Car Manager — How to use

A guide for using the Car Manager desktop app. (Building and running from source is covered by the developer README.md in the repository.)

Current version tracks your cars, their maintenance and incident history, mileage readings, a mileage-over-time chart, and maintenance schedules that tell you when each service is next due.

Installing

Download the installer for your system from the download page, then run it. Both installers ask the same three things and neither needs administrator rights — Car Manager installs for your user account only.

1. Accept the license. Car Manager is free to use — for yourself, or for your business's own vehicles. You may not resell it or offer it as a rival product.
2. Choose where the program goes. Your cars and history are not stored there — the installer shows you the separate folder they live in (see Where your data lives below), which is kept when you uninstall.
3. Finish. You can create a desktop shortcut and launch the app straight away. Car Manager is added to your applications menu either way.

On Windows the first run of the installer shows a “Windows protected your PC” warning, because these installers are not code-signed: click More info, then Run anyway. On Linux, mark the downloaded file executable (chmod +x) first.

To uninstall, use Apps & features on Windows or the Uninstall Car Manager entry in your applications menu on Linux. It asks whether to keep your cars and maintenance history, and keeping them is the preselected answer.

There is also a portable AppImage for Linux: a single file you run from anywhere, with no installer and no menu entry. It stores its data in the same place, so you can switch between the two.

Opening the app

Launch Car Manager from your applications (or, from source, make run). It opens on the Dashboard. The sidebar has five sections: Dashboard, Cars, Maintenance, Mileage, and Administration.

At the bottom of the sidebar, Help opens this guide in your web browser. If no browser can be opened, the address is shown underneath so you can type it in yourself.

Adding a car

1. On the Cars page, click Add car (top right of Your cars). A window opens; fill in:
   • Brand and Model (required) — e.g. Toyota, Corolla.
   • Year — the model year.
   • License plate (optional).
   • Current mileage (optional) — the odometer reading today; this seeds the car's first mileage reading.
   • First registered on (optional) — the car's first-registration date (its première mise en circulation).
   • Notes (optional) — any free-text details you want to keep about the car.
2. Click Add car. The window closes and the car appears in Your cars.

If something is missing (e.g. no brand), the form shows a short message and nothing is saved — just fill it in and try again. Cancel (or pressing Esc) closes the window without saving anything.

Viewing your cars

Your cars lists every vehicle with its brand, model, year, plate, and current mileage (a dash — means no value was recorded yet). Current mileage always reflects the most recent maintenance record, incident, or mileage reading you've logged — whichever happened last.

Editing or deleting a car

Click Edit on the car's row to reopen the same window with its details filled in; change what you need and click Save changes. Mileage isn't editable here — it's worked out from the records you log, so correct it on the Mileage page instead.

To remove a car, click Edit, then Delete car…. Deleting a car also deletes all of its maintenance records, mileage readings, incidents and schedules, and this cannot be undone — so you're asked to type the car's name (e.g. Toyota Corolla) before the Delete car button unlocks. If you want a copy of the data first, export a backup from the Administration page.

Recording maintenance and incidents

On the Maintenance page, pick a car from the selector at the top (if you only have one car, it's selected automatically).

• Add a maintenance record: a record is one visit — one date, one odometer reading, and one or more operations performed. Under Operations, pick a task (e.g. Engine oil change) from the dropdown; click Add operation to record more tasks done in the same visit (e.g. add Brake fluid replacement) and Remove to drop one. Then pick the date and odometer reading, optionally add a cost and notes, and click Add maintenance record — at least one operation is required. It appears in Maintenance history below, which lists all the visit's operations together. The operation dropdowns are filled from the label catalog you manage on the Administration page (see below); the same task can't be added twice to one visit. Each operation you record also advances any matching maintenance schedule for that car.
• Log an incident or repair: for one-off issues that aren't part of a regular service (a flat tire, a windshield crack), fill in a description, date, mileage, and optionally cost/notes, then click Log incident / repair. It appears in Incidents & repairs below.
• Edit or delete: click Edit on any row to load it back into the form above with a Save changes button (and Cancel to back out without saving), or click Delete to remove it immediately.
• Mileage is checked against the readings recorded just before and just after the date you enter (across maintenance, incidents, and mileage readings alike) — it must sit between them. A value outside that range is rejected with an error, so you can't accidentally log the odometer going backwards. Backfilling an older event still works as long as the mileage fits between its neighbors in time.

