gulp-config-grabber
Combine multiple config.json files using a flag to distinguish different environments.
configstore-ts
Lightweight typescript configuration handler, supporting config files and default values.
ngx-config-json
This is a simple Angular service which loads a config.json on application statup and allows to inject the config model into your angular components.
config-tree
A reworking of npm's init-package-json to make reusable prompt-based CLIs for making config.json files.