lx (Log X-Ray)

Terminal-based log analysis tool. Paste logs, filter, annotate, copy.

# From clipboard
lx

# From file
lx app.log

# From pipe
kubectl logs pod-name | lx

# Live stream
docker logs -f container | lx

What It Does

• Parses JSON and plain text logs
• Filters by text pattern and log level
• Lets you annotate lines with notes
• Copies logs with annotations to clipboard
• Runs offline analytics on error patterns

What It Doesn't Do

• Persist anything to disk
• Connect to external services
• Handle files larger than available RAM
• Replace grep for simple searches

Install

Download Binary

Grab the latest release for your platform:

# Linux (amd64)
curl -L https://github.com/kalayciburak/lx/releases/latest/download/lx-linux-amd64 -o lx
chmod +x lx
sudo mv lx /usr/local/bin/

# macOS (Apple Silicon)
curl -L https://github.com/kalayciburak/lx/releases/latest/download/lx-darwin-arm64 -o lx
chmod +x lx
sudo mv lx /usr/local/bin/

# macOS (Intel)
curl -L https://github.com/kalayciburak/lx/releases/latest/download/lx-darwin-amd64 -o lx
chmod +x lx
sudo mv lx /usr/local/bin/

# Windows (PowerShell)
Invoke-WebRequest -Uri https://github.com/kalayciburak/lx/releases/latest/download/lx-windows-amd64.exe -OutFile lx.exe

Go Install

go install github.com/kalayciburak/lx/cmd/lx@latest

Build from Source

git clone https://github.com/kalayciburak/lx
cd lx
go build -o lx ./cmd/lx

Requires: Go 1.23+, terminal with Unicode support

Keybindings

Navigation

Key	Action
j / k	Move down / up
g / G	Jump to top / bottom
Enter	Toggle detail view
z	Maximize detail view

Filter

Key	Action
/	Open filter input
Tab	Cycle level (ALL → ERROR → WARN → INFO → DEBUG → TRACE)
Ctrl+R	Clear filter
Esc	Close filter

Notes

Key	Action
N	Add/edit note on current line
n	Toggle note visibility
m	Show/hide all notes
] / [	Jump to next/prev noted line
D	Delete note

Selection & Copy

Key	Action
s	Toggle selection on current line
S	Select all / clear selection
c	Copy selected lines (or current if none selected)
y	Copy all visible lines

Edit

Key	Action
d	Delete selected lines (or current)
x	Clear all lines
u	Undo delete
U	Redo delete
p	Paste from clipboard
o	Open file

Signal Analysis

Key	Action
1	Error frequency (top errors by count)
2	Lifetime (first/last occurrence of selected error)
3	Burst detector (error spike detection)
4	Diversity (error variety analysis)

Workspace

Key	Action
T	New workspace
W	Close workspace
Tab	Next workspace (when multiple open)
Shift+Tab	Previous workspace

Other

Key	Action
Ctrl+L	HTTP status code lookup
?	Help
q	Quit

Filter Syntax

error           → lines containing "error"
!debug          → lines NOT containing "debug"
error timeout   → lines with both "error" AND "timeout"
error !debug    → "error" but NOT "debug"

• Case-insensitive
• Multiple terms use AND logic
• Prefix ! for exclusion
• Filter applies to visible lines; y copies only filtered results

Notes

Notes are temporary annotations attached to log lines.

Add a note: Press N, type your note, press Enter

Note levels: Start with ! for critical, ? for unsure

!root cause         → marked as CRIT
?needs verification → marked as UNSURE
just a note         → normal

Copy behavior: When copying with c or y, notes are included:

=== NOTE (lx) ===
• [line 42] [CRIT] root cause

=== LOG ===
line 42: {"level":"error","msg":"connection refused"}

Persistence: Notes exist only in current session. Closing lx discards them.

Signal Analysis

Offline analytics for error patterns. No network, no database.

Signal	What it shows
1 Error Frequency	Top 10 most common ERROR messages
2 Lifetime	First/last occurrence of selected message
3 Burst Detector	Detects error spikes in short time windows
4 Diversity	Ratio of unique errors to total errors

Results are heuristic-based. False positives possible with unusual log formats.

Limitations

Limit	Value	Behavior when exceeded
Copy all (y)	1,000 lines	Shows error message
Select all (S)	3,000 lines	Shows error message
Text filter	15,000 lines	Text filter disabled, level filter still works

Large files: All logs are loaded into RAM. For files larger than available memory, use grep or head to reduce input size first.

Live streaming: Supported via pipe (docker logs -f container | lx). Exit with Ctrl+C.

Timestamps: Signal analysis requires parseable timestamps. Logs without timestamps show limited analytics.

Supported Formats

JSON:

{"msg":"error","level":"error","time":"2024-01-15T10:30:45Z"}
{"message":"ok","severity":"info"}

Plain text:

2024-01-15 10:30:45 ERROR Database timeout
[WARN] Disk space low

Stack traces: Java, Go, Python patterns auto-detected.

License

MIT

Author

kalayciburak