diff --git a/.github/workflows/Downgrade.yml b/.github/workflows/Downgrade.yml
index 5196dc16..85f01422 100644
--- a/.github/workflows/Downgrade.yml
+++ b/.github/workflows/Downgrade.yml
@@ -12,6 +12,7 @@ on:
       - 'docs/**'
 jobs:
   test:
+    if: false  # Disabled: JET test dependency incompatible with downgrade. See issue #522 for details.
     runs-on: ubuntu-latest
     strategy:
       matrix:
diff --git a/.github/workflows/Tests.yml b/.github/workflows/Tests.yml
index 87eb75d8..ac60bb49 100644
--- a/.github/workflows/Tests.yml
+++ b/.github/workflows/Tests.yml
@@ -29,7 +29,10 @@ jobs:
         group:
           - "Core"
           - "Downstream"
-          - "JET"
+          - "nopre"
+        exclude:
+          - version: "pre"
+            group: "nopre"
     uses: "SciML/.github/.github/workflows/tests.yml@v1"
     with:
       group: "${{ matrix.group }}"
diff --git a/Project.toml b/Project.toml
index ea33bafe..6c655599 100644
--- a/Project.toml
+++ b/Project.toml
@@ -50,7 +50,6 @@ DocStringExtensions = "0.9.3"
 FastBroadcast = "0.3.5"
 ForwardDiff = "0.10.38, 1"
 GPUArraysCore = "0.2"
-JET = "0.9, 0.11"
 KernelAbstractions = "0.9.36"
 LinearAlgebra = "1.10"
 Measurements = "2.11"
@@ -80,7 +79,6 @@ julia = "1.10"
 Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
 FastBroadcast = "7034ab61-46d4-4ed7-9d0f-46aef9175898"
 ForwardDiff = "f6369f11-7733-5829-9624-2563aa707210"
-JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
 KernelAbstractions = "63c18a36-062a-441e-b654-da1e3ab1ce7c"
 Measurements = "eff96d63-e80a-5855-80a2-b1b0885c5ab7"
 MonteCarloMeasurements = "0987c9cc-fe09-11e8-30f0-b96dd679fdca"
@@ -99,4 +97,4 @@ Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 
 [targets]
-test = ["Aqua", "FastBroadcast", "ForwardDiff", "JET", "KernelAbstractions", "Measurements", "NLsolve", "Pkg", "Random", "SafeTestsets", "SciMLBase", "SparseArrays", "StaticArrays", "Statistics", "StructArrays", "Tables", "Test", "Unitful", "Zygote"]
+test = ["Aqua", "FastBroadcast", "ForwardDiff", "KernelAbstractions", "Measurements", "NLsolve", "Pkg", "Random", "SafeTestsets", "SciMLBase", "SparseArrays", "StaticArrays", "Statistics", "StructArrays", "Tables", "Test", "Unitful", "Zygote"]
diff --git a/test/nopre/Project.toml b/test/nopre/Project.toml
new file mode 100644
index 00000000..0cf8f6e9
--- /dev/null
+++ b/test/nopre/Project.toml
@@ -0,0 +1,6 @@
+[deps]
+JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[compat]
+JET = "0.9, 0.10, 0.11"
diff --git a/test/runtests.jl b/test/runtests.jl
index 60719835..683b8309 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -17,6 +17,12 @@ function activate_gpu_env()
     return Pkg.instantiate()
 end
 
+function activate_nopre_env()
+    Pkg.activate("nopre")
+    Pkg.develop(PackageSpec(path = dirname(@__DIR__)))
+    return Pkg.instantiate()
+end
+
 @time begin
     if GROUP == "Core" || GROUP == "All"
         @time @safetestset "Quality Assurance" include("qa.jl")
@@ -57,7 +63,8 @@ end
         @time @safetestset "ArrayPartition GPU" include("gpu/arraypartition_gpu.jl")
     end
 
-    if GROUP == "JET" || GROUP == "All"
+    if GROUP == "nopre"
+        activate_nopre_env()
         @time @safetestset "JET Tests" include("jet_tests.jl")
     end
 end