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yek

A fast Rust based tool to serialize text-based files in a repository or directory for LLM consumption.[^1]

By default:

Yek يک means "One" in Farsi/Persian.

Consider having a simple repo like this:

.
├── README.md
├── src
│   ├── main.rs
│   └── utils.rs
└── tests
    └── test.rs

Running yek in this directory will produce a single file and write it to the temp directory with the following content:

>>>> README.md
... content ...
>>>> tests/test.rs
... content ...
>>>> src/utils.rs
... content ...
>>>> src/main.rs
... content ...

[!NOTE]
yek will prioritize more important files to come last in the output. This is useful for LLM consumption since LLMs tend to pay more attention to content that appears later in the context.

Installation

Choose the installation method for your platform:

Unix-like Systems (macOS, Linux)

curl -fsSL https://bodo.run/yek.sh | bash

For Windows (PowerShell):

irm https://bodo.run/yek.ps1 | iex
Build from Source
git clone https://github.com/bodo-run/yek
cd yek
cargo install --path .

Usage

yek has sensible defaults, you can simply run yek in a directory to serialize the entire repository. It will serialize all files in the repository and write them into a temporary file. The path to the file will be printed to the console.

Examples

Process current directory and write to temp directory:

yek

Pipe output to clipboard (macOS):

yek src/ | pbcopy

Cap the max output size to 128K tokens:

yek --tokens 128k

[!NOTE] yek will remove any files that won't fit in the capped context size. It will try to fit in more important files

yek --max-size 100KB --output-dir /tmp/yek src/

Process multiple directories:

yek src/ tests/

Process multiple files

yek file1.txt file2.txt file3.txt

Use glob patterns:

yek "src/**/*.ts"
yek "src/main.rs" "tests/*.rs" "docs/README.md"

[!NOTE] When using glob patterns, make sure to quote them to prevent shell expansion.

CLI Reference

yek --help
Usage: yek [OPTIONS] [input-paths]...

Arguments:
  [input-paths]...                Input files and/or directories to process

Options:
      --no-config                              Do not use a config file
      --config-file <CONFIG_FILE>              Path to the config file
  -V, --version                                Print version of yek
      --max-size <MAX_SIZE>                    Max size per chunk. e.g. "10MB" or "128K" or when using token counting mode, "100" or "128K" [default: 10MB]
      --tokens <TOKENS>                        Use token mode instead of byte mode
      --json                                   Enable JSON output
      --debug                                  Enable debug output
      --line-numbers                           Include line numbers in output
      --output-dir [<OUTPUT_DIR>]              Output directory. If none is provided & stdout is a TTY, we pick a temp dir
      --output-name [<OUTPUT_NAME>]            Output filename. If provided, write output to this file in current directory
      --output-template [<OUTPUT_TEMPLATE>]    Output template. Defaults to ">>>> FILE_PATH\nFILE_CONTENT"
      --ignore-patterns <IGNORE_PATTERNS>...  Ignore patterns
      --unignore-patterns <UNIGNORE_PATTERNS>... Unignore patterns. Yek has some built-in ignore patterns, but you can override them here.
  -t, --tree-header                            Include directory tree header in output (incompatible with JSON output)
      --tree-only                              Show only the directory tree (no file contents, incompatible with JSON output)
  -h, --help                                   Print help

CLI Options Detail

Configuration File

You can place a file called yek.yaml at your project root or pass a custom path via --config-file. The configuration file allows you to:

  1. Add custom ignore patterns
  2. Define file priority rules for processing order
  3. Add additional binary file extensions to ignore (extends the built-in list)
  4. Configure Git-based priority boost
  5. Define output directory and output filename
  6. Define output template and other output options

Configurable Options

Most CLI options can be configured in the config file. The following options can be set:

File Processing:

Output Configuration:

Config-only Options:

[!NOTE] Some CLI options like --no-config, --config-file, and --version are CLI-only and cannot be set in config files.

Example yek.yaml

You can also use yek.toml or yek.json instead of yek.yaml.

This is optional, you can configure the yek.yaml file at the root of your project.

# Add patterns to ignore (in addition to .gitignore)
ignore_patterns:
  - "ai-prompts/**"
  - "__generated__/**"

# Configure Git-based priority boost (optional)
git_boost_max: 50 # Maximum score boost based on Git history (default: 100)

# Define priority rules for processing order
# Higher scores are processed first
priority_rules:
  - score: 100
    pattern: "^src/lib/"
  - score: 90
    pattern: "^src/"
  - score: 80
    pattern: "^docs/"

# Add additional binary file extensions to ignore
# These extend the built-in list (.jpg, .png, .exe, etc.)
binary_extensions:
  - ".blend" # Blender files
  - ".fbx" # 3D model files
  - ".max" # 3ds Max files
  - ".psd" # Photoshop files

# Output configuration
max_size: "128K"           # Size limit (can also use tokens: "100k")
json: false                # Enable JSON output
debug: false               # Enable debug logging
line_numbers: false        # Include line numbers in output
tree_header: false         # Include directory tree at start

# Define output directory
output_dir: /tmp/yek

# Define output filename (writes to current directory with this name)
output_name: yek-output.txt

# Define output template.
# FILE_PATH and FILE_CONTENT are expected to be present in the template.
output_template: "FILE_PATH\n\nFILE_CONTENT"

Performance

yek is fast. It's written in Rust and does many things in parallel to speed up processing.

Here is a benchmark comparing it to Repomix serializing the Next.js project:

time yek
Executed in    5.19 secs    fish           external
   usr time    2.85 secs   54.00 micros    2.85 secs
   sys time    6.31 secs  629.00 micros    6.31 secs
time repomix
Executed in   22.24 mins    fish           external
   usr time   21.99 mins    0.18 millis   21.99 mins
   sys time    0.23 mins    1.72 millis    0.23 mins

yek is 230x faster than repomix.

Roadmap

See proposed features. I am open to accepting new feature requests. Please write a detailed proposal to discuss new features.

Alternatives

License

MIT

[^1]: yek is not "blazingly" fast. It's just fast, as fast as your computer can be.

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