RapidFireKeys

Hold a key, and RapidFireKeys presses it for you — over and over, only in the apps you choose.

A small Windows tray app built for Diablo II: Resurrected. In D2R, holding a skill key while your cursor is over an item or object stops the skill from casting, so you end up button-mashing to keep it going. RapidFireKeys does the mashing: hold the key down and it keeps firing until you let go.

Download

Download RapidFireKeys.exe (latest release, 69 MB)

Put RapidFireKeys.exe in a folder of its own and run it. That is the whole installation: it is a single self-contained file with the .NET runtime built in, so nothing else needs to be installed. Settings live in %AppData%\RapidFireKeys; delete that folder and the exe to remove it completely. You need 64-bit Windows.

Windows SmartScreen will warn that the app is unsigned. Choose More info then Run anyway, or read the source and build it yourself. A .sha256 is published beside each release so you can confirm you have the file the release workflow built.

Windows will also show a UAC prompt every time it starts. RapidFireKeys always runs as administrator, because Windows blocks simulated key presses from a normal app to an app running elevated — and games often run elevated. If you would rather not confirm UAC on every launch, create a Task Scheduler task for RapidFireKeys.exe with Run with highest privileges ticked and launch the app from that task (for example with a shortcut to schtasks /run /tn RapidFireKeys).

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If it saves your fingers some button-mashing

RapidFireKeys is free and open source, and will stay that way — no paid version, no nag screens, nothing held back.

If it has earned a place in your tray, you can put something toward keeping it working after the next game patch.

Not at all expected. Starring the repo, or pointing a friend at it, helps just as much.

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Getting started

1. Run RapidFireKeys.exe and accept the UAC prompt. A flame icon appears in the system tray.
2. That's it for D2R: it comes set up for D2R.exe with the usual skill keys (see the defaults). Start the game, hold a skill key, and it keeps casting.
3. To change anything, double-click the tray icon (or right-click it and choose Settings...).

RapidFireKeys only does anything while one of your configured apps is the window in front. Everywhere else your keys behave normally.

What it does

You choose the apps and the keys

The Settings window lists the apps on the left and that app's hotkeys on the right.

• Add app... offers the programs running right now, or you can type an .exe name. Use it for any game with the same hold-to-repeat problem.
• Add hotkey... asks you to press the key, or click the mouse button, you want rapid-fired. Hold Shift, Ctrl or Alt at the same time and the hotkey will only rapid-fire while that modifier is held too.
• Every hotkey can be changed in place: pick a different key from the list, or tick Needs Shift / Needs Ctrl / Needs Alt.
• Restore defaults puts back the original D2R setup.
• Import... / Export... move your setup to and from a file (see Your settings).

Nothing changes until you press Save, and saving takes effect immediately — no restart. Cancel discards everything since the window opened. A key that is held at the moment you remove it stops firing.

Supported keys are the mouse buttons (left, right, middle, back, forward), letters, the number row, the numpad, F1–F12, arrows, Space, Enter, Tab, Backspace, Escape, Insert/Delete/Home/End/Page Up/Page Down, and Shift, Ctrl and Alt themselves. Not every key has been tested in every game.

Light or dark, following Windows

Every window and the tray menu come in light and dark. By default RapidFireKeys follows Windows' own app setting (Settings → Personalization → Colors), and switches along with it while running. Theme in Settings can pin it to Light or Dark instead; the choice previews immediately and Cancel puts it back.

It only fires keys you are physically holding

RapidFireKeys watches your real keyboard and mouse and ignores input sent by other software, so automation tools or macros cannot set it off. Rapid-fire stops as soon as you let go, release a required modifier, or switch to a different window — even another copy of the same game.

%AppData%\RapidFireKeys\RapidFireKeys.log records when each rapid-fire starts and stops, which helps track down a misfire.

It keeps itself up to date

Once a day RapidFireKeys checks whether a newer version has been published. When one has, a notification pops up from the tray icon and Update to … appears at the top of the tray menu. Click either to see what changed; press Update now and it downloads the new exe, checks it against the checksum GitHub recorded for it, swaps it in and restarts — still elevated, with no second UAC prompt. Your settings are kept.

A failed update costs nothing but the download: nothing is replaced until the new file has been fully downloaded and verified, and a download that does not match its checksum is discarded. Nothing is ever installed without you pressing the button.

Check for Updates in the tray menu (or Check now in Settings) asks on demand, and the daily check can be turned off in Settings. It sends no identifier and nothing about your machine, apps or hotkeys — it is a plain request for a public file.

Automatic updates start with 1.1.0. If you are on 1.0.5 or earlier, download 1.1.0 by hand once and replace your old exe; your CONFIG.json is imported.

