AlternativeTo - AlternativeTo lets you find apps and software for Windows, Mac, Linux, iPhone, iPad, Android, Android Tablets, Web Apps, Online, Windows Tablets and more by recommending alternatives to apps you already know.
GitHub + Slack Integration - Full visibility into your GitHub projects right inside Slack
Ruby Toolbox - Explore and compare open source Ruby libraries
GitCommands - An interactive reference tool for Git commands
LibHunt - LibHunt tracks mentions of software libraries on relevant social networks. Based on that data, you can find the most popular projects and their alternatives.
ask-stack - Get answers from Stack Overflow directly in the Atom editor