# Difference between mpas-bundle and spack-stack **URL:** \ **Category:** JEDI\ **Created:** [October 30, 2024, 12:47am UTC](https://forums.jcsda.org/t/difference-between-mpas-bundle-and-spack-stack/632 "2024-10-30T00:47:12Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![bigveech](https://avatars.discourse-cdn.com/v4/letter/b/bbe5ce/32.png) [@bigveech](https://forums.jcsda.org/u/bigveech)\ **Post date:** [October 30, 2024, 12:47am UTC](https://forums.jcsda.org/t/difference-between-mpas-bundle-and-spack-stack/632/1 "2024-10-30T00:47:12Z")
Hello everyone, I’m attempting to do some data assimilation with using JEDI MPAS. I started by looking at this repo GitHub `mpas-jedi` which suggested that I use [mpas-bundle](https://github.com/JCSDA/mpas-bundle). After attempting to build, I came across another repo [spack-stack](https://github.com/JCSDA/spack-stack) which also looks like it bundles MPAS. Which of these should I focus on building? Also, I’ve been building `mpas-bundle` version 3.0.1. Is that the most widely used version? It seems like the last “release” was 1.0.0. Thanks! ---
**Author:** ![steven.vahl](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.jcsda.org/steven.vahl/32/223_2.png) [@steven.vahl](https://forums.jcsda.org/u/steven.vahl)\ **Post date:** [October 30, 2024, 2:56pm UTC](https://forums.jcsda.org/t/difference-between-mpas-bundle-and-spack-stack/632/2 "2024-10-30T14:56:42Z")
spack-stack and mpas-bundle are not really building the same thing. spack-stack builds and creates modules for all the prerequisite packages that are required in order to build all the JEDI repositories. If you are working on an HPC, there is a good chance that spack-stack is already installed on it. See the “Preconfigured Sites” list here: [Table of contents — spack-stack develop documentation](https://spack-stack.readthedocs.io/en/latest/index.html) If you are working on a PC, then you need to build spack-stack locally first, following the instructions in the “Generating new site configs” section of the above link. This is a time-consuming process, and the instructions must be followed carefully. If you have access to an HPC, it might be simpler to use that with the pre-installed spack-stack. Once you have your spack-stack environment in place, you are ready to build a JEDI bundle. The JCSDA supports a bundle called jedi-bundle. You can find instructions on how to build it here: [https://jointcenterforsatellitedataassimilation-jedi-docs.readthedocs-hosted.com/en/latest/using/building\_and\_running/building\_jedi.html](https://jointcenterforsatellitedataassimilation-jedi-docs.readthedocs-hosted.com/en/latest/using/building_and_running/building_jedi.html) jedi-bundle builds everything needed by mpas-jedi, fv3-jedi, and soca, and so builds everything you need, but also builds things you do not need if you’re just working with mpas-jedi. Which brings us to mpas-bundle. mpas-bundle serves the same purpose as jedi-bundle, but leaves out the JEDI repositories that are not needed for building and running mpas-jedi. So the build might be a little faster and lighter. mpas-bundle is not supported by the JCSDA, and is (or is not) maintained by NCAR/MMM. I don’t know its current maintenance status. Depending on your level of CMAKE expertise, you can modify the main CMakeLists.txt file in jedi-bundle to comment-out the repositories that are not needed by mpas-jedi. Or you can just build the whole thing if you don’t mind building extra repositories. ---
**Author:** ![Astrogirlanajli](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.jcsda.org/astrogirlanajli/32/273_2.png) [@Astrogirlanajli](https://forums.jcsda.org/u/Astrogirlanajli)\ **Post date:** [February 24, 2026, 9:09am UTC](https://forums.jcsda.org/t/difference-between-mpas-bundle-and-spack-stack/632/3 "2026-02-24T09:09:44Z")
Hi, I have a follow-up question. After successfully building the jedi-bundle (here, in my case, on Ubuntu), how do I run or access MPAS-JEDI? - Thank you.