diff --git a/.github/workflows/Downgrade.yml b/.github/workflows/Downgrade.yml
index 96bf0df..8218027 100644
--- a/.github/workflows/Downgrade.yml
+++ b/.github/workflows/Downgrade.yml
@@ -16,4 +16,8 @@ jobs:
     uses: "SciML/.github/.github/workflows/downgrade.yml@v1"
     with:
       mode: "deps"
+      # ODEInterface 0.4.8 compiles its Fortran solvers from source via
+      # gfortran in deps/build.jl; without it the build errors with
+      # "Currently only gfortran is supported."
+      apt-packages: "gfortran"
     secrets: "inherit"
diff --git a/.github/workflows/Tests.yml b/.github/workflows/Tests.yml
index c36b34f..462aef6 100644
--- a/.github/workflows/Tests.yml
+++ b/.github/workflows/Tests.yml
@@ -15,4 +15,10 @@ concurrency:
 jobs:
   tests:
     uses: "SciML/.github/.github/workflows/grouped-tests.yml@v1"
+    with:
+      # ODEInterface 0.4.8 builds the Fortran solvers from source via gfortran
+      # in its deps/build.jl; without it the build errors with
+      # "Currently only gfortran is supported." The jll-based 0.5.x path that
+      # needs no gfortran is unusable until ODEInterface 0.5.1 is registered.
+      apt-packages: "gfortran"
     secrets: "inherit"
diff --git a/Project.toml b/Project.toml
index e3f84be..ce69331 100644
--- a/Project.toml
+++ b/Project.toml
@@ -22,7 +22,7 @@ ExplicitImports = "1"
 FunctionWrappers = "1.1.3"
 ModelingToolkit = "9, 10, 11"
 NonlinearSolve = "3, 4"
-ODEInterface = "0.5"
+ODEInterface = "0.4.8"
 ODEProblemLibrary = "1"
 Reexport = "1.2.2"
 SafeTestsets = "0.0.1, 0.1"