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Fingerprint Reader Expansion Card

The Fingerprint Reader Expansion Card is a community-designed 3D-printed expansion card that houses a Chipsailing CS9711 fingerprint reader inside a Framework expansion card shell1. Designed by theowoo, it integrates an off-the-shelf fingerprint sensor (~11€ from AliExpress) and a USB-A to USB-C adapter (~4€ from eBay), both removed from their original casings and fitted into a custom 3D-printed shell that went through eight CAD iterations1.

The project received positive feedback from Nirav Patel, Framework's CEO1.

Design

The 3D CAD model is based on the printable expansion card drawing officially provided by Framework, forked from the FrameworkComputer/ExpansionCards repository1. Assembly involves removing the external plastic casing from both the fingerprint reader and the USB-A to USB-C adapter — a box cutter and flat-head screwdriver suffice — then fitting the bare PCBs into the printed shell, starting from the sides to avoid damaging electronic components1.

An STL file (ExpansionCard_FingerprintReader.stl) is included for home 3D printing, recommended in black PLA at 0.2 mm layer height with 15% infill1. Framework's README also lists commercial 3D-printing services (Shapeways, Hubs, Treatstock) for those without a printer1.

Linux Support

The CS9711 sensor is not supported by upstream libfprint. Linux support was originally provided through a patched fork, ddlsmurf/libfprint-CS9711, with tested instructions for Fedora 421. That fork was archived on January 3, 2026, and its README now redirects to a new main fork on the ericlinagora/cs9711-driver-cherried-onto-sigfm branch. Support tracking for other distributions is maintained in libfprint issue #610 on freedesktop GitLab2.

Specifications

SpecificationDetails
SensorChipsailing CS9711 fingerprint reader1
Sensor cost~11€ (AliExpress)1
USB adapterUSB-A to USB-C adapter (~4€, eBay)1
Shell3D-printed STL (black PLA, 0.2 mm, 15% infill)1
CAD baseFramework official printable expansion card1
Iterations8 CAD revisions1
LinuxPatched libfprint fork (ddlsmurf/libfprint-CS9711, archived Jan 2026 → new fork on ericlinagora/cs9711-driver-cherried-onto-sigfm), Fedora 421
LicenseCC BY 4.01
Sourcetheowoo/FW-fingerprint-expansion-card (GitHub)1
ProjectDescription
Solokeys Solo2 Expansion Card3D-printed card housing a Solokeys Solo 2 FIDO2 security key
YubiKey Expansion Card AdaptersCommunity adapters for housing YubiKey and Solo 2 keys inside expansion cards

Footnotes

  1. FW-fingerprint-expansion-card — GitHub (theowoo, CC BY 4.0) 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

  2. libfprint issue #610 — CS9711 support — freedesktop GitLab