Indeed, I used the ThingMagic M5e. All the code for the (python) drivers [1] and robot behaviors [2] are open sourced.
Funny story... before (and after) doing higher-level robot behaviors, I worked on low-level reader hardware too (with our mutual colleague, I presume). Most recently, it was building SDRs to interact with super-high datarate passive tags with onboard sensors... to build cyborg dragonflies [3].