Building a GitHub-like app can be a complex process that involves multiple components and technologies. Here are the general steps you can follow to build a GitHub-like app:

Define your requirements: Before you start building the app, you need to define your requirements. What are the key features you want your app to have? What are the user personas you are targeting? What are the technology requirements?

Choose your technology stack: Based on your requirements, you can choose the technology stack you want to use for building the app. GitHub uses a combination of technologies, including Ruby on Rails, MySQL, and Redis.

Design your database: Once you have chosen your technology stack, you need to design your database schema. GitHub uses a relational database to store its data, but you can choose any database that fits your requirements.

Build your user interface: The user interface is an essential part of any app. You can use front-end technologies like HTML, CSS, and JavaScript to build your user interface. GitHub uses a responsive web design that works well on desktop and mobile devices.

Implement your business logic: The business logic is the code that handles the core functionality of your app. You can use your chosen technology stack to implement your business logic. GitHub uses Ruby on Rails to implement its business logic.

Implement authentication and authorization: GitHub uses OAuth 2.0 for authentication and authorization. You can use any authentication and authorization mechanism that fits your requirements.

Implement version control: The core functionality of GitHub is version control. You can use Git or any other version control system to implement version control in your app.

Implement other features: Depending on your requirements, you may need to implement other features like issue tracking, pull requests, and code review. GitHub provides all these features, and you can implement them in your app too.

Test your app: Testing is an essential part of any app development process. You can use automated testing tools to test your app and ensure it works correctly.

Deploy your app: Once you have tested your app, you can deploy it to a production environment. GitHub uses a cloud-based infrastructure to host its app, but you can use any hosting provider that fits your requirements.

Building a GitHub-like app is a complex process that requires expertise in multiple technologies. You can hire a team of developers to build the app or use a low-code development platform to simplify the process.