hack2you keyboard with a BlackBerry 9900 optical trackpad
lululvlv's replacement keyboard puts a BlackBerry 9900 optical trackpad where the ball was and runs ZMK; sold on Tindie and hack2you.tech since late 2025.
What it takes
- Disassembly
- Purchase required
Difficulty 2 of 3 — moderate.
Details
Announced by lululvlv (hack2you, also behind the LULU cool pad and the DIY NVMe modules) in December 2025: a drop-in keyboard with a BB9900 optical trackpad in place of the trackball, offered as a one-piece 6061 aluminium model A or a two-piece model B in black, blue or silver, with a v2.0 keyboard that cuts actuation force by about a third. Firmware is ZMK (Bill-lulu/uc9900, built on ZitaoTech's work) and compiles to a .uf2 through GitHub Actions.
Owners like fane call the trackpad a big step up from the ball; early Fn-layer and right-modifier bugs were fixed in firmware v1.2 and more thoroughly in thoughtfix's fix9900 fork (trackpad click toggles scroll mode, volume keys and Right Alt/Ctrl fixed). 413ZERO published a CNC front-cover STEP with an enlarged opening for the kit — see the Enclosure category.
Links
Open at Forum threadRelated mods
Open-source QMK port of the keyboard firmware: Select + ball scrolls, Fn + G game mode, precision mode, tap-hold keys and a web tester, flashed over USB.
ClockworkPi's flash tool updates the keyboard's STM32 over the internal USB with dfu-util, no disassembly; the UART route and the S1 pads recover a bricked one.
The 0.1 mm diffuser film dims the backlight; pulling it out brightens the keys, and beams' printed 95A TPU diffuser evens the light and lightens the key feel.
A modified build of ClockworkPi's own Arduino firmware: QMK-like trackball smoothing and Select + ball scrolling without QMK's USB power quirks.
A clean rewrite of the stock keyboard firmware on STM32 HAL: ten switchable layers, a better trackball curve with inertia, Fn lock and auto-dimming backlight.
Bismuth replaced the trackball with a 23 mm Cirque Glidepoint pad driven by a QT Py RP2040 over I²C, which shows up as a plain USB mouse with no driver work.