turborepo-caching

Overview of turborepo-caching skill

What turborepo-caching does

turborepo-caching is a practical skill for configuring Turborepo so repeated builds, tests, and lint runs are reused instead of recomputed. The real job-to-be-done is not just “turn on caching,” but to define task inputs, outputs, dependencies, and environment sensitivity well enough that local and CI runs become faster without serving stale artifacts.

Who should use this skill

This skill is best for teams working in a JavaScript or TypeScript monorepo with Turborepo and trying to:

• set up turbo.json correctly the first time
• add remote caching for CI and multiple developers
• reduce slow builds caused by cache misses
• migrate from loosely defined scripts to reproducible task pipelines

It is especially useful if you already know your repo structure but are unsure how to express it in Turborepo’s cache model.

What makes this skill worth installing

The value of the turborepo-caching skill is that it organizes the parts people usually get wrong:

• which files should be listed in outputs
• when dependsOn should use ^build or task-level sequencing
• how .env files and environment variables affect cache correctness
• why persistent tasks should not be treated like cacheable build steps
• how to reason about local versus remote caching in CI/CD

That makes it more useful than a generic “optimize my monorepo” prompt, because the skill is centered on Turborepo’s actual pipeline mechanics.

What the skill does not replace

This is not a full Turborepo reference and it does not inspect your repo automatically. You still need to provide your current turbo.json, task scripts, package layout, and build outputs. If your stack is not using Turborepo, this skill is a poor fit.

How to Use turborepo-caching skill

Install context for turborepo-caching

The upstream skill does not publish a bespoke installer inside SKILL.md, so use your normal skill installation flow for the wshobson/agents repository, then invoke the turborepo-caching skill by name in your agent environment.

If you are using a skill loader that supports GitHub sources, the repository path is:

https://github.com/wshobson/agents/tree/main/plugins/developer-essentials/skills/turborepo-caching

Read this file first

Start with:

• plugins/developer-essentials/skills/turborepo-caching/SKILL.md

This skill is self-contained. There are no supporting rules/, resources/, or helper scripts in the skill folder, so most of the usable guidance is in that single file.

What input the skill needs from you

For high-quality turborepo-caching usage, give the agent concrete repo facts, not just a goal. The minimum useful input is:

• your current turbo.json
• root package.json
• one or two representative workspace package.json files
• the build tool in each app or package, such as Next.js, Vite, tsup, or Jest
• which tasks should be cacheable
• expected output directories like dist/, build/, .next/, or coverage folders
• CI provider and whether remote caching is desired

Without that, the agent can only generate a generic template.

Turn a rough goal into a strong prompt

Weak prompt:

Help me optimize Turborepo caching.

Stronger prompt:

Use the turborepo-caching skill to review my monorepo pipeline. I have apps/web with Next.js, packages/ui with tsup, and packages/config with TypeScript build scripts. Here is my current turbo.json and package scripts. I want faster CI builds, safe remote caching, and fewer cache misses when only UI code changes. Propose a revised turbo.json, explain each outputs entry, identify env vars that should affect cache keys, and call out any tasks that should not be cached.

That prompt works better because it asks for a concrete artifact, gives the dependency graph, and defines success criteria.

Ask for these outputs specifically

The turborepo-caching skill is most useful when you request one or more of these deliverables:

• a revised turbo.json
• a task-by-task cacheability review
• an outputs audit
• an environment variable audit
• CI remote caching setup guidance
• a cache-miss debugging checklist

This avoids broad architectural answers and pushes the agent toward configuration you can apply.

Typical workflow for turborepo-caching usage

A practical workflow is:

1. Share your current monorepo layout and scripts.
2. Ask the agent to classify tasks into build, test, lint, dev, and persistent tasks.
3. Have it draft or revise turbo.json.
4. Ask it to justify every outputs, dependsOn, inputs, and env-related choice.
5. Run the tasks locally and compare cache hits and misses.
6. Return with logs or edge cases for a second pass.

The review step matters. Caching failures usually come from incorrect assumptions about outputs or hidden inputs.

Repository concepts to focus on

The skill content emphasizes a few core concepts that should guide how you use it:

• dependsOn controls execution ordering and upstream build relationships
• outputs determines what Turborepo can restore from cache
• inputs and global dependencies define what invalidates a cached result
• persistent is for long-running tasks and changes how they should be modeled

If your prompt does not address these, the agent may miss the real source of slow builds.

Practical example of a good review request

Use a request like this:

Apply the turborepo-caching skill to this turbo.json. Tell me which tasks are unsafe to cache, whether .next/** is too broad for my Next.js app, whether !.next/cache/** should be excluded, and whether my .env.local and VERCEL_URL should be in globalDependencies or globalEnv. Then propose a corrected config.

