“…Addressing these challenges, I have developed , a Python-based package that acts as a comprehensive repository for various biomarkers of aging and aging clocks. offers: (i) a Python-centric approach, utilizing the versatile AnnData ( Virshup et al 2021 ) format of annotated data matrices in memory and on disk; (ii) an expanding repository, currently encompassing over 50 clocks with routine updates given new developments in the literature; (iii) clocks based on a diverse range of data types, encompassing DNA methylation ( Hannum et al 2013 , Horvath 2013 , Knight et al 2016 , Lin et al 2016 , Petkovich et al 2017 , Stubbs et al 2017 , Zhang et al 2017 , Horvath et al 2018 , Levine et al 2018 , Meer et al 2018 , Thompson et al 2018 , Lee et al 2019 , Lu et al 2019 , Zhang et al 2019 , Han et al 2020 , McEwen et al 2020 , Belsky et al 2022 , de Lima Camillo et al 2022 , Endicott et al 2022 , Higgins-Chen et al 2022 , Lu et al 2022 , Dec et al 2023 , Li et al 2023 , Lu et al 2023 , McGreevy et al 2023 , Ying et al 2024 ), transcriptomics ( Meyer and Schumacher 2021 ), histone mark ChIP-Seq ( de Lima Camillo et al 2023 ), and ATAC-Seq ( Morandini et al 2024 ); (iv) a variety of models, including linear, principal component (PC) linear models, neural networks, and automatic relevance determination (ARD) ( MacKay 2003 ) models; (v) a PyTorch-based ( Paszke et al 2019 ) backend that leverages GPU processing for enhanced inference speeds; (vi) a multi-species scope, currently covering H.sapiens , M.musculus , C.elegans , and various mammalian species.…”