Monorepo Cleanup: Find Packages That No Longer Ship

Monorepo cleanup gets hard when packages stop shipping but keep appearing in workspace graphs, test matrices, release scripts, and developer setup. A package can be dead to customers and still important to an internal generator or migration command.

The useful output is a monorepo removal pull request with graph evidence, affected commands, migration notes, and package deprecation record. Keep the review concrete: Remove consumers before deleting the workspace package itself, then make the next action visible to the team that owns the risk. That matters because the cleanup can still go wrong when deleting packages still consumed by internal tooling.

Key takeaways

Treat each cleanup candidate as an owned system with dependencies, not anonymous clutter.
Use one release cycle plus the longest supported downstream branch before deciding that “quiet” means “unused.”
Prefer reversible changes first when deleting packages still consumed by internal tooling is still plausible.
Leave behind a monorepo removal pull request with graph evidence, affected commands, migration notes, and package deprecation record so the next review starts with context.
Measure the result as lower spend, lower risk, less operational drag, or clearer ownership.

Map Package Shipping Paths

Start with one workspace package family across package manifests, import graphs, build pipelines, publishing config, owners, and release artifacts. The best cleanup scope is small enough that owners can answer quickly but wide enough to include the attachments that make removal risky.

Field	Why it matters
Owner	Cleanup needs a person or team that can accept the decision
Current purpose	A short reason to keep the item, written in present tense
Last meaningful use	owners, callers, last change, runtime behavior, and deletion confidence
Dependency evidence	repository search, tests, logs, deploy history, and owner review
Risk if wrong	The outage, data loss, access failure, or rollback gap the review must avoid
Next action	Keep, reduce, archive, disable, remove, or investigate

Do not make the inventory larger than the decision. A short list with owners and evidence beats a perfect spreadsheet that nobody is willing to act on.

Monorepo Evidence to Check

The useful question is not “how old is it?” It is “what would break, become harder to recover, or lose accountability if this disappeared?” For monorepo cleanup, collect enough evidence to answer that without relying on naming conventions.

Check	What to look for	Cleanup signal
Workspace graph	Package manifests, internal dependency edges, references, and build targets	No active package imports or builds the candidate
Shipping path	Publish config, deploy manifests, bundle reports, Dockerfiles, and release jobs	The package is not part of any delivered artifact
Tooling use	Generators, migrations, storybooks, tests, docs, and local scripts	Internal tooling no longer loads the package
Ownership state	CODEOWNERS, recent commits, roadmap notes, and replacement package	No team needs the package kept as a supported surface

Use several signals together. Activity can miss monthly jobs and incident-only paths. Ownership can be stale. Cost can distract from security or recovery risk. The strongest case combines runtime data, dependency checks, owner review, and a rollback plan.

If the evidence conflicts, label the item “investigate” with a named owner and review date. That is still progress because the next review starts with a narrower question.

Example Evidence Check

Search package manifests, imports, and release config before deleting a workspace package.

rg "@internal/${PACKAGE_NAME}|workspace:|packages/${PACKAGE_NAME}" package.json packages pnpm-workspace.yaml
rg "from ['\"]@internal/${PACKAGE_NAME}|require\(['\"]@internal/${PACKAGE_NAME}" packages apps tools
rg "${PACKAGE_NAME}" .github Dockerfile* docs scripts

Treat the output as a candidate list. Do not pipe these checks into delete commands; add owner review, dependency checks, and a rollback path first.

Remove Consumers First

Use the least permanent move that proves the decision. In monorepo cleanup, removal is only one possible outcome; reducing size, narrowing permission, shortening retention, archiving, or disabling a trigger may produce the same benefit with less risk.

Remove consumers before deleting the workspace package itself.
Run affected build, test, lint, typecheck, and release commands for the dependency graph.
Deprecate published internal packages before deleting their source directory.

