v3.2 April 2026
Lumen
Inference, evaluation, and observability, quietly engineered.
The single audited surface for running, measuring, and shipping language model workloads. Built for engineering teams who treat AI as infrastructure, not as a marketing department.
CLAUDE-3.5-SONNET
412ms
GPT-4O-MINI
218ms
LLAMA-3.1-70B
384ms
MISTRAL-LARGE
502ms
GEMINI-1.5-PRO
326ms
DEEPSEEK-V3
287ms
As shipped — v3.2.1
The console — everything you ship, on one surface
§ 01
The Index
Four primitives. Nothing more.
We don't believe in forty-feature dashboards or AI that does your laundry. Lumen does four things — and does them with the rigor your production workloads quietly deserve.
§ 02
Specimen
A specimen of the type.
Each primitive composed and laid out as in a type specimen — numerals, ascenders, ligatures. The mark of well-set software.
01
Inference, routed.
One SDK across twenty-three providers. Caching, retries, and fallbacks arrive as defaults — not as features wired in over a long weekend.
Provider routing
23 supported
Streaming
SSE · WS
Fallbacks
automatic
Self-hosted models
vLLM · TGI
02
Evaluations, versioned.
Every regression caught before customers find it. Suites build themselves from real traces, prompts and models compared side by side.
LLM-as-judge
built-in
Custom assertions
unlimited
CI integration
GitHub · GitLab
Versioned suites
git-backed
03
Observability, auditable.
Nothing about your system is opaque, including its costs. Filter, replay, export every trace; tokens, latency attach themselves to each request.
Trace retention
90 days
SOC 2 Type II
audited
Self-hosted option
included
Data residency
EU · US · APAC
04
Datasets, annotated.
Every production trace becomes labeled data. Curate, version, and export evaluation sets without leaving the surface that captured them.
Source
production traces
Labeling
inline · API
Export formats
JSONL · CSV
Versioning
git-backed
§ 03
Testimonials
§ 04
Pricing
Honest pricing. No usage traps.
Three tiers, predictable per-seat costs, and a free tier generous enough to ship something real on. The way software pricing used to be, before everything became a metered horror story.
— Tier
— Suited for
— Per month