logview

A per-app log filter for Turborepo. When turbo dev runs apps/* in one terminal, the output from every app is interleaved and hard to read. logview wraps the command, colors each app, pins a filter badge bar to the top of the terminal, and lets you toggle apps on and off from an interactive dropdown.

It works with anything that prefixes lines with [app-name] — Turborepo, npm workspaces, pnpm --parallel, etc. Zero dependencies, Node 16+.

 logview  f=filter  1-9=toggle  a=all  n=none  /=search  q=quit
1[core-services] 2[admin-console] 3[auth-api] 4  analytics-api   5[web-app]
────────────────────────────────────────────────────────────────────────────
[core-services] [10:51:50 AM] Starting compilation in watch mode...
[auth-api]      [10:52:04 AM] Found 0 errors. Watching for file changes.
[admin-console]  ○ Compiling /src/middleware ...

Apps shown as a solid colored badge are visible; dimmed ones are hidden (above, analytics-api is hidden).

Install

It's a single file. Pick whichever fits your team:

Option A — run it directly (no install)

node logview.js turbo dev

Option B — install into the repo so everyone gets a logview command

From the folder containing package.json:

npm link          # or: npm install -g .
logview turbo dev

Option C — drop it in your monorepo and add a script

In your root package.json:

{
  "scripts": {
    "dev": "node ./tools/logview.js turbo dev"
  }
}

Usage

logview turbo dev            # wrap turbo and filter interactively
logview pnpm dev             # any command works
logview --only auth-api,core-services turbo dev   # start pre-filtered
logview --hide admin-console turbo dev            # start with some hidden

Interactive keys

| Key | Action | |------------|---------------------------------------------------| | f | open the app filter dropdown | | 1–9 | toggle an app on/off by its number | | a | show all apps | | n | hide all apps | | / | search — type text, Enter to apply, Esc clears | | wheel / ↑ ↓ | scroll through history (pauses the live tail) | | PgUp / PgDn | scroll a page at a time | | Home / g | jump to the oldest buffered line | | End / G | jump back to the live tail | | q | quit (also stops the wrapped command) |

In the dropdown: ↑/↓ move, space toggles the highlighted app, a/n all/none, Enter or Esc closes.

Scrolling back through old logs

Scroll up with the mouse wheel (or ↑ / PgUp) to review earlier output — the live tail pauses while you read and the header shows ⏸ scrolled +N so you know new lines are being buffered, not lost. Press End (or G) to snap back to the bottom and resume following. The last 10,000 filtered lines are kept in memory, and changing the filter re-applies to that whole history.

Because the wheel is used for scrolling, click-drag text selection needs Shift+drag while logview is running (standard for terminal apps that capture the mouse).

Try it without turbo

A demo emitter is included:

npm run demo        # == node logview.js node demo.js

Terminal support (Windows)

Works in Git Bash, PowerShell, and Windows Terminal. The pinned badge bar uses standard ANSI scroll regions, supported by the modern Windows console (Windows 10 1903+ / Windows Terminal). If you're on a very old console and the header looks off, use plain mode (below).

Git Bash

node logview.js turbo dev

PowerShell

node .\logview.js turbo dev

Non-interactive / pipe mode

For CI, log files, or when you just want a filtered stream with no UI:

turbo dev | logview --only auth-api        # pipe mode (no keyboard UI)
logview --no-ui --hide admin-console turbo dev

In pipe mode the keyboard controls are unavailable (stdin is the log stream), so use --only / --hide to choose what shows.

Notes

• Lines with no [app] prefix (turbo banners, multi-line stack traces) are grouped with the most recent app so a message stays together when filtered.
• Because logview takes over the keyboard for its controls, keystrokes are not forwarded to the wrapped dev server. If your workflow depends on typing into next dev (e.g. its interactive prompts), run that app on its own or use --no-ui.