dependencies are the packages your project depends on.
devDependencies are the packages that are needed during the development phase. Say a testing framework like Jest or other utilities like Babel or ESLint.
In both cases, when you install a package, its dependencies and devDependencies are automatically installed by npm.
peerDependencies are different. They are not automatically installed.
When a dependency is listed in a package as a peerDependency, it is not automatically installed. Instead, the code that includes the package must include it as its dependency.
npm will warn you if you run npm install and it does not find this dependency.
haoyunfeix
commented
4 years ago
dependencies are the packages your project depends on.
devDependencies are the packages that are needed during the development phase. Say a testing framework like Jest or other utilities like Babel or ESLint.
In both cases, when you install a package, its dependencies and devDependencies are automatically installed by npm.
peerDependencies are different. They are not automatically installed.
When a dependency is listed in a package as a peerDependency, it is not automatically installed. Instead, the code that includes the package must include it as its dependency.
npm will warn you if you run npm install and it does not find this dependency.