PUBLIC PACKAGE WORKBENCH
Check the declaration.
Verify the published files.
Check an exact release against your Node.js target, then optionally inspect its published files, module scopes and static imports. Share evidence with source locations in a PR or Issue.
Choose an exact public npm release, target Node.js version and CommonJS or ESM. The checker reads declarations without installing or executing packages.
Understand the signals
Browse explanationsHow to investigate ERR_REQUIRE_ESM
Understand why require() reaches an ES module, how Node versions change the result, and when to use import() or migrate to ESM.
Node version requirementsHow to resolve a Node engine mismatch
Read engines.node ranges, investigate npm EBADENGINE warnings, and align local, CI, and deployment Node versions.
Package entry pointsHow conditional exports choose a package entry
Understand import, require, node, and default export conditions, why their order matters, and what metadata cannot prove.
Semver and dependency selectionHow npm version ranges affect compatibility
Read caret and tilde ranges, understand 0.x and prerelease behavior, and separate a declared range from an installed version.