---
title: "fast-uri Breaking Changes on npm | Since.dev"
description: "What each fast-uri release removed, renamed or changed: 4 breaking changes in 1 version on npm, each with its source."
canonical_url: https://since.dev/packages/npm/fast-uri
last_updated: 2026-10-19
---

# fast-uri breaking changes

Every breaking API change we have recorded in fast-uri on npm: 4 breaking changes in 1 version. Below are its newest version, removals and renames first, each with its source.

Newest change October 19, 2026

## 3.1.9

4 breaking changes, first published October 19, 2026.

- **Behavior changed**  

Domain hosts with ambiguous delimiters or stripped control characters now raise an error instead of being silently rewritten. Callers must supply well-formed hosts. [github.com](https://github.com/fastify/fast-uri/releases/tag/v3.1.9)
- **Behavior changed**  

Path-only suffix references whose first segment contains a colon are now escaped, so the output string differs from earlier versions. [github.com](https://github.com/fastify/fast-uri/releases/tag/v3.1.9)
- **Behavior changed**  

Relative-reference normalization now preserves resolution semantics, so resolved output for some relative references may differ from earlier versions. [github.com](https://github.com/fastify/fast-uri/releases/tag/v3.1.9)
- **Behavior changed**  

Schemes written with percent-encoding, such as ht%74ps:, are no longer decoded into a live scheme and are treated as malformed. Code that relied on that decoding must pass the plain scheme. [github.com](https://github.com/fastify/fast-uri/releases/tag/v3.1.9)

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---

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