EditorConfig

EditorConfig enforces whitespace conventions at the editor level, before any linter or formatter runs. It works across all editors and IDEs without extra plugins (VS Code, JetBrains, Vim, Neovim, etc. all support it natively or via a free extension).

Setup

Copy this file to your project root as .editorconfig:

root = true

[*]
charset = utf-8
end_of_line = lf
indent_size = 2
indent_style = tab
insert_final_newline = true
trim_trailing_whitespace = true

# Markdown reads a tab as four spaces, so it uses spaces.
[*.{md,mdx}]
indent_style = space
trim_trailing_whitespace = false
max_line_length = off

# YAML does not allow tabs.
[*.{yml,yaml}]
indent_style = space
indent_size = 2

# Python's own style guide uses 4 spaces.
[*.py]
indent_style = space
indent_size = 4

No package installation required — EditorConfig is a file-based standard.

Rule reference

Rule	Value	Rationale
charset	utf-8	Universal default; avoids encoding issues on cross-platform teams
end_of_line	lf	Unix line endings everywhere; Windows devs should set core.autocrlf = input in git
indent_size	2	How wide a tab shows, and the indent for files that use spaces. Python uses 4
indent_style	tab	Tabs indent code. Each person sees the indent at the width they like, and files are smaller. Markdown, YAML and Python use spaces
insert_final_newline	true	POSIX standard; avoids noisy diffs when appending to files
trim_trailing_whitespace	true	Prevents invisible diff noise; disabled for Markdown where trailing spaces are significant

Markdown exception

In Markdown, two trailing spaces before a newline produce a <br> (hard line break). Trimming trailing whitespace would silently corrupt Markdown documents, so trim_trailing_whitespace = false is set for *.md files.

Files that use spaces

Files	Why
Markdown (*.md, *.mdx)	Markdown reads a tab as four spaces, which can break nested lists
YAML (*.yml, *.yaml)	YAML does not allow tabs
Python (*.py)	Python's own style guide uses 4 spaces

Alignment with other tools

The EditorConfig settings deliberately mirror the Prettier config:

• indent_style: tab ↔ useTabs: true
• indent_size: 2 ↔ tabWidth: 2
• end_of_line: lf ↔ endOfLine: "lf"

This means the editor writes the right whitespace from the start, and Prettier never has to fix it.