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The Deno Standard Library
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Architecture Guide

This guide aims to explain how this codebase is organized.

File Structure


This folder contains internal tools that are used in CI and development for checking code and performing codebase transformations, such as preparing the codebase for JSR.


Each package is encapsulated as a top-level folder, without the prepended underscore in the name.


These files are typically the entry points for their respective packages. They export all public symbols within that package. For example, foo/mod.ts.


The source files are where APIs are implemented. Each file exports APIs that are highly likely to be used together. This sometimes means the source file only exports one or two APIs, as they are unlikely to be used with another specific API. In most cases, the name of the source file is the name of the main API that it implements, snake cased. For example, foo/bar.ts contains the implementation of the Bar class.


Each source file comes with a corresponding test file. The test file contains the tests for the APIs within the source file. For example, the source file, foo/bar.ts, has test file, foo/bar_test.ts.


This is the configuration file for this codebase. It contains settings and tasks that apply to the codebase as a whole.