Abstract: In this talk I will introduce quantum computing and explain the need for quantum error correction---the process by which we detect and account for errors in a quantum computer.  The decoder is a central element of this process.  It is the decoder’s job to infer the quantum errors that occurred from the indirect measurements we can make---a job that must be done as accurately as possible at MHz frequency.  I will explain the main challenges that need to be overcome to build such decoders, and introduce some of our recent results boosting the accuracy of the system by better modelling and engineering the errors that occur.