ML systems engineering · GPU inference · efficient training
I build and profile model runtimes, training pipelines, and evaluation infrastructure. My work connects a concrete bottleneck or correctness failure to a small implementation, reproducible evidence, and upstream review.
Portfolio · Upstream contributions · Project index · Contribution workspaces
| Project | Contribution | Evidence |
|---|---|---|
| vLLM | Generate output logprobs now carry integer token IDs directly instead of "token_id:N" placeholder strings, with aligned Python/Rust frontend behavior, rank preservation, derender compatibility, tests, and documentation. |
Merged #58181 |
| PyTorch TorchTitan | Vocabulary-sharded RL policy statistics: avoid full-vocabulary gathers while preserving logprob/gradient semantics and the batch-invariant fallback. | Merged #4685 |
| Apache DataFusion | Authored: make sliced list set operations process the visible range rather than hidden backing data; one documented component case improved from 184.46 µs to 0.823 µs (not a whole-query speedup). Reviewed: merged Parquet RLE/dictionary-read PR #24227; benchmark analysis identified up to ~9× regressions on high-cardinality GROUP BY workloads, and the findings were cited by the PR author in follow-up performance discussion. |
Merged #25300 · Reviewed, merged #24227 |
| Apache Arrow-rs | Harden temporal casts against overflow: respect safe/unsafe cast semantics for narrowing Time64, use checked precision increases, and add regression coverage for remaining temporal conversion paths. |
Merged #10907 |
| Triton | Incomplete-cache recovery, removal of unnecessary single-config autotuning, and tensor-indexing correctness. | Merged #10411, #10413, #10429 |
| Inspect AI | Bounded continuation of oversized sandbox JSON-RPC responses, with transport validation and cleanup. | Merged #4371 |
| GPU attention runtimes | CuTe SM120/SM121 compile-time handling in FlashAttention; per-kernel large-head shared-memory initialization in ONNX Runtime. | Merged FlashAttention #2671, ONNX Runtime #29140 |
Also: the SWE-bench skipped-test grading fix was adopted through
upstream commit a5ecda6.
PR #598 is closed, not marked merged.
The full record keeps authored PRs, adopted changes, reviews, and reports separate.
| Project | What to inspect |
|---|---|
| Single-GPU Inference Lab | Request-level prefill cost geometry, full-engine profiling, and measured serving changes. Raw artifacts, cross-hardware controls, and negative results accompany the claims. Start with the report. |
| L20 Pretraining Lab | A released 1.100B language model trained from scratch on 20.0B prediction tokens on one L20, with frozen evaluation records. Multimodal work is a separate research track, not a promoted all-purpose release. Language model card. |
| L20-CodeForge | Executable-code evaluation and verifier-guided inference, with full-suite artifacts, public/hidden-test separation, and a separate model-weight retention audit. Reproduction guide. |
vLLM sampled-token logprob transport — #57442 recovers measured L20 serving throughput from 0.67× to 0.95–0.96× of the no-logprobs baseline on the documented Qwen2.5-0.5B workloads. Open, not merged. More open work and its validation boundaries.
Python · C++/CUDA · Rust · Triton · PyTorch · vLLM