One spec, five lanes, three languages
Most test generators speak one language. Real features don't. Here's how TFactory fans a single handoff across pytest, Jest, and Playwright.
Here’s a thing nobody tells you about “AI writes your tests”: most tools only write one kind of test, in one language. Great, if your entire product is a single Python module. Less great if your feature is — like every real feature — a React form talking to an httpx endpoint backed by a database.
A monorepo team tries that single-language tool, watches it ignore 80% of the change, and politely closes the tab.
The five-lane spine
TFactory’s v0.2 plans a feature across five lanes:
unit · browser · api · integration · mutation
The Planner reads your acceptance criteria and the diff, then tags each sub-task with the lane and language it belongs in. A login feature might fan out to a pytest unit test for the token logic, a Jest test for the React hook, a Playwright browser test for the actual click-through, and an api test that hits the running endpoint. One handoff, one plan, four lanes lit.
Why lanes instead of “just write tests”
Because the lanes don’t just describe what to test — they decide how to run and judge it. A browser test gets a Playwright sandbox and is scored without expecting line coverage (you’re testing a flow, not a function). A unit test gets pytest + coverage + the full mutation probe. The verdict pipeline applies the right rubric per lane, then reports them uniformly — same five-signal card whether the test is Python or TypeScript.
That uniformity is the quiet superpower. You don’t get five different dashboards in five different dialects. You get one triage report: here are the good tests across your whole stack, ranked, with a verdict each.
Security is deliberately not a lane
We cut SAST/DAST/fuzz on purpose. They’re real, but they’re a different job with mature dedicated tools — bolting them on would have made TFactory worse at the thing it’s actually good at. Honest scope beats a longer feature list.
What it feels like
You finish a polyglot feature, hand the branch over, and watch the portal’s lane grid light up one cell at a time as the plan fans out — then collapse back into a single ranked list of tests worth keeping.
The demos include a polyglot run if you want to see the fan-out for real; the architecture page has the lane-by-lane detail.