The best alternatives to Sonar by Facebook are Videobug, Ray, and Reactime. If these 3 options don't work for you, we've listed a few more alternatives below.
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Videobug is a time travel debugger for your backend code. You can trace your past code executions line by line in your IntelliJ IDE.It works on localhost and cloud deployments. Try the Videobug plugin, it's free! No sign-up/sign-in is needed.
Ray is a beautiful desktop app to fix problems faster in PHP and JavaScript projects. Free demo: check https://myray.app/ 30% discount on Ray: https://spatie.be/products/ray?referrer=product%20hunt
With code-ray you can fix bugs in your code faster and easier. You can set breakpoints to show the live state in different sections of your code. code-ray can be linked to GitHub, GitLab and Bitbucket. There is a permanently free version.
Pluto is a on-device debugging framework for Android applications. It allows developer to build plugins over Pluto to inspect HTTP requests/responses, capture Crashes and ANR, manipulate application data on-the-go, inspect datbases, etc.