## 1 Introduction  
Over the last two decades, the capabilities and potentials of X-ray computed tomography (CT) and micro-CT has been greatly improved by applying phase-contrast methods, or in general, multi-contrast imaging modalities (phase-contrast, dark-field imaging). This is especially beneficial for biomedical and life science applications, which typically involve low-attenuation-contrast samples that produce very low contrast-to-noise ratio (CNR) images and inferior quality for conventional, attenuation-based CT. In contrast to conventional X-ray CT, phase-contrast techniques rely on detecting small-angle refraction of the X-ray waves traversing the sample and the related phase shifts imparted by the sample [1, 2, 3]. This can be two to three orders of magnitude more sensitive than attenuation contrast in case of soft tissues and bio-samples in the hard X-ray regime. In this way, they extend the capabilities of X-ray imaging to weakly or non-attenuating samples or to those details that lack sufficient visibility in conventional CT. Another interesting modality shedding light on nano-scale structures is X-ray dark field imaging. It relies on ultra-small angle scattering of X-rays in the sample by micro- and nano-scale, typically sub-resolution, structures [4, 5, 6]. Reviews and comparison of X-ray phase-contrast imaging techniques are given in Refs. [3, 7, 8, 9, 10, 11]. Phase-contrast methods were first introduced on synchrotron sources but they found their way relatively fast to laboratory sources. This is due to the developments and availability in micro- and nano-focus X-ray sources and X-ray optical elements such as diffraction gratings. The main techniques used for laboratory X-ray phase-contrast imaging (PCI) include grating-based PCI [12, 10, 13], propagation-based PCI [1, 2, 14], speckle-based PCI [15] and edge illumination [16]. Although there is a plethora of literature regarding phase-retrieval algorithms, especially for propagation-based PCI, access to implementations of those algorithms is relatively limited [17; 18; 19; 20; 21; 22]. Some of the packages work following the conventional pipeline and start with a phase retrieval step on the 2D projection images, which are then back projected using mostly filtered back projection (FBP) or iterative reconstruction methods [18; 19; 22]. It was also shown by [PERSON] and [PERSON] [23] that phase retrieval and reconstruction are interchangeable also when considering approaches other than FBP, such as the Algebraic Reconstruction Technique (ART). Another work compared the conventional pipeline with 3D post-reconstruction phase retrieval, which has definitely benefits when projections images have to be stitched to achieve larger field-of-views (FOVs) at high resolution [20]. Only few packages wrap the phase-retrieval module with other codes for the full 3D tomographic reconstruction pipeline [18; 19; 21; 22], which are available in open source form to the community. These, except for [21], which is a toolbox coupled to the ASTRA package [24], are developed exclusively for imaging at synchrotrons in parallel beam geometry. However, for phase-contrast CT using laboratory-based setup with cone-beam geometry, there is a real lack of open source reconstruction packages. Note that much more open source packages are available for conventional, attenuation-based CT reconstruction. The review of these is beyond the scope of the present paper. Here, we introduce an in-house cone-beam PCI reconstruction package with several options for phase-contrast and dark-field micro-CT reconstruction on laboratory sources. The package enables CT reconstruction for grating-based and propagation-based PCI in cone beam geometries and features a graphical user interface. In the following, we briefly describe which methods and how are implemented in the package. After that, we will give representative examples demonstrating how the package works (see Figures 1-3). Note that the goal of the paper is not to perform a benchmark of our package against others.