This package (deep-eql) is used in chai latest version as a dependency. deep-eql package has a dependency from ["karma": "^0.13.22"](https://github.com/chaijs/deep-eql/blob/v3.0.1/package.json#L69) Using even the latest(v3.0.1) version of the deep-eql package I am getting the following error: ``` lerna ERR! execute Error: Command failed: npm install lerna ERR! execute npm WARN EBADENGINE Unsupported engine { lerna ERR! execute npm WARN EBADENGINE package: 'karma@0.13.22', lerna ERR! execute npm WARN EBADENGINE required: { node: '0.10 || 0.12 || 4 || 5' }, lerna ERR! execute npm WARN EBADENGINE current: { node: 'v16.13.1', npm: '8.1.2' } lerna ERR! execute npm WARN EBADENGINE } ``` Please see also the screenshot:  My suggestion is to update karma version to a newer one that supports a higher version of the nodejs.