  The idea of post-measurement coincidence pairing simplifies substantially
long-distance, repeater-like quantum key distribution (QKD) by eliminating the
need for tracking the differential phase of the users' lasers. However, optical
frequency tracking remains necessary and can become a severe burden in future
deployment of multi-node quantum networks. Here, we resolve this problem by
referencing each user's laser to an absolute frequency standard and demonstrate
a practical post-measurement pairing QKD with excellent long-term stability. We
confirm the setup's repeater-like behavior and achieve a finite-size secure key
rate (SKR) of 15.94 bit/s over 504 km fiber, which overcomes the absolute
repeaterless bound by 1.28 times. Over a fiber length 100 km, the setup
delivers an impressive SKR of 285.68 kbit/s. Our work paves the way towards an
efficient muti-user quantum network with the local frequency standard.
