Ripgrep (rg) Documentation

A comprehensive guide to mastering ripgrep — the fastest code-search tool available. Written in Rust, rg is built for modern codebases: it is parallel, .gitignore-aware, regex-capable, and ergonomic by default.

Mental model: Think of rg as grep with the best defaults already set — no more --exclude-dir=node_modules, no more -rn, no more case complaints.

Curriculum

1. Introduction

• What is Ripgrep? — Why it exists and what makes it different.
• Installing rg — apt, brew, cargo, and Docker.

2. Core Syntax

• Basic Search — Pattern, path, and the implicit defaults.
• Multiple Patterns — OR logic, -e, and piping to a second rg.

3. Smart Defaults

• Gitignore Awareness — What rg ignores and why.
• Hidden and Ignored Files — -u, -uu, -uuu override ladder.

4. Regex & Patterns

• Regex Engine — Rust regex vs PCRE2 (-P).
• Anchors, Classes, and Quantifiers — Practical patterns for logs and code.
• Fixed Strings — When to use -F for speed and safety.

5. File & Type Filtering

• File Type Filters — -t py, -T json, and custom types.
• Glob Patterns — -g "*.conf" and negation.

6. Output & Context

• Context Lines — -A, -B, -C for stack traces.
• Formatting Flags — -l, -c, -n, --json, --vimgrep.

7. Performance & Tuning

• Parallel Search — Thread control and I/O tuning.
• Memory Maps and Large Files — --mmap, --no-mmap.

8. Real World Workflows

• Code Refactoring — Finding then replacing across projects.
• Log Analysis — Extracting IPs, errors, and JSON fields.
• Editor Integration — VSCode, Vim, fzf pipelines.

9. Troubleshooting

• No Results — Common Causes — Diagnosing hidden/ignored mismatches.
• Encoding and Binary Issues — -a, --encoding, and detection.

10. Cheatsheet

• Ripgrep Cheatsheet — All flags, quick reference tables, and pipelines.

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Quick start

# Install
cargo install ripgrep   # or: brew install ripgrep / apt install ripgrep

# Search any project instantly
rg "TODO"                       # search cwd, respects .gitignore
rg -t py "def process"         # only Python files
rg -l "API_KEY" /etc            # just file names
rg -C 3 "panic" logs/           # 3 lines of context