The paper presents a method for measuring fermion parity in indium arsenide-aluminum (InAs-Al) hybrid devices using a single-shot interferometric technique. The measurement is performed on a gate-defined nanowire that is tunnel-coupled to quantum dots, causing a state-dependent shift in the quantum capacitance of up to 1 farad. The interferometer is designed to detect flux $h/2e$-periodic bimodality with a signal-to-noise ratio of 1 in 3.7 μs at optimal flux values. The measured time traces show dwell times in the two associated states exceeding 1 ms at in-plane magnetic fields of approximately 2 T. These results are consistent with measuring the fermion parity of Majorana zero modes separated by about 3 μm, with a low rate of quasiparticle poisoning. The large capacitance shift and long poisoning time enable a parity measurement error probability of 1%. The paper also discusses the device design, fabrication, and system setup, as well as the interpretation of the observed phenomena, including the impact of quasiparticle injection and the analysis of different interferometry regimes.The paper presents a method for measuring fermion parity in indium arsenide-aluminum (InAs-Al) hybrid devices using a single-shot interferometric technique. The measurement is performed on a gate-defined nanowire that is tunnel-coupled to quantum dots, causing a state-dependent shift in the quantum capacitance of up to 1 farad. The interferometer is designed to detect flux $h/2e$-periodic bimodality with a signal-to-noise ratio of 1 in 3.7 μs at optimal flux values. The measured time traces show dwell times in the two associated states exceeding 1 ms at in-plane magnetic fields of approximately 2 T. These results are consistent with measuring the fermion parity of Majorana zero modes separated by about 3 μm, with a low rate of quasiparticle poisoning. The large capacitance shift and long poisoning time enable a parity measurement error probability of 1%. The paper also discusses the device design, fabrication, and system setup, as well as the interpretation of the observed phenomena, including the impact of quasiparticle injection and the analysis of different interferometry regimes.