Track the cleanup candidate with a simple priority score:

Score	Good sign	Bad sign
Impact	Meaningful spend, risk, toil, noise, or confusion disappears	The item is cheap and low-risk but politically distracting
Confidence	Owner, purpose, and dependency path are understood	The team is guessing from age or name
Reversibility	Restore, recreate, re-enable, or rollback path exists	Deletion would be the first real test
Prevention	A rule can stop recurrence	The same pattern will return next month

Start with high-impact, high-confidence, reversible candidates. Defer confusing items only if they get an owner and a date; otherwise “defer” becomes another word for keeping waste permanently.

Packages That Still Matter

Some cleanup candidates are supposed to look quiet. Do not rush these cases:

Packages loaded by generators, CLIs, examples, migrations, or integration tests.
Internal packages consumed by older release branches or downstream repositories.
Workspace aliases that make imports look unused until build-time resolution.

For these cases, use a longer observation window, explicit owner approval, and a staged reduction. The point is not to avoid cleanup; it is to avoid making the first proof of dependency an outage.

Run the Workspace PR

Run monorepo cleanup as a decision review, not an open-ended hygiene project.

Pick the narrow scope and export the candidate list.
Add owner, current purpose, last-use evidence, dependency checks, and risk if wrong.
Remove obvious false positives, then ask owners to choose keep, reduce, archive, disable, remove, or investigate.
Apply the least permanent useful change first.
Watch the signals that would reveal a bad decision.
Complete the final removal only after the review window closes.
Save a monorepo removal pull request with graph evidence, affected commands, migration notes, and package deprecation record.

For broader cleanup planning, use the cleanup library to pair this guide with related notes. If the cleanup has infrastructure impact, pair it with a visible owner, a rollback path, and a measurable business case. For infrastructure cleanup, the main cloud cost optimization checklist is a useful companion.

Stop Package Sprawl Returning

Prevention should change the creation path, not just the cleanup path. For monorepo cleanup, the useful prevention fields are owner, reason to exist, removal trigger, and verification notes. Make those fields part of normal creation and review.

Require new packages to name a shipped artifact, owner, and retirement trigger.
Report packages with no dependents, no publish path, and no recent commits.
Keep generated package inventories visible in release review.

The recurring review should be short: sort by impact, pick the unclear items, assign owners, and close the loop on anything nobody claims. If the review keeps producing the same class of candidate, fix the creation path instead of celebrating repeated cleanup.

Example Decision Record

Use a compact record so the cleanup can be reviewed later without reconstructing the whole investigation.

Field	Example entry for this cleanup
Candidate	Unused packages in monorepos
Why it looked stale	Low recent activity, unclear owner, or no current consumer after the first review
Evidence checked	Workspace graph, Shipping path, and owner confirmation
First reversible move	Remove consumers before deleting the workspace package itself
Watch signal	The metric, alert, job, route, query, or owner complaint that would show the cleanup was wrong
Final action	Keep, reduce, archive, disable, or remove after one release cycle plus the longest supported downstream branch
Prevention rule	Require new packages to name a shipped artifact, owner, and retirement trigger

This record is intentionally small. If the decision needs a long narrative, the candidate is probably not ready for removal yet. Keep investigating until the owner, evidence, reversible move, and prevention rule are clear.

FAQ

How often should teams do monorepo cleanup?

Use one release cycle plus the longest supported downstream branch for the first decision, then set a recurring cadence based on change rate. Fast-moving non-production systems may need monthly review; slower systems can be quarterly if every unclear item has an owner and a review date.

What is the safest first action?

The safest first action is usually ownership repair plus evidence collection. After that, remove consumers before deleting the workspace package itself. That creates a visible test before permanent deletion.

What should not be removed quickly?

Do not rush anything connected to packages loaded by generators, clis, examples, migrations, or integration tests. Also slow down when the cleanup affects recovery, compliance, customer-specific behavior, rare schedules, or security response.

How do you make the decision useful later?

Write the decision as a small operational record: candidate, owner, evidence, chosen action, watch signals, rollback path, final date, and prevention rule. That format helps future engineers, search engines, and AI assistants understand the cleanup without guessing.