RAZKOMtail, but tailored.
hem app.log opens a full-screen, mouse-aware log viewer that makes it obvious where things went wrong. It stays instant on multi-gigabyte files and never gets in the way of the program writing them.
01install
cargo
cargo install hemcargo-binstall
cargo binstall hemmacOS / Linux
curl --proto '=https' --tlsv1.2 -LsSf https://github.com/RAZKOM/hem/releases/latest/download/hem-installer.sh | shWindows
powershell -ExecutionPolicy Bypass -c "irm https://github.com/RAZKOM/hem/releases/latest/download/hem-installer.ps1 | iex"Or grab a prebuilt archive from GitHub Releases. Inside the viewer, press ? for help and : for the command palette.
02what it does
Instant on huge filesIndexed in the background: a 5 GB log is scrollable in ~20 ms and fully indexed in a few seconds.
Answers "what happened?"A timeline minimap coloured by severity, next / previous error, and repeats collapsed with counts and sparklines.
Rare lines firstThe templates view groups lines by shape, so the one odd message stands out from a million routine ones.
Filters that composeRegex include and exclude, minimum level, time range and field predicates like
status>=500, as clickable chips.Out of the writer's wayFiles are read without memory-mapping, so the app writing the log can still rotate, truncate or delete it. On Windows too.
A proper Unix toolFiles, globs, stdin and
.gz; merge sources by timestamp; plain coloured output when piped.03usage
hem app.log # open in the viewer hem app.log nginx.log --merge # one stream, interleaved by timestamp hem 'logs/*.log' # globs are expanded by hem cat app.log | hem # stdin hem app.log -f # follow, survives rotation hem app.log --since 15m --level warn --filter timeout hem app.log --level error --plain | wc -l hem templates app.log -n 20 --rare # the 20 rarest line templates
04spec
| platform | Windows, macOS, Linux (x64 and ARM64) |
| formats | JSON lines, logfmt, nginx / Apache, syslog, plain; custom formats in config |
| stack | Rust + ratatui |
| install | cargo install hem or a one-line installer |
| config | Optional TOML: themes, colours, keys, presets |
| license | MIT or Apache-2.0 |
| cost | Free |