Normally, when using mythic, Mythic/mythic-react-docker and the mythic_react container serves a compiled version of the React UI.
For development, the Mythic/MythicReactUI folder holds the source code that gets built.
Modifying the Mythic UI
To load up the source code for active development, set the Mythic/.env variable mythic_react_debug to true and then run sudo ./mythic-cli build mythic_react. This will tear down the current mythic_react container and re-build it with nodejs.
At this point, any changes you make to the source code in Mythic/MythicReactUI will trigger automatic re-builds on the UI for easy development.
Building the Mythic UI
When you're done with all of your changes, run sudo ./mythic-cli build_ui and Mythic will automatically build the UI and place it in the mythic-react-docker folder. At this point, if you set the mythic_react_debug back to false and run ./mythic-cli build mythic_react, you'll see the UI exactly as somebody else would with a fresh install of Mythic.
Modifying permissions with GraphQL/Hasura
If you modify any of the permissions, create new actions, or make any modifications at all in Hasura's GraphQL, then you need to make sure those get saved off. There's not a great way to do this yet, but for now the following steps will save them when done from the Mythic directory:
docker exec -it mythic_graphql /bin/bash
[enter some random name here, let's say Bob]
cp /metadata/config.yml .
hasura-cli metadata export
cp * -R /metadata
The above steps export the metadata and puts it back into the mounted /metadata directory for Hasura.