Compare Product States

eve can answer two product-history questions that Git diffs do not try to answer:

What changed in the product since a previous snapshot?
What changed between two recorded product states?

Use changelogs when you need release-note style output. Use comparison when you need to inspect the product delta between two snapshots.

Generate a changelog

eve changelog groups snapshots into product-facing release notes.

eve changelog
eve changelog --since <snapshot-id>
eve changelog --since 2026-07-01
eve changelog --from <from-snapshot-id> --to <to-snapshot-id>
eve changelog --markdown

--since <snapshot-id> starts after the boundary snapshot. Date ranges include snapshots created on or after the provided UTC date.

Use --markdown when drafting release notes for a GitHub release, changelog entry, or pull request.

Compare snapshots from the CLI

eve compare compares two snapshots from the same repository.

eve compare <from-snapshot-id> <to-snapshot-id>
eve compare <from-snapshot-id> <to-snapshot-id> --markdown

The comparison output groups product history into:

added, changed, and fixed behavior
decisions
risks
validation
timeline entries

The comparison is product-level. It complements Git diffs; it does not replace them.

Compare in the local UI

Start the local runtime:

eve

Open a repository page and choose the Compare tab.

The Compare tab lets you:

choose Earlier and Later endpoints
search snapshots by title, type, date, or id
use quick ranges such as Latest pair, Last 3, Last 5, and All
review selected snapshots in chronological order
scan a compact comparison board for changes, evidence, validation, decisions, risks, and timeline entries

eve keeps the final range in chronological order, so selecting endpoints in the wrong order does not produce a reversed comparison.

API support

The local runtime exposes the same comparison model at:

GET /api/compare?from=<snapshot-id>&to=<snapshot-id>

Both snapshots must belong to the same repository. The response is designed for the local UI and includes the selected range plus grouped product-history sections.

When to use it

Use comparison when reviewing a release span, checking what changed since a stable snapshot, or helping an agent understand the product delta before making another change.