One test suite, six task runners, the same 984 cases

Each case is a small workspace and the outcome a user would see. All six tools run the same 984 cases, each in a sandbox.

xychart-beta
  title "Cases passed, of 984"
  x-axis [vx, Nx, Turborepo, moon, "Vite Task", Nix]
  y-axis "cases" 0 --> 984
  bar [982, 640, 627, 579, 499, 473]

vx 747b26f · Turborepo 2.11.10 · Nx 24.0.2 · Vite Task 1.4.0 · moon 2.6.5 · Nix 2.34.6 · 2026-11-07 · every case

The cases come from every tool’s own tests

The cases are compiled from the test suites of Nx, Turborepo, Vite Task, moon, Nix and vx. A case names no tool’s config. It says which projects exist, what each task runs, and what must hold afterwards.

flowchart LR
  W[small workspace] --> S[steps: edit, commit, run]
  S --> A1[which commands ran]
  S --> A2[files left on disk]
  S --> A3[exit code]
  S --> A4[what the tool reports]

A thin adapter turns the case into each tool’s own config. The harness marks each command as it starts and ends, so “ran” means it ran.

Where the scores split

Group	Cases	vx	Nx	Turborepo	moon	Vite Task	Nix
graph	149	149	113	91	84	86	57
inputs	302	302	186	187	192	177	175
outputs	223	223	156	160	122	139	158
affected	97	97	57	68	69	0	0
watch	31	31	27	28	0	0	0
sandbox	18	18	0	1	0	1	15

A case a tool cannot express counts as not passed. Its users cannot get that behaviour either.

Each case says why it matters

Args forwarded to a server reach it as typed, never expanded by a shell
vx        pass
moon      pass
Nx        fail  seen.txt is "<0><0>…", expected "<$(id -u)><`id -u`>…"

Every case carries three or four sentences on what goes wrong without it. Here a second shell ran $(id -u), a command nobody typed.

vx misses 2 cases. Both need programs a dependency puts on PATH, which vx left to the tools you already have.

All cases, filters and each tool’s detail: Conformance. More at vznjs.github.io/vx.