Mimick for Linux

A daemon-based synchronization tool for uploading media files from a Linux desktop to an Immich server.

Mimick monitors local directories (e.g., ~/Pictures, ~/Videos) for new files and automatically uploads them to your Immich instance. It runs securely as a background service and integrates natively with the GNOME desktop environment via a GTK4 / Libadwaita settings window and a StatusNotifier system tray icon.

Note

This project is in BETA. Core features are stable and tested. Please report any issues or edge cases you encounter.

Status: Beta. Supports Immich v1.118+.

Screenshots

Settings Window	System Tray Menu
Ping Test Dialog	About Dialog

Features

• File Monitoring: Watches selected folders for new files and waits for stable size before uploading.
• SHA-1 Checksumming: Deduplication via checksum before upload — exact same logic as the Immich mobile apps.
• Concurrent Uploads: 10 parallel worker tasks stream files directly from disk, keeping RAM usage constant.
• Offline Reliability: Failed uploads are persisted to ~/.cache/mimick/retries.json and replayed automatically on next launch.
• Connectivity: Automatically switches between Internal (LAN) and External (WAN) URLs based on availability. At least one must be enabled (enforced by the UI).
• Custom Album Mapping: Select an existing remote album, type a custom name, or let the app create an album from the local folder name (e.g., ~/Pictures/Vacation 2024 → Album Vacation 2024).
• One-Way Sync: Uploads media without modifying local files.
• Security: API Key stored in the system keyring via secret-tool (libsecret).
• Autostart: Optional login startup with desktop-portal permission inside Flatpak and native autostart integration outside Flatpak.
• Startup Catch-Up: On launch, Mimick scans watched folders for media that has not been synced yet and queues only new, changed, or retargeted files.
• Clear Window Controls: Close hides the settings window, while Quit stops the app completely.
• Desktop Integration:
  • GTK4 / Libadwaita settings UI (dark mode by default).
  • StatusNotifierItem system tray icon (requires AppIndicator support on GNOME).

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Installation (Recommended)

The easiest and official way to install Mimick on any Linux distribution is via our Flatpak repository. This ensures you receive automatic updates whenever a new version is released.

Run these commands in your terminal:

1. Add the official Mimick repository

flatpak remote-add --user --if-not-exists mimick-repo [https://nicx17.github.io/mimick/mimick.flatpakrepo](https://nicx17.github.io/mimick/mimick.flatpakrepo)

2. Install the application

flatpak install --user mimick-repo io.github.nicx17.mimick

Verify the Flatpak Repo Key

The published Flatpak repository embeds this signing-key fingerprint:

04E2 9556 E951 B2EA 15D3 A8EE 632E 1BC5 D956 579C

You can inspect the currently published key with:

curl -fsSL https://nicx17.github.io/mimick/mimick.flatpakrepo \
  | sed -n 's/^GPGKey=//p' \
  | base64 -d > /tmp/mimick-repo-public.gpg

gpg --show-keys --fingerprint /tmp/mimick-repo-public.gpg

Compare the printed fingerprint to the value above. The email address alone is not the trust anchor; the fingerprint is.

Usage & Configuration

First Launch

Launch Mimick from your Application Launcher. The settings window opens automatically on first launch.

1. Internal URL — LAN address (e.g., http://192.168.1.50:2283).
2. External URL — WAN/Public address (e.g., https://photos.example.com). At least one must be enabled.
3. API Key — Generate in Immich Web UI under Account Settings > API Keys. Needs Asset and Album read/create permissions.
4. Watch Paths — Add folders to monitor with the built-in folder picker. Each folder can be assigned a target Immich album.
5. Run on Startup — Enable this in the Behavior section to start Mimick automatically when you log in.
6. Save & Restart — Applies your settings and relaunches Mimick automatically.
7. Close / Quit — Close hides the settings window and leaves Mimick running; Quit fully exits the app.

Autostart

Use the built-in Run on Startup switch in the settings window.

• Flatpak builds request background/autostart permission through the desktop portal.
• Native builds write an autostart desktop entry to ~/.config/autostart/io.github.nicx17.mimick.desktop.

Folder Access

Mimick now uses selected-folder access instead of full home-directory access in Flatpak.

• Add watch folders from the settings window so the file chooser portal can grant access.
• If you are upgrading from an older build that had full home access, re-add your existing watch folders once so the new permission model can take effect.
• Portal-backed folders may appear by name in the UI and logs instead of showing the raw /run/user/.../doc/... sandbox path.

Existing Files and Album Changes

Mimick does not only sync files created while it is already running.

• On startup, Mimick rescans watched folders and queues media that has not been synced yet.
• A local sync index is used so unchanged files that are already known to be synced are skipped quickly.
• If you change the target Immich album for a watched folder, unchanged files can be reassociated to the new album on the next startup without forcing a full reupload.
• If a previously targeted album was deleted, Mimick refreshes album resolution and recreates or rebinds the target album as needed.

Quitting vs Closing

Mimick is a background app, so closing the settings window does not quit it.

• Use Close in the settings window or the window close button to hide the window and keep Mimick running in the tray.
• Use Quit from the tray menu, the settings window, or the launcher action to stop the app completely.

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Building from Source (For Developers)

If you prefer to compile Mimick yourself, you can build it natively or package it as a local Flatpak.

Prerequisites (Native Build)

• Rust toolchain (cargo): https://rustup.rs
• GTK4 + Libadwaita development headers

Ubuntu / Debian:

sudo apt install libgtk-4-dev libadwaita-1-dev libglib2.0-dev pkg-config build-essential libsecret-1-dev

Fedora:

sudo dnf install gtk4-devel libadwaita-devel libsecret-devel pkg-config

Arch Linux:

sudo pacman -S gtk4 libadwaita libsecret pkgconf base-devel

Native Rust Build

git clone [https://github.com/nicx17/mimick.git](https://github.com/nicx17/mimick.git)
cd mimick
cargo build --release
# Copy the desktop file and icons from setup/ to ~/.local/share/applications and ~/.local/share/icons for launcher integration

# Run Directly
cargo run                   # start in background mode
cargo run -- --settings     # open the settings window immediately

Logs written to the terminal and to ~/.cache/mimick/mimick.log now include timestamps.

Local Flatpak Build

git clone [https://github.com/nicx17/mimick.git](https://github.com/nicx17/mimick.git)
cd mimick
flatpak-builder --user --install --force-clean build-dir io.github.nicx17.mimick.local.yml
flatpak run io.github.nicx17.mimick

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Documentation

• Troubleshooting
• User Guide
• Security Policy

Trust and Verification

Mimick currently publishes a few concrete trust signals:

• signed Flatpak repository metadata
• GitHub release assets with checksums
• CodeQL analysis in GitHub Actions
• CI checks for formatting, linting, tests, and dependency audits

If you install via Flatpak, verify the published signing fingerprint before trusting the repo:

04E2 9556 E951 B2EA 15D3 A8EE 632E 1BC5 D956 579C

Contributing

Pull requests are welcome. See CONTRIBUTING.md for commit and style guidelines.

Acknowledgments

• Application icon illustration by Round Icons on Unsplash.

License

GNU General Public License v3.0 — see LICENSE.