Fast and Reliable Testing

Run fewer tests. Trust every result.

Harness combines Test Intelligence, automatic flaky test quarantine, and enforced code coverage — so your pipeline runs faster without losing signal or trust.

Start for FreeRead the docs
80%
reduction in tests run
avg. across customers
faster build times
with full optimization
0
false positives
ML tracks all test deps
5+
supported languages
Java, Python, Ruby, .NET, Go
Three pillars of reliable testing

Every safeguard runs automatically on every build

Most test suites make you choose between speed and trust. Test Intelligence, flaky test quarantine, and coverage enforcement run together on every build, so the gains compound instead of trading off.

Test Intelligence

Only run the tests your change actually touches

Test Intelligence maps every test to the code it exercises, so when a PR lands, your pipeline runs the tests that matter and skips the rest — safely.

Intelligent test selection. Harness analyzes each code change and automatically runs only the unit tests that exercise it, skipping the rest without sacrificing signal.

Multi-language support. Works out of the box with Java, Python, Ruby, C#, Scala, Kotlin, and JavaScript (beta), across frameworks like JUnit, pytest, RSpec, and Maven.

Parallel test execution. Splits the remaining tests into parallel workloads that run simultaneously, compounding the time saved from smart selection.

See Test Intelligence docs

Language and framework support

Test Intelligence works with the languages and frameworks your team already uses.

Java

JUnit 4 & 5, TestNG

Python

pytest, unittest

Ruby

RSpec, Minitest

.NET / C#

NUnit, MSTest, xUnit

Go

Go test

JavaScript

Jest, Mocha (coming soon)

Kotlin

JUnit via JVM

Scala

ScalaTest via JVM

Flaky Test Detection and Quarantine

Stop chasing tests that lie

Tests that pass and fail inconsistently erode trust in your pipeline and waste hours on reruns. Harness automatically identifies flaky tests and quarantines them, so a flaky failure never blocks a good deploy.

Automatic detection

Harness tracks pass/fail history for every test across builds and flags tests with inconsistent outcomes — no manual tagging required.

Quarantine, not deletion

Flaky tests are moved out of the main pipeline gate automatically. They keep running and reporting, but they can no longer block a merge.

Root cause visibility

See flake rate, failure history, and last known-good run for every quarantined test, so your team can fix the underlying issue instead of ignoring it.

See test management docs

Flaky tests · Last 30 days

AuthServiceTest.testConcurrentLogin38%
19 of 50 runsQuarantined
SearchIndexTest.testRebuild27%
13 of 48 runsFlagged
CacheTest.testExpiry15%
7 of 46 runsMonitoring
3 tests quarantined this month — 0 blocked merges from flaky failures
Code Coverage

Know exactly what your tests protect

Test Intelligence tracks coverage alongside test selection, so reducing what you run never means losing visibility into what's protected.

Repository and branch coverage

Track coverage at both the repository and branch level, with trend lines so you can see whether coverage is improving or slipping over time.

File-level breakdown

Drill into any file to see exactly which lines are missed, so teams can prioritize coverage work where it matters most.

Enforced in the pipeline

Set coverage thresholds as a pipeline gate. Builds that drop below the bar fail fast, before the gap reaches production.

See test management docs
Get started

Cut your test suite time by 80%

Test Intelligence takes minutes to configure and starts delivering results on the first build. No test refactoring required.

Start for Free Read the docs