For development purposes, you can use yarn link to have a local React app point to a local version of this project.
The only catch: You may run into the infamous error 13991 if you just yarn link this package alone.
Step 1
Instead, you'll need to yarn link this project and its copy of React, like this:
cd decode-client
yarn link
yarn install
cd node_modules/react
yarn link
cd YOUR_PROJECT
yarn link @decode/client
yarn link react
After following those steps, YOUR_PROJECT should be using the local copy of @decode/client.
(h/t: facebook/react#14257 (comment))
Step 2
Whenever you make changes to @decode/client, you'll need to build it for it to be picked up by YOUR_PROJECT.
However, yarn build does an rm -rf dist/, which can crash a local dev server of eg Create React App. So instead, you can run:
yarn build-dev
This will not rm -rf dist/ first, but instead overwrite files with new ones. This may result in some strangeness over time. Eg, if you rename a file, I believe the old file will still stick around in dist/. So if you're seeing strangeness, just run yarn build.