fluentui — Engineering Performance
22 engineers all time · Jan 2025 – Sep 2026 · built 2026-09-30 · GitHub
Performance snapshot
Today's rolling 90-day reading for fluentui, compared with the start of the series. Pick a window to move that comparison point.
Avg. perf / dev / mo
+167.1%
0.52 → 1.39 ETV
Active engineers
−52.4%
21.0 → 10.0
Features
−5.5pp
36.7% → 31.2%
vs. Microsoft
0.21x
0.39x → 0.21x · −79% below
fluentui vs. Microsoft
Per-engineer ETV for fluentui against Microsoft as a whole. Both lines are 90-day rolling averages scaled to a 30-day month, so they share one axis and can be read against each other at any point. Pick a window to zoom the chart to it.
Performance Composition
Each month's output split by type of work: Features (new value), Maintenance (sustaining systems), Tests, Docs, and Fixes (rework). The yellow line is output per engineer, so when it rises each engineer is delivering more, whatever the team size did. Unit: Engineering Throughput Value (ETV).
Engineering capacity
Effective engineers behind fluentui, against its pre-AI baseline. Each subject has its own: fluentui's is 0.52 ETV / dev / mo, its first reading in Q1 2025. Per-engineer ETV divided by that gives a capacity multiple, and that multiple applied to the engineers active in the trailing 90 days turns it into engineer-equivalents. The line is the real headcount, so the gap between line and area is what the leverage is worth. Because each baseline is its own, every subject opens at 1.0x on its first day: multiples measure improvement and are not comparable between subjects.
Knowledge concentration
How dependent is this repo on a small number of engineers? Higher top-1 share = higher key-person risk.
Dmytro Kirpa owns 16.6 % of commits.
Behind the numbers
Written summary of the work completed each month.
No monthly reports available yet.
Top engineers
Most impactful commits
Top 10 by ETV in the all-time window.
- 12.8ETVfeat(web-components): generate SSR templates and stylesheets into src/ (#36259) ## Previous Behavior SSR template HTML and stylesheet CSS were generated at build time and written only to `dist/`. The output had no presence in `src/`, was never committed, and contributors had no way to inspect the DSD output without running a build. ## New Behavior SSR templates and stylesheets are now generated next to their `*.template.ts` / `*.styles.ts` siblings in `src/` and committed to the repo. This makes the DSD output visible during the WC v3 alpha. `yarn compile` no longer regenerates them; it copies `src/**/*.template.html` and `src/**/*.styles.css` into `dist/esm/`. `yarn generate:ssr` runs the harness's `generateFTemplates` and `generateStylesheets` with `outDir: 'src'` and formats the result with Prettier. `yarn check:ssr` runs the generators against a staging directory and compares the result to `src/` and the working tree. It reports `unchanged`, `created`, `updated`, `stale`, `handEdited`, and `conflicts`, and exits non-zero when stale, hand-edited, or conflicting files appear. `yarn compile` is extended to copy `src/**/*.template.html` and `src/**/*.styles.css` into `dist/esm/` after `tsc`, preserving subdirectory structure. The old `build:ssr`, `build:ssr:styles`, and `build:ssr:templates` scripts were removed.John Kreitlow · 3fc293f0 · 2026-06-11
- 4.7ETVtest(react-menu): add hook-level regression tests for react-menu components (#36080)Victor Genaev · cb0574cc · 2026-05-15
- 4.4ETVfeat(cli): initial implementation of FluentUI CLI (#36734) Co-authored-by: Dmytro Kirpa <dmytrokirpa@microsoft.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>Martin Hochel · b3b5a9ce · 2026-09-16
- 3.4ETVfix(web-components): harden component lifecycle for SSR/DSD hydration scenarios (#35838)John Kreitlow · da4bf9e4 · 2026-04-06
- 2.8ETVfix(react-components,react-charts): migrate to R19 compatible JSX.* namespace types (#34923)Martin Hochel · bbaeb73e · 2025-07-31
- 2.5ETVfix(react-components): make v9 source compatible with React 19 types and run integration type-check against source (#34864)Dmytro Kirpa · cf1eb5f9 · 2025-09-04
- 2.4ETVfeat(react-toast): headless toast implementation (#36059) Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>Dmytro Kirpa · da3b7a4f · 2026-05-28
- 2.3ETVfeat(web-components): add Dropdown, Listbox, and Option components (#32116)John Kreitlow · f706fe1a · 2025-02-03
- 2.3ETVfeat(react-headless-components-preview): add Tag family (#36230)Victor Genaev · ecb629c1 · 2026-05-27
- 2.2ETVfeat(react-headless-components-preview): add Popover & positioning (#36006)Victor Genaev · d44cd64b · 2026-05-01