square/moshi
Moshi is a JSON serialization library for Java and Kotlin that provides both runtime reflection-based and compile-time code generation capabilities. The system supports serializing and deserializing Kotlin data classes, records, and custom types through adapters and generated code. It includes built-in adapters for common types and dates, with a modernized build system supporting KSP2 and Kotlin 2.3.
56.2
Adequate · 2 August 2026
13k
lines of production code
Kotlin
with Java
2
bus factor · 95 authors in all
3
measurements over time
How it got here
2014–2018 · Kotlin migration and test expansion
The project underwent a significant migration of the core library from Java to Kotlin, introducing breaking changes and new features like inline classes and KSP2 support. This period also focused on expanding test coverage and adding example recipes for common serialization patterns.
6 changes
2020–2022 · Kotlin codegen and migration
This period focused on modernizing the Moshi codebase by migrating internal Java components to Kotlin and introducing a new KSP-based code generation system. The team also expanded test coverage for the new reflection-based adapters and edge cases, while updating the build infrastructure to support these changes.
15 changes
Survey your own repository
square/moshi was measured the same way every project in this corpus was: the same rubric, at a pinned commit, with the result published in full. Point the surveyor at a repository you know and see whether you agree with it.
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 889013ec2e — 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.