Code and processed data accompanying the Seismological Research Letters article "Calibrating Microwave-Frequency Fiber Interferometry against Co-located DAS: Earthquakes, Ocean Waves, and Traffic" (Wang et al., 2026). During the 2024 Kefalonia (Greece) experiment, a 15.3 km terrestrial–submarine telecommunication cable was co-instrumented with Microwave-Frequency Fiber Interferometry (MFFI) and a co-located Silixa iDAS Distributed Acoustic Sensing (DAS) interrogator from 2024-04-24 to 2024-06-23. The study calibrates the MFFI sensor against DAS across three signal regimes: the ocean-wave (microseism) band 0.1–0.4 Hz, regional and local earthquakes at 1–12 Hz, and localized vehicle (traffic) signals at 1–12 Hz. Contents. Nine production figure scripts reproducing every paper figure (copied verbatim from the manuscript workflow); vendored custom Python modules (pydas_readers, das_mffi_io, load_das_h5_PE2024, plot, load_kefa_meteo, noa); processed and intermediate datasets (event and matched-filter template catalogs, daily MFFI 80 Hz time series, daily power-spectral-density products, Copernicus/ERA5 wind and significant-wave-height data, and a cached NOA FDSN station inventory); three small raw DAS waveform slices for the showcased earthquake and vehicle events, preserved in the original HDF5 schema so the scripts consume them unchanged; and the publication-ready figures. The full ~8.8 TB raw DAS catalogue is referenced externally rather than deposited — see data/raw_pointers/RAW_DATA_README.md for the institutional contact and access procedure. Licensing. The code is released under BSD-3-Clause (LICENSE-CODE); the data, figures, and documentation are released under CC-BY-4.0 (LICENSE-DATA).