Naughty Keyboard

Naughty Keyboard is a tool for testers and developers. One shortcut types the next awkward value into the field in front of you: null, a trailing space, a zero-width space, 30.02.2026, =1+1, a name of 65 535 characters. They are the values real users and real data produce, and a form you only ever tried with "John Smith" has never met them.

Every value comes with what it usually breaks and what a correct application does instead. When one of them breaks something, one more shortcut copies a report block you can paste straight into a ticket. A window and a command line, over one engine.

What it can do

One shortcut, one value - Alt+Shift+N clears the line and types the next value of the current pack into whatever window has the keyboard. Previous and restart are one chord away, and every chord can be changed. Values that explain themselves - each one carries breaks (what it usually breaks, and why) and expect (what a correct application does). The pack file, nkb show and the report block all say so. Invisible characters made visible - the palette draws one as a marker, ␣, instead of showing nothing, and counts every value four ways: graphemes, code points, bytes and UTF-16 units. Know where you are - the palette shows the value that comes next and a counter of how far through the pack you are, and the value window searches the values of every pack at once. A bug report in one chord - Alt+Shift+B copies a block for the last value: which value, from which version of the pack, typed as what, how large, and whether all of it arrived. The value is written in a form someone else can type back, never as the marker the palette drew. Never takes the keyboard - the palette is a display driven by shortcuts and does not take focus, so the cursor never leaves the field you are testing. Clipboard mode - put values on the clipboard to paste yourself, for one window or for all of them. Packs you can check - a pack is a plain TOML file, nkb lint checks it against the format rules, nkb fmt puts it in canonical shape, and nkb new-pack writes the skeleton. Made for scripts too - nkb emit prints a pack as JSON, CSV or one value per line, escaped or raw, optionally as base64. Every command has exit codes you can branch on. Offline, free, no telemetry - GPL-3.0, no account, and it opens no network connection.