# Remove test combinations nobody acts on

A test grid that grew for years, cut back to the combinations somebody would actually act on.

Category: Pipeline speed and cost
Source: https://letsship.ai/use-cases/prune-matrix-combinations
Published: 2026-08-25

## Goal

Reduce a pipeline matrix to the combinations that are actually acted on.

## Acceptance criteria

- Each removed combination is justified in writing
- The remaining set still covers the supported platforms
- Minutes saved are recorded
- The supported-platform list is confirmed with whoever owns it

## What lands as proof

A written coverage argument for what remains, so the reduction is a decision rather than an omission.

## Prompt

Copy this to an agent to open the ticket:

```text
Create a Linear issue in my team and assign it to the SHIP agent.

Title: Prune the {workflow} test matrix

Description: Reduce a pipeline matrix to the combinations that are actually acted on.

Acceptance criteria:
- Each removed combination is justified in writing
- The remaining set still covers the supported platforms
- Minutes saved are recorded
- The supported-platform list is confirmed with whoever owns it

Before you create the issue, list this repository's matrix combinations and how often each has caught a unique failure. Replace {workflow}.
```

## Questions

### What does the agent actually change?

The ticket is scoped to one outcome: reduce a pipeline matrix to the combinations that are actually acted on. Work that serves that outcome is in scope, and anything outside it is left for a separate ticket, so the pull request stays reviewable.

### How do I know the work is done?

The pull request carries the evidence, not only the diff. Here that means the coverage argument written down alongside the removal, so a reviewer can confirm the result without reproducing the work locally.

### How much oversight does this need?

The run stops for the plan, and the review bar is raised afterwards so that smaller suggestions block the merge too, not only serious findings.