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expressjs/express

This system is a web application framework that provides middleware for routing, session management, and error handling. It supports multiple template engines, including EJS and Handlebars, and offers examples for static file serving, content negotiation, and API key validation. The codebase also includes comprehensive test coverage and dependency management for Node.js applications.

44.8

Weak · 2 August 2026

6.4k

lines of production code

JavaScript

primary language

2

bus factor · 393 authors in all

3

measurements over time

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How it got here

2009–2011 · Project initialization and example expansion

This period focused on establishing the project's foundational structure, including core application logic, configuration files, and comprehensive test coverage. It also involved expanding the examples directory with diverse use cases such as authentication, session management, and content negotiation, while migrating template engines to EJS.

18 changes

2012 · expansion of example applications

This period focused on significantly expanding the project's example suite, introducing a wide variety of new demonstration applications. These additions covered diverse patterns such as MVC architecture, error handling, middleware usage, and integrations with external services like Redis and vhost.

14 changes

2013–2017 · Example modernization and expansion

This period focused on expanding the project's example suite with new demonstrations for routing, resource management, and error handling. Concurrently, existing examples were updated to adopt modern JavaScript practices, including strict mode, EJS templates, and responsive HTML5 structures.

13 changes

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About this page

  • The description of this project is derived from its own commit history, not from its README.
  • The score is its highest published measurement, taken on 2 August 2026 at a pinned commit. It is not a live figure and does not change until the project is measured again.
  • Measured at commit a3714473fe — the exact code this score is about.
  • Scored under rubric rubric-2026.08.18. Score the same commit under that rubric and you get the same number.
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