Daemonitor

Activity Monitor for your Gradle daemons — see what's building right now, and what built recently.

Daemonitor is a local desktop app that shows the Gradle activity happening on your machine: which daemons, wrappers, and test workers are running, how much memory and CPU they're using, the latest daemon-log lines, and a searchable history of past builds — including which AI coding agent triggered each build. It's built for the agentic-workflow era, where multiple IDEs, terminals, and agents can all be driving Gradle at once.

Everything stays on your machine. No telemetry, no network calls; command lines and logs are best-effort redacted before they're ever stored.

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Features

Live Monitor

Live monitor with concurrent Gradle activity and the selected daemon inspector.

• Every running Gradle-related JVM, classified by type with an at-a-glance icon:
  • 🐘 Gradle daemon · 🐘+🔧 Gradle wrapper · the Kotlin mark for the Kotlin daemon · 🧪 test worker · ☕ other Gradle-related JVM
• Per-process RSS, CPU, and live-ticking uptime
• Headline stats: active processes, total RSS, highest-memory PID, active projects
• Highlight badges: high/critical memory, MULTI-BUILD (a project with concurrent build invocations), AUTOMATED (CI/script/agent flags)
• Per-daemon detail with -Xmx, GC, working dir, full (redacted) command line, and a live tail of the daemon log
• One-click switch to headless mode from the toolbar when you want collection to continue without the desktop window

Historical

Build history with outcomes, source and agent tags, resource peaks, and a captured log excerpt.

• Every reconstructed build, with start time, project, duration, peak RSS, status (✓ success / ✗ failed / ⚠ interrupted / ◐ completed), source (terminal / IDE), and agent
• Filter by project and time range
• Per-build detail with resource peaks and a captured log excerpt

Settings

• Configurable history retention (default 15 days, range 1–90). Lowering it purges out-of-range entries immediately.

Headless collection

Daemonitor can keep collecting in the background without the desktop window. Use the toolbar action to switch from desktop to headless mode, or start it directly with --headless. Packaged headless mode uses the same local database and settings as the desktop app, shows a system tray/menu-bar icon when the OS supports it, and offers Open Daemonitor and Quit Daemonitor actions from that menu.

AI-agent attribution

Daemonitor fingerprints the coding agent behind a build from the environment-variable names the daemon recorded (names only — never values, staying within the redaction posture). It recognizes Claude Code, Cursor, Codex, Gemini CLI, and Aider, and flags unrecognized agents explicitly.

It also subtracts its own ambient environment before attributing: if Daemonitor itself runs inside, say, a Claude Code shell, every build would otherwise inherit those variables. Only signals that distinguish a build from Daemonitor's own session are attributed, so you don't get "everything is Claude."

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Requirements

• JDK 17+ to run Gradle from source. The build uses a Java 21 toolchain, which Gradle auto-provisions when a local Java 21 installation is unavailable.
• macOS, Linux, or Windows
• Permission to read your own process list and Gradle daemon logs

Daemonitor reads Gradle daemon logs under ~/.gradle/daemon/<version>/ and enumerates processes owned by the current user.

Install

Daemonitor is distributed as a native desktop app per operating system:

OS	Package
macOS	.dmg
Windows	.msi
Linux	.deb

The installed app does not require a project-local Gradle setup. It only reads local process metadata and Gradle daemon logs for the current user.

Run from source

Source builds require JDK 17+ to launch Gradle; the pinned Java 21 toolchain is provisioned automatically when it is not installed locally.

./gradlew run

To collect and persist data without starting Compose or requiring a display server:

./gradlew runHeadless

Packaged launchers also accept --headless. Headless and desktop modes use the same local database and retention setting. On desktop operating systems, the tray/menu-bar icon can reopen Daemonitor or quit the collector. Stop source-run headless mode with Ctrl+C or the service manager's normal termination signal.

Build a native distribution

The Compose Gradle plugin packages a platform-native installer via jpackage (must be built on the target OS):

./gradlew packageDmg          # macOS (.dmg)
./gradlew packageMsi          # Windows (.msi)
./gradlew packageDeb          # Linux (.deb)

Test

./gradlew test

The suite includes unit tests for the collection/classification/aggregation logic and Compose UI tests that mount the real screens and assert on rendered nodes. CI runs the full suite on Linux, Windows, and macOS (Linux uses a virtual display for the UI tests).

Updating README screenshots

The checked-in screenshots are rendered from synthetic, privacy-safe sample state using the real Compose screens at the application's native 1180×760 window size. After a visible UI change, run:

./gradlew captureReadmeScreenshots test

Review both files in docs/images/ before committing. Keep sample paths and logs synthetic; never capture a locally running instance with personal paths, environment values, or command-line secrets.

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How it works

Daemonitor combines two signals:

1. Process polling (via OSHI) every 2 s — RSS, CPU, uptime, and JVM flags for the current user's Gradle-related JVMs.
2. Daemon-log parsing — build existence, start/end, outcome, working directory, and the environment-variable names used for source/agent attribution.

A build is reconstructed by correlating a daemon's busy→idle bracket (which must contain a real build start) with the resource samples taken inside that window. Confirmed builds and samples are persisted to a local SQLite database (owner-only file permissions; excluded from Time Machine on macOS) and purged by the configured retention window.

Where data lives

OS	Path
macOS	~/Library/Application Support/Daemonitor
Linux	$XDG_DATA_HOME/Daemonitor (or ~/.local/share/Daemonitor)
Windows	%LOCALAPPDATA%\Daemonitor

Holds watcher.db (history) and settings.properties (retention).

Tech stack

Kotlin · Compose for Desktop (Material 3) · OSHI · SQLDelight + JDBC SQLite · Kotlin Coroutines.

Privacy

All data is local. Command lines and daemon-log lines may contain sensitive values, so they are redacted on a best-effort basis before storage, and the database file is created with owner-only permissions. Daemonitor never makes network requests.

Status

Early (v0.1.1). The data model and detection heuristics are evolving; see requirements.md for the original specification.