GitHub - A web-based hosting service for software development projects.
DEV.TO - A constructive and inclusive social network for software developers.
CodePen - A social development environment for front-end designers and developers. Build and deploy a website, show off your work, build test cases.
Hashnode - A free developer blogging platform that allows you to publish articles on your own domain and helps you stay connected with a global developer.
CodeSandbox – An online code editor and prototyping tool that makes creating and sharing web apps faster.
StackOverflow - The largest, most trusted online community for developers to learn, share their programming knowledge, and build their careers.
AngelList - A website for startups, angel investors, and job-seekers looking to work at startups.
Snipplr - A place to keep code snippets, store and share all of your commonly used pieces of code and HTML with other programmers and designers.
GitLab - The DevOps Platform that provides a Git repository manager providing wiki, issue-tracking and continuous integration and deployment pipeline features.
Facebook - A lot of developers use it nowadays to connect with others by joining different Facebook groups.
WhatsApp groups - The speed of getting answers is the biggest advantage, developers can get the latest updates and useful info from the relevant community.
Instagram - The vast majority of developers love to use Instagram in their spare time.
Twitter - influencers start discussions, they ask followers to join in and share their views on various topics. By joining/following discussions, developers connect with each other.
YouTube - Developers use it to interact with other developers, to find solutions for the issues they encountered and to offer their original content.
Reddit - The most popular social network for developers - related to specific topics, such as different programming languages and frameworks.
Forums - Some of the most popular forums - CodeProject, XDA developers, Apple developer forum, salesforce developer forums, Drupal forum or WordPress forum etc.
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Social platforms where developers go to learn, ask devs questions.