Codesandbox.io: Great for React, cannot accept POSTs
#frontend

Codepen.io: Great for CSS, though it does support React, JS, HTML & Pug
#frontend

For just frontend deployment, see now.sh & netlify. Really quick simple deployments now.

#Fullstack (include a VM/Container for development)

Codeanywhere, $8/mo

Stackblitz: VSCode in the Cloud

Glitch.com 
#fullstack

Runkit
#backend

Jsbin

Repl.it
#backend

Archived

C9.io: Was really nice, but it’s been bought by Amazon; not free anymore, unless you use AWS 😭
#fullstack

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