diff --git a/config-hlrs/packages.yaml b/config-hlrs/packages.yaml
index 5dbdd22..c84015f 100644
--- a/config-hlrs/packages.yaml
+++ b/config-hlrs/packages.yaml
@@ -2,7 +2,28 @@ packages:
   all:
     compiler: [gcc@12.3.0, aocc@4.1.0]
     providers:
+      mpi: [mpt, openmpi]
       pkgconfig: [pkgconf]
+  openmpi:
+    externals:
+    - spec: openmpi@4.1.6%gcc@=12.3.0~cuda~cxx~cxx_exceptions~java~memchecker+pmi~static~wrapper-rpath
+        fabrics=ucx schedulers=slurm,tm
+      prefix: /opt/hlrs/non-spack/release/23.1.0/mpi/openmpi/4.1.6-gcc-12.3.0
+    - spec: openmpi@4.1.6%aocc@=4.1.0~cuda~cxx~cxx_exceptions~java~memchecker+pmi~static~wrapper-rpath
+        fabrics=ucx schedulers=slurm,tm
+      prefix: /opt/hlrs/non-spack/release/23.1.0/mpi/openmpi/4.1.6-aocc-4.1.0
+    buildable: false
+  mpt:
+    externals:
+      # We have to generate compiler-specific modulefiles in order to
+      # e.g. set custom Fortran modules path. It's hence not possible
+      # to use a single spec based on gcc@8.5.0 although a single spec
+      # would be meaningful due to the _prebuilt_ fashion of MPT.
+    - spec: mpt@2.28%gcc@=12.3.0
+      prefix: /opt/hlrs/non-spack/mpi/mpt/mpt-2.28
+    - spec: mpt@2.28%aocc@=4.1.0
+      prefix: /opt/hlrs/non-spack/mpi/mpt/mpt-2.28
+    buildable: False
   binutils:
     externals:
     - spec: binutils@2.30.123