# 0.8 Upgrade guide

The necessary changes depend on what environment you target, and
how you want to provide React.

## Browser - Cljsjs

Using Reagent itself with Cljsjs packages doesn't require changes,
other than making sure you depend on the latest Cljsjs React packages,
if you have direct dependencies to them.

## Browser - node modules

You can use `:npm-deps` and `:install-deps` compiler options to
install the packages automatically.

If `react`, `react-dom` and `create-react-class` are available in `node_modules`
directory, ClojureScript compiler will use these with Reagent. **This
doesn't depend on use of `:npm-deps` option!** `:npm-deps` option is only about
installing the dependencies, if packages are available in `node_modules`
directory, they will be used.

You can use `:process-shim` compiler option to provide `process.env.NODE_ENV`
constant which is used by JS code to enable development and production
builds. ClojureScript compiler will automatically set this constant to
`production` value when using `:advanced` optimizations. This enables
the React production build.

## NodeJS

Install `react`, `react-dom` and `create-react-class` npm packages,
and ClojureScript should automatically use `require` to
load React for Reagent.

## Electron

???

## React-native

https://github.com/drapanjanas/re-natal/issues/128

## Common Problems

### Mismatch with Cljsjs and npm packages

If you have one npm package installed, e.g. `react`, you also need
to provide others (`react-dom` and `create-react-class`), else
Cljsjs packages would be used for these, and packages from different sources
don't work together.