Knowing when a service is next due (schedules)

On the Maintenance page, above the service history, the Next due section lets you set up recurring services for the selected car:

• Add a schedule: pick an operation (from the same label catalog), then enter how often it repeats — every N km, every N months, or both. At least one is required. When you set both, the service counts as due whenever the first of the two is reached.
• Each schedule shows a colored status based on your car's real history: green (on track), orange (due soon — within 1,000 km or one month), or red (overdue). The text tells you how much is left, e.g. "Due in 800 km" or "Overdue by 2 months".
• You don't reset anything by hand: when you record a maintenance entry for that operation, the schedule automatically counts from that visit. Until a job has ever been logged, it counts from the car's earliest reading.
• Edit or Delete a schedule with the buttons on its row. Each car can have one schedule per operation.
• The list is ordered by urgency: anything overdue comes first, then whatever is closest to being due. The job to do next is always at the top.

The Dashboard rolls this up across all your cars — a count of how many services are due soon or overdue, with the most urgent ones listed.

Tracking mileage

On the Mileage page, pick a car and you'll see:

• A line chart of mileage over time, built from every maintenance record, incident, and standalone mileage reading you've logged for that car — not just dedicated mileage entries. Overlaid on the same chart, a bar per calendar year shows the distance driven that year (labeled with its km value on top of the bar).
• A form to log a mileage reading — just an odometer check with no maintenance involved, useful for keeping the chart populated between service visits.
• A list of your mileage readings, with the same Edit/Delete actions as the Maintenance page.

Managing maintenance labels (Administration)

The Administration page manages the catalog of maintenance task labels — the values that appear in the Label dropdown when you record maintenance. The catalog comes pre-filled with 30 common tasks (engine oil change, brake pads replacement, timing belt replacement, and so on) the first time you launch the app, so you can start recording maintenance right away.

• Add a label: type a name in Add label and click Add label. It appears in the list and becomes available in the maintenance dropdown.
• Rename a label: click Edit on a row, change the name, and click Save (or Cancel to back out). Renaming updates every maintenance record that already uses that label — the history stays consistent.
• Delete a label: click Delete. A label that isn't used by any maintenance record or schedule is removed immediately. A label that is in use can't be deleted (that would orphan history or a schedule) — you'll see a short message explaining why, and nothing is removed.
• Label names must be unique. Adding or renaming to a name that already exists (ignoring upper/lower case) is rejected with a message.

Backing up and restoring your data (Administration)

The Administration page has a Backup & restore panel that saves or restores everything — your label catalog and all your cars with their maintenance visits, mileage readings, incidents and schedules — as a single .json file.

• Export all data…: click it, choose where to save the file. Keep this file somewhere safe, or copy it to another computer to move your data across. The backup is a plain, unencrypted .json file — store it somewhere you trust.
• Import (replaces all data)…: click it and confirm the warning, then pick a backup file. Importing replaces everything currently in the app with the contents of that file, so use it to restore a backup or load your data onto a new machine — not to merge two sets of data. If the file is damaged or was made by an incompatible version, the import is rejected and your current data is left untouched. On success the page refreshes to show the restored data.

Where your data lives

Everything is stored locally on your computer, in a single database file:

System	Location
Windows	%LOCALAPPDATA%\CarManagerData\carmanager.db
Linux	~/.local/share/CarManager/carmanager.db

Nothing is sent anywhere — the app works fully offline. That folder is separate from the program, so it is untouched by updates, and uninstalling keeps it unless you say otherwise (the uninstaller asks, and keeping is preselected). Both installers show you this path before installing and again when they finish.

If you are upgrading from an earlier version on Windows, your database used to sit in the same folder as the program; the app moves it to the location above by itself, the first time you start it.

For a portable copy you can move or archive, use the Backup & restore panel above rather than copying the database file directly — and a backup is still worth having before any uninstall, since nothing protects that folder from being deleted by hand.