Particle colliders are powered by software, from the simulations supporting their design to the systems controlling the running experiment, and would not be feasible without organizing community efforts into open source projects like Geant4 (simulation of the passage of particles through matter), ROOT (general I/O and analysis toolkit), CVMFS (software deployment) and Indico (event organization) and the python tools of the Scikit-HEP project. However, the numerous libraries have exploded the software stack of new experiments and require often complex dependency management and build tooling. We show how the Spack package manager can adress these problems and make building complex experiment stacks easy and accessible to everyone.