Measurements of the CKM angle $\gamma$ at LHCb

The angle $\gamma$ is the only complex phase of the Cabibbo-Kobayashi- Maskawa (CKM) matrix that can be measured at tree level. It therefore establishes a benchmark of the Standard Model (SM) against which loop-level measurements of the CKM parameters can be tested in order to reveal the presence of new physics. The LHCb experiment can determine $\gamma$ from the analysis of both time-integrated and differential decay rates of $B$ to $D$ mesons. The combination of LHCb measurements represents the most precise determination of $\gamma$ as of today and is going to reach the sub degree level of precision for a single measurement with the upgrade of the experiment.