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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 ↩