This is stronger than asking for “best practices” because it targets the exact knobs that control correctness.

What to inspect in your repo before asking

Before invoking the turborepo-caching skill, inspect:

• whether each package writes artifacts to a stable folder
• whether generated files live outside obvious output folders
• whether build scripts read from .env or CI-only variables
• whether tests generate snapshots, reports, or coverage outputs
• whether any script is non-deterministic

If outputs are unstable or inputs are hidden, caching will look broken even with a valid turbo.json.

Common install and adoption blockers

The biggest blocker is expecting the skill to infer your task graph from almost no context. The second is treating all scripts as cacheable. Development servers, watch mode, and other persistent processes usually need different handling. A third blocker is forgetting that environment variables can change the cache key, especially in frontend builds.

turborepo-caching skill FAQ

Is turborepo-caching useful for beginners

Yes, if you already have a Turborepo-based repo or are committed to using Turborepo. The skill gives structure to concepts beginners often mix up, especially outputs, dependsOn, and env-driven invalidation. It is less helpful if you are still deciding whether to adopt a monorepo tool at all.

How is this different from an ordinary prompt

A normal prompt may give generic monorepo advice. The turborepo-caching skill is narrower: it is oriented around Turborepo pipeline configuration and production caching patterns. That narrower scope usually produces better turbo.json recommendations and better debugging of cache misses.

When should I not use turborepo-caching

Skip this skill if:

• your repo does not use Turborepo
• you need package manager setup help more than cache design help
• your main problem is unrelated build correctness
• you want framework-specific deployment guidance rather than task caching

It is a configuration skill, not a universal performance optimizer.

Does the skill cover remote caching

Yes, at the decision level. The source material explicitly includes remote caching and CI/CD optimization as use cases. You should still provide your CI platform, secret management constraints, and whether developers should share cache artifacts across machines.

Can turborepo-caching help debug cache misses

Yes. That is one of its most practical uses. It can help review:

• missing or overly broad outputs
• hidden file or env dependencies
• bad task boundaries
• non-cacheable or persistent tasks modeled as normal builds

For debugging, include real examples of “this should have hit cache but did not.”

Is turborepo-caching only for large monorepos

No. Small monorepos also benefit if builds are frequent or CI is expensive. The skill becomes more valuable as the number of packages, apps, and pipelines grows, but it is still useful for a modest repo with a web app and shared packages.

How to Improve turborepo-caching skill

Give the agent your actual task graph

The fastest way to improve turborepo-caching results is to provide real scripts and package relationships. Include which packages depend on which, and which tasks consume upstream build outputs. Vague descriptions lead to generic cache templates that may be unsafe.

Be explicit about outputs

Most weak results come from under-specified output directories. Tell the agent exactly what each task writes. For example:

• apps/web build writes .next/
• packages/ui build writes dist/
• packages/config build writes generated .js and .d.ts files in lib/

That lets the agent produce a usable outputs list instead of guessing.

Surface environment-sensitive behavior

For turborepo-caching for Performance Optimization, env handling is often where correctness breaks. List:

• build-time env vars
• CI-only vars
• public frontend vars
• .env files that affect outputs

Ask the agent to separate values that should influence the cache key from values that should not.

Mark non-cacheable and persistent tasks early

A common failure mode is trying to cache everything. Improve results by telling the agent which tasks are:

• watch mode
• local dev servers
• long-running background processes
• side-effectful scripts such as deployments

This helps it avoid modeling persistent tasks like ordinary build steps.

Ask for reasoning, not just a config dump

A stronger turborepo-caching guide workflow is to request explanations for every major field. Example:

Revise my turbo.json and explain why each task has cache, outputs, and dependsOn configured the way it is. Flag any assumptions you had to make.

That makes mistakes easier to spot before you apply the config.

Validate with a second pass after running it

After the first output, run your tasks and return with observed behavior:

• which commands hit cache
• which commands miss unexpectedly
• whether restored artifacts are correct
• whether CI and local results differ

The second iteration is usually where the skill becomes most valuable, because real misses reveal hidden inputs the initial config could not infer.

Compare safe precision versus broad caching

When refining turborepo-caching usage, ask the agent to compare two options:

• conservative config with precise invalidation
• aggressive config for maximum cache reuse

This is a better decision framework than asking for “the best config,” because the right answer depends on your tolerance for stale artifacts versus compute cost.

Keep your prompt tied to measurable outcomes

Good improvement prompts mention concrete goals such as:

• cut CI build time by 40%
• avoid rebuilding apps/web when only docs change
• share build cache across developers
• eliminate repeated test runs for unchanged packages

Measurable goals help the agent choose between simpler and more granular pipeline designs.