The defaults

Out of the box, RapidFireKeys rapid-fires these in D2R.exe:

Key	Fires when
Left mouse button	held with Shift (so ordinary clicking and walking are unaffected)
Right, middle, back and forward mouse buttons	held
Backspace, Q, W, E, R, A, S, D, F, G, H, B	held

Your settings, and moving them

Everything RapidFireKeys remembers — apps, hotkeys, theme, the update check — is in one file, %AppData%\RapidFireKeys\settings.json, beside its log. The Settings window is the place to change it.

• Export... saves what is on screen to a file of your choosing: a backup, or a way to take your setup to another PC.
• Import... loads an exported file into the window. It also accepts a CONFIG.json from RapidFireKeys 1.0.x. As with any other change, nothing is kept until you press Save, and Cancel discards it.

Upgrading from 1.0.x? On first run, 1.1.0 imports the CONFIG.json next to the exe automatically. That file is left where it is but no longer used.

Removing it

Choose Exit from the tray menu, delete RapidFireKeys.exe, and delete %AppData%\RapidFireKeys if you don't want to keep your settings. Nothing was installed anywhere else: no registry entries, no services, no startup items.

A word of warning

Some online games detect "auto presses" and ban players for macroing. Whether this is detectable is unknown. It has been used for a long time online in Diablo II: Resurrected without issues, but there is no guarantee Blizzard or anyone else won't decide otherwise. Use it at your own risk.

The Support menu item

Release builds carry a ♥ Support RapidFireKeys item in the tray menu and a button in Settings; a build from a clean checkout does not. The destination is a build property, empty in this repository, and with nothing set the item does not appear at all — so a fork ships no ask, and there is nothing to remember to strip out.

Building from source

Needs the .NET 8 SDK.

dotnet build RapidFireKeys\RapidFireKeys.sln -c Release
dotnet test  RapidFireKeys\RapidFireKeys.sln -c Release   # 106 tests

The tests cover the parts that fail quietly rather than loudly: reading hand-written configs, writing back exactly what Settings showed, whether a published version is newer than the one running, and whether a download matches its checksum.

To build the release exe — self-contained, single file:

.\publish.ps1
.\publish.ps1 -SponsorUrl "https://github.com/sponsors/<user>?frequency=one-time&amount={amount}"

publish.ps1 runs the tests first and refuses to publish if any fail. An {amount} placeholder turns the support dialog into a picker — $3 / $5 / $10 / $25 or another whole amount — with the chosen sum substituted into the link.

Releases themselves are built by GitHub Actions: pushing a v* tag checks that the tag matches <Version> in the csproj, runs the tests, publishes the exe with a SHA-256 beside it, and opens a draft release to look over before anyone can download it (or be offered it by the updater).

How it is put together

RapidFireKeys\
├── RapidFireKeys\
│   ├── Form1.cs              Tray icon, menu, and the loop that watches held keys
│   ├── PhysicalInput.cs      Low-level hooks: which keys are physically held
│   ├── HotkeyConfig.cs       Reads and compiles hotkey lists
│   ├── Preferences.cs        The settings file in %AppData%, import/export, 1.0.x migration
│   ├── Theme.cs              Light/dark colors for every window and the tray menu
│   ├── SponsorLink.cs        Where the support button goes, if anywhere
│   ├── Views\
│   │   ├── SettingsForm.cs   Apps and hotkeys editor
│   │   ├── CaptureKeyForm.cs "Press the key to rapid-fire"
│   │   ├── AddAppForm.cs     Pick a running program or type an .exe
│   │   ├── UpdateForm.cs     Release notes and Update now
│   │   └── SponsorForm.cs    The support dialog
│   └── Updates\
│       ├── UpdateService.cs  Reads the releases feed
│       ├── UpdateInstaller.cs Downloads, verifies and swaps in the new exe
│       └── ...               Version comparison, schedule, release notes
└── RapidFireKeys.Tests\

The core is one loop: every 10 ms it checks which app is in front, and for each of that app's hotkeys whether the key is held. A key counts as held only when Windows reports it down and the low-level hooks in PhysicalInput saw a physical press, which is what keeps keys sent by other software from setting it off. Once a key has been held for about 200 ms it is re-sent every 50 ms, half down and half up, posted straight to the foreground window, until it is released, its modifier is let go, or the window changes.

Hotkeys reach that loop as one compiled snapshot that Settings swaps in whole on Save, so the loop never sees half of an edit.

Version history

See CHANGELOG.md.

Third-party components

Component	License	Used for
.NET 8 / Windows Forms	MIT	the app itself, bundled into the single exe
xUnit	Apache 2.0	tests only
Shouldly	BSD-3-Clause	tests only

Diablo II: Resurrected is a trademark of Blizzard Entertainment. This is an unofficial tool and is not affiliated with or endorsed by Blizzard.