiments |
| agents.txt | Text Document | facts for LLMs |
System: B.S. Data Science, UW-Madison (May 2026)
System: M.S. CS, Northeastern Silicon Valley (Sep 2026 - May 2028)
Registered to: Nils Matteson, San Jose CA
Running: vLLM open-source fellowship, sponsored by Inferact (Jul 2026 - present): cold start and reusable engine state
Interests: GPU memory, model loading, caches, and measurement
Off the clock: music, guitar, running, skiing
"Every program attempts to expand until it can read mail. Those which cannot are replaced by ones which can."
--
Zawinski's Law, 1995
(you are reading this inside exactly such a program)
.onion
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