# 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.

If you use additional React packages, you need to update Cljsjs packages
for these to use new React foreign-lib name, `react` instead of `cljsjs.react`.
**Subject to change, if this can be solved easily.**

## 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 `:shim-process` 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.