Floobits - Floobits brings real-time collaborative editing to text editors, IDEs, and now Atom.
GitHub Codespaces - GItHub Codespaces is a hosted remote coding environment by GitHub based on Visual Studio Codespaces integrated directly for GitHub.
codebunk - Realtime Collaborative Editor with Code Execution, REPLs and Chat
CloudShell - Cloud Shell is a free admin machine with browser-based command-line access for managing your infrastructure and applications on Google Cloud Platform.
coderpad - Collaborative code editor with in-browser, real-time execution. Conduct programming phone screens like a boss.
StackHive - Design, develop or publish websites right from your browser