# Biome @biomejs/biome@2.6.4 — Release & Upgrade Intelligence
- **Product:** Biome (https://biomejs.dev)
- **Version:** @biomejs/biome@2.6.4
- **Released:** Oct 28, 2026
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/biome/updates/biomejs-biome-2.6.4/

## Executive Summary (TL;DR)
Biome @biomejs/biome@2.6.4. Source highlight: Added the new nursery rule `noConsoleSpaces`, which reports a leading or trailing space in a `console.log()`, `console.debug()`, `console.info()`, `console.warn()`, or `console.error()` argument that sits next to another argument. These methods already put a space between arguments, so such a space 

## Bug Fixes
- Added the new nursery rule `noConsoleSpaces`, which reports a leading or trailing space in a `console.log()`, `console.debug()`, `console.info()`, `console.warn()`, or `console.error()` argument that sits next to another argument. These methods already put a space between arguments, so such a space prints twice.
- Added the new nursery rule `noMagicArrayFlatDepth`, which reports number literals other than `1` passed as the depth of `Array.prototype.flat()` unless a comment inside the parentheses explains them.
- Added the nursery rule `noNull`, which reports uses of the `null` literal and suggests `undefined` instead. Strict comparisons such as `foo === null` are allowed.
- Added the nursery rule `noReturnArrayPush`, which reports code that uses the return value of `push()` or `unshift()`. These methods return the new length of the array, not the added item or the array.
- Added the nursery rule `noUnreadableIife`, which reports arrow functions that are called right where they are defined and whose body is wrapped in parentheses.
- Added the nursery rule `noUselessRecursion`, which reports functions that return a call to themselves when a loop can do the same work. Too many nested calls can crash the program with a stack overflow error.

## Upgrade Command
```bash
npm install --save-dev --save-exact @biomejs/biome@2.6.4
```