Pacwich

Pacwich is command-line tooling for managing monorepos built with Bun, npm, or pnpm workspaces. It orchestrates package.json scripts across multiple packages, tracks which workspaces are affected by changes, and enforces code-sharing rules without locking you into a single package manager. The goal is a lightweight alternative to full-featured monorepo frameworks when all you need is script orchestration and dependency awareness without the configuration overhead. If you have five packages and want to run tests only on the ones that changed, Pacwich does that without requiring you to adopt an entire philosophy about how to structure your repository.

The problem it addresses is familiar to anyone maintaining a multi-package JavaScript or TypeScript repository. Running builds, tests, linting, or any other script across packages requires tracking dependencies between them, ordering execution correctly, caching outputs where possible, and handling changes that ripple through the dependency graph. Heavy tools like Nx and Turborepo solve this well but come with significant configuration overhead, proprietary concepts, and opinions about how your repository should be structured. You adopt their way of thinking, learn their vocabulary, and configure their systems. For some teams that investment pays off. For others it is more weight than the problem deserves. Pacwich aims for a smaller surface area, focusing on the orchestration layer while staying out of the way on everything else.

Under the hood it provides an affected graph that identifies which workspaces changed based on git history and dependency links. When you run a command, Pacwich figures out which packages need to run it based on what files changed since a reference point, typically your main branch or the last successful CI run. You can configure what counts as a change, exclude paths that should not trigger rebuilds, and debug the graph when something looks off. This affected filtering is the core value for CI pipelines where running every package every time is wasteful. If only two packages changed, only two packages run, and your CI finishes faster without manual intervention to skip steps.

Workspace rules let you enforce policies across packages. You can require certain dependencies to be present, ensure scripts follow naming conventions, or flag packages that drift from your standards. This is useful in larger teams where consistency matters and manual code review cannot catch every deviation. Instead of relying on convention and goodwill, you encode the rules and the tool checks them automatically. Violations surface early rather than accumulating as technical debt.

Configuration lives in JSON or TypeScript files depending on your preference. The TypeScript option lets you define rules programmatically and share logic between configuration and other tooling in your repository. For simpler setups, JSON works fine and keeps the configuration declarative. Either way, the configuration is explicit and version-controlled rather than buried in UI settings or undocumented scripts.

Pacwich offers both a CLI and a TypeScript API, so you can run it from npm scripts or integrate it programmatically into custom tooling. If you have a bespoke build system or need to embed workspace awareness into a larger automation layer, the API makes that possible without shelling out to the CLI. A browser-based demo lets you try commands against a sample repository without installing anything locally, which is helpful for evaluating whether it fits your workflow before adding it to your project.

The target audience is developers building TypeScript or JavaScript monorepos who want script orchestration decoupled from their package manager choice. It fits teams who find existing monorepo tools too heavy for their needs and want something they can understand in an afternoon rather than a week. If you have a handful of packages and want to run tests only on affected workspaces without adopting an entire framework, Pacwich is sized for that use case.

Pacwich is a continuation of the deprecated bun-workspaces package, with minimal breaking changes for existing users. If you were using bun-workspaces and looking for a maintained successor, Pacwich is that path. The maintainer is Scott Morse under Smorsic Labs, and the project is open source on GitHub with active development.

The product also leans into AI integrations, supporting Skills, AGENTS.md, MCP Server, and a /llms.txt file for AI assistants. This is unusual for build tooling but signals a direction toward AI-assisted monorepo management where agents can query the dependency graph or run commands on your behalf. As AI coding tools become more common, having a build tool that understands how to expose its state to those tools becomes an advantage.

Pricing is not listed, and the distribution via npm suggests open source with no paid tier. The focus is on developer adoption rather than monetization, which means you can try it on your repository without commercial concerns or license negotiations.