Ferrolog

A fast, lightweight TUI log viewer built in Rust. Open any log file and navigate, search, and filter entries without leaving your terminal.

Install

curl -fsSL https://raw.githubusercontent.com/ChrisJohnson89/Ferrolog/main/install.sh | bash

Installs to /usr/local/bin/ferrolog (falls back to ~/.local/bin without sudo).

Supported platforms:

Platform	Target
Linux x86_64	x86_64-unknown-linux-musl (static)
macOS Apple Silicon	aarch64-apple-darwin
macOS Intel	x86_64-apple-darwin

Usage

ferrolog <logfile>

# Examples
ferrolog /var/log/nginx/error.log
ferrolog /var/log/syslog
ferrolog app.log

Keybindings

Key	Action
j / ↓	Move down
k / ↑	Move up
g / Home	Jump to top
G / End	Jump to bottom
PgDn / PgUp	Scroll by 20
Enter	Toggle detail view
/	Search (live filter)
Esc	Exit search
1	Filter: TRACE
2	Filter: DEBUG
3	Filter: INFO
4	Filter: WARN
5	Filter: ERROR
6	Filter: FATAL
c	Clear all filters
?	Toggle help popup
q / Esc	Quit

Log Formats

Ferrolog auto-detects common formats:

• Nginx / Apache — [error] ... "message"
• Standard — [LEVEL] message, LEVEL: message
• Syslog — Jan 15 01:29:57 host service[pid]: message
• Logfmt — level=error msg="something happened"
• Unrecognised lines — shown as UNKNOWN and still navigable

Build from Source

Requires Rust stable.

git clone https://github.com/ChrisJohnson89/Ferrolog.git
cd Ferrolog
cargo build --release
./target/release/ferrolog <logfile>

Related

• Ferromon — system resource monitor TUI