WaveletsExt.jl: Extending the boundaries of wavelets in Julia. Whether it is seismic surveys, ECG signals, stock market trends, or sensor data, the wavelet and wavelet packet transforms are powerful tools for signal analysis and classi cation with many advantages over the conventional Fourier methods. Primary among them is the ability to extract information localized in both time and frequency domains, enabling multiresolution analysis (Daubechies, 1992; Mallat, 2009). As such, wavelets and wavelet packets have become popular tools for computational harmonic analysis. WaveletsExt.jl was developed to augment Wavelets.jl (the existing wavelet toolbox for Julia) by providing routines for wavelet analysis, wavelet packet analysis, and associated utilities