nocb

nearly optimal clipboard manager - fast, compressed, hash-based storage

features

• hash-based storage - blake3 content addressing, instant deduplication
• compression - automatic zstd compression for text >4KB
• images - full support with dimensions (png/jpeg/gif/bmp/webp)
• performance - sqlite with WAL, LRU cache, 100MB entry support
• security - unix socket with uid verification, memory zeroization
• rofi integration - 80-char entries with hash-based retrieval

install

cargo install --path core
# or
cargo build --release
cp target/release/nocb ~/.local/bin/

usage

daemon setup

# manual start
nocb daemon

# systemd service
cat > ~/.config/systemd/user/nocb.service << EOF
[Unit]
Description=NOCB Clipboard Manager
After=graphical-session.target

[Service]
Type=simple
ExecStart=$HOME/.local/bin/nocb daemon
Restart=on-failure
Environment="DISPLAY=:0"

[Install]
WantedBy=default.target
EOF

systemctl --user enable --now nocb

usage

# minimalistic use with fzf
nocb print | fzf | nocb copy

keybindings

# sxhkd with rofi example
echo 'super + b
    ~/.local/bin/nocb print | rofi -dmenu -i -p "clipboard" | ~/.local/bin/nocb copy' >> ~/.config/sxhkd/sxhkdrc

commands

nocb print                      # list history (newest first)
nocb copy <selection>           # copy by selection or hash
nocb clear                      # wipe all history
nocb prune <hash1> <hash2>      # remove specific entries

display format

3m use anyhow::{Context, Result}; use arboard… #b9ef2033
27s Preview of large text file… [38K] #a7c4f892
1d [IMG:1920x1080px png 256K] #d8e9f023

• time - relative timestamp (s/m/h/d)
• content - truncated to fit 80 chars
• size - file size for large entries
• hash - 8-char prefix for retrieval

configuration

~/.config/nocb/config.toml:

cache_dir = "~/.cache/nocb"
max_entries = 10000
max_display_length = 200
max_print_entries = 1000
blacklist = ["KeePassXC", "1Password"]
trim_whitespace = true
compress_threshold = 4096
static_entries = []  # pinned entries

storage

• database: ~/.cache/nocb/index.db - metadata, hashes, timestamps
• blobs: ~/.cache/nocb/blobs/ - compressed text, images
• socket: /tmp/nocb.sock - ipc with uid verification

implementation

• rust with tokio async runtime
• arboard for cross-platform clipboard
• sqlite with prepared statements
• zstd compression level 3
• lru cache for recent entries
• non-blocking clipboard polling

requirements

• rust 1.70+
• x11 or wayland (linux)
• systemd (optional)

license

MIT