jeff is a self-hosted drop-in replacement for TypeSafe's jev System One API, powered by the 400M-parameter GLiFormer-large-v1 model. It serves `choice`, `score`, and `noul` classification questions over a compatible wire format, so existing applications using the official `typesafe-sdk` can point at it by changing a single base URL. Deployment targets include GPU (L4, A10G) and CPU (ONNX Runtime with int8 quantization) via Modal, with ~50 req/s per container throughput on L4. Benchmarks on 1,600 labeled items show it costs roughly a quarter of jev per million requests but trails significantly on reasoning-heavy tasks like irony and reading comprehension.
- `JEFF_ISOLATE=nouls` (default) gives separate encoder passes per noul question to reduce cross-question interference; choice and score questions share a pass unless set to `all`
- Default temperature of 3.2 calibrates noul probabilities; setting it to 1 makes `score` output match the weighted average of displayed probabilities
- A smaller `gliformer-base-v1` variant with `JEFF_NOUL_MODE=single` is recommended for faster local iteration