Here is how to setup the condenser (the code that Steemit runs on) on your computer using the Steem testnet so you can make changes and debug the code without affecting real accounts on Steemit.
If you don't care about debugging locally then you can use the hosted testnet condenser here. https://condenser.steem.vc/
You can find the condenser here https://github.com/steemit/condenser follow the instructions to download the source code.
Refer to my previous post Understanding Steemit source code with Chrome DevTools for instructions how to run the source code in debug mode.
We're going to make an additional change before running the docker container to get it to connect to the testnet.
In package.json find the line
"start": "node scripts/check_translations.js; NODE_ENV=development ./node_modules/babel-cli/bin/babel-node.js ./webpack/dev-server.js",
and change it to
"start": "node scripts/check_translations.js; NODE_ENV=development SDC_ADDRESS_PREFIX=\"STX\" SDC_CHAIN_ID=\"79276aea5d4877d9a25892eaa01b0adf019d3e5cb12a97478df3298ccdd01673\" SDC_SERVER_STEEMD_URL=\"wss://testnet.steem.vc\" SDC_CLIENT_STEEMD_URL=\"wss://testnet.steem.vc\" ./node_modules/babel-cli/bin/babel-node.js ./webpack/dev-server.js",
We have now added the testnet connection strings. Notice how we escape the quotes in the environment var with \ so we don't break the string.
That's it. Now build the docker container again like i mentioned in the previous post.
docker build -t condenser .
And run it.
docker run -it -p 8080:8080 condenser
Now open Chrome and go to http://localhost:8080/
You will Steemit running on the testnet.
See nothing is trending because its the testnet.
You normal Steemit account wont work on the testnet. Account creation is disabled trough it so you still need to use the testnet API to create accounts, see here for instructions.
Now you can test what ever code you like locally and it wont affect Steemit.
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