---
title: "@fastify/busboy Breaking Changes on npm | Since.dev"
description: "What each @fastify/busboy release removed, renamed or changed: 26 breaking changes in 2 versions on npm, each with its source."
canonical_url: https://since.dev/packages/npm/@fastify/busboy
last_updated: 2026-08-12
---

# @fastify/busboy breaking changes

Every breaking API change we have recorded in @fastify/busboy on npm: 26 breaking changes in 2 versions. Below are its newest 2 versions, removals and renames first, each with its source.

Newest change August 12, 2026

## 3.2.1

25 breaking changes, first published August 12, 2026.

- **Removed** `Busboy.addListener`  

Busboy.addListener was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Removed** `Busboy.off`  

Busboy.off was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Removed** `Busboy.on`  

Busboy.on was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Removed** `Busboy.once`  

Busboy.once was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Removed** `Busboy.prependListener`  

Busboy.prependListener was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Removed** `Busboy.prependOnceListener`  

Busboy.prependOnceListener was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Removed** `Busboy.removeListener`  

Busboy.removeListener was removed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Signature changed** `Busboy`  

The signature of Busboy changed in @fastify/busboy 3.2.1 [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Signature changed** `BusboyConstructor.__call`  

Was (options: BusboyConfig): Busboy; now (options: BusboyConfig): BusboyInstance. [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)
- **Signature changed** `BusboyConstructor.__new`  

Was new(options: BusboyConfig): Busboy; now new(options: BusboyConfig): BusboyInstance. [npmjs.com](https://www.npmjs.com/package/@fastify/busboy/v/3.2.1)

And 15 more in this version.

## 3.2.0

1 breaking change, first published August 16, 2025.

- **Behavior changed**  

Quoted Content-Disposition parameters are now parsed under stricter RFC 2183/7578 rules, which can change parsed field or file names for some requests. [github.com](https://github.com/fastify/busboy/releases/tag/v3.2.0)

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