Used the original Nitrokey HSM model on a code-signing server project with a Customer a couple of years ago. I haven't worked with "big name" HSMs before (we lo

Used the original Nitrokey HSM model on a code-signing server project with a Customer a couple of years ago. I haven't worked with "big name" HSMs before (we looked at Gemalto when we were spec'ing the project but were scared off by the ridiculous pricing) so I can't compare them to "serious" HSMs, but for our project they were a good fit. The applet running inside the original HSM model is in no way free / open source. The dev tools for the applet are really good, the documentation is top notch, and the integration with OpenSC is very good, but it's definitely proprietary. For our purposes that was not problematic. I don't know if this has changed for the "2" model. Edit: The "2" model also uses the proprietary Smartcard HSM applet. It was nice, as compared with big name HSMs, to be able to configure the Nitrokey HSM to support escrow of the key material offline (printed on paper in an AES-encrypted state). The project we were working has a 25 year service life for the key material, and Gemalto's solution was "We can't let you escrow key material but we can let you keep buying new Gemalto HSMs every few years." (I know putting the key material into escrow adds risk, but the risk if keys were lost was considered greater. We ran a commissioning ceremony on the Customer's site, with Customer-provided air-gapped hardware, video recorded and with witnesses present, with the printed keys immediately going into serialized tamper-evident envelopes, all to try to mitigate some of that risk.)