diff --git a/.github/workflows/changelog-enforcer.yml b/.github/workflows/changelog-enforcer.yml
index bfc33ef..2dbb0fd 100644
--- a/.github/workflows/changelog-enforcer.yml
+++ b/.github/workflows/changelog-enforcer.yml
@@ -10,6 +10,7 @@ on:
 jobs:
   # Enforces the update of a changelog file on every pull request 
   changelog:
+    if: github.actor != 'dependabot[bot]'
     runs-on: ubuntu-latest
     steps:
     - uses: dangoslen/changelog-enforcer@v3
diff --git a/.github/workflows/ci-julia-nightly.yml b/.github/workflows/ci-julia-nightly.yml
index 35ec0c0..fca6a6e 100644
--- a/.github/workflows/ci-julia-nightly.yml
+++ b/.github/workflows/ci-julia-nightly.yml
@@ -16,7 +16,7 @@ env:
   PYTHON: ~
 jobs:
   test:
-    name: Julia ${{ matrix.version }} - t=${{ matrix.threads }} - jet=${{ matrix.jet }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
+    name: Julia ${{ matrix.version }} - t=${{ matrix.threads }} - tests=${{ matrix.test_args }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
@@ -26,12 +26,12 @@ jobs:
             arch: x64
             version: alpha
             threads: 2
-            jet: 'false'
+            test_args: general
           - os: ubuntu-latest
             arch: x64
             version: '1'
             threads: 2
-            jet: 'true'
+            test_args: jet
     steps:
       - uses: actions/checkout@v7
       - uses: julia-actions/install-juliaup@v3
@@ -40,9 +40,10 @@ jobs:
       - uses: julia-actions/cache@v3
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
+        with:
+          test_args: ${{ matrix.test_args }}
         env:
           JULIA_NUM_THREADS: ${{ matrix.threads }}
-          JET_TEST: ${{ matrix.jet }}
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v7
         with:
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5b1fe46..3768fbd 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,10 +36,6 @@ jobs:
             os: macos-latest
             version: '1'
             threads: '1'
-          - arch: x64
-            os: windows-latest
-            version: '1'
-            threads: '1'
     steps:
       - uses: actions/checkout@v7
       - uses: julia-actions/setup-julia@v3
@@ -50,6 +46,8 @@ jobs:
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
         env:
+          # Avoid parallel-GC crashes in the GAP/Oscar-backed Tanner tests.
+          JULIA_NUM_GC_THREADS: '1'
           JULIA_NUM_THREADS: ${{ matrix.threads }}
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v7
@@ -58,6 +56,7 @@ jobs:
           token: ${{ secrets.CODECOV_TOKEN }}
   docs:
     name: Documentation
+    if: github.actor != 'dependabot[bot]'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v7
diff --git a/.github/workflows/downgrade.yml b/.github/workflows/downgrade.yml
index bd56edd..ab5e902 100644
--- a/.github/workflows/downgrade.yml
+++ b/.github/workflows/downgrade.yml
@@ -21,10 +21,26 @@ jobs:
       - uses: julia-actions/setup-julia@v3
         with:
           version: ${{ matrix.version }}
+      - name: Disable workspace directives for downgrade run
+        run: |
+          julia --color=yes -e '
+            using TOML
+            project = TOML.parsefile("Project.toml")
+            if haskey(project, "workspace")
+              delete!(project, "workspace")
+              open("Project.toml", "w") do io
+                TOML.print(io, project)
+              end
+            end
+          '
       - uses: julia-actions/julia-downgrade-compat@v2
         with:
-          skip: Pkg,TOML,InteractiveUtils,Random,LinearAlgebra
+          skip: Pkg,TOML,InteractiveUtils,Random,LinearAlgebra,SparseArrays
+          mode: 'forcedeps'
           julia_version: ${{ matrix.version }}
       - uses: julia-actions/cache@v3
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
+        with:
+          allow_reresolve: false
+          force_latest_compatible_version: false
diff --git a/Project.toml b/Project.toml
index 9e8f697..975bff2 100644
--- a/Project.toml
+++ b/Project.toml
@@ -4,7 +4,7 @@ authors = ["Feroz Ahmed Mian <fmian@umass.edu>", "Stefan Krastanov <stefan@krast
 version = "0.1.0"
 
 [workspace]
-projects = ["docs"]
+projects = ["docs", "test", "test/projects/jet"]
 
 [deps]
 DocStringExtensions = "ffbed154-4ef7-542d-bbb7-c09d3a79fcae"
@@ -22,12 +22,12 @@ SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 
 [compat]
 DocStringExtensions = "0.9.5"
-Graphs = "1.9"
+Graphs = "1.12"
 LinearAlgebra = "1.10"
 Multigraphs = "0.3.0"
-Nemo = "0.45.5, 0.46, 0.47, 0.48, 0.49, 0.50, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56"
-Oscar = "1.1.1"
-PrecompileTools = "1.2"
+Nemo = "0.52.1, 0.53, 0.54, 0.55, 0.56"
+Oscar = "1.5"
+PrecompileTools = "1.3"
 ProgressMeter = "1.11.0"
 QECCore = "0.1.3"
 QuantumClifford = "0.11.3"
diff --git a/src/quantum_tanner_code_multigraphs.jl b/src/quantum_tanner_code_multigraphs.jl
index efc6c77..3cf602a 100644
--- a/src/quantum_tanner_code_multigraphs.jl
+++ b/src/quantum_tanner_code_multigraphs.jl
@@ -17,7 +17,7 @@ Returns `(𝒞ˣ, 𝒞ᶻ)` where `𝒞ˣ` is the X-stabilizer matrix and `𝒞
 - `rate::Real`: Rate parameter for local codes (C_A has rate ρ, C_B has rate 1-ρ)
 - `group`: The group G for the left-right Cayley complex
 - `A`: Symmetric generating set A for the left Cayley graph
-- `B`: Symmetric generating set B for the right Cayley graph  
+- `B`: Symmetric generating set B for the right Cayley graph
 - `bipartite::Bool`: Whether to use bipartite vertex partitioning (V₀, V₁)
 """
 struct GeneralizedQuantumTannerCode <: AbstractCSSCode
@@ -148,14 +148,18 @@ Generate a good Quantum Tanner code meeting minimum weight requirements.
 
 ### Arguments
 - `ρ`: Rate parameter for local codes
-- `group`, `A`, `B`: Expander graph components  
+- `group`, `A`, `B`: Expander graph components
 - `minweight_x`: Minimum weight for X-stabilizers
 - `minweight_z`: Minimum weight for Z-stabilizers
 - `max_iterations`: Maximum attempts to find a good code
+- `rng`: Random number generator used to construct candidate codes
 """
-function gen_good_code(ρ::Real, group::Group, A::Vector{<:GroupElem}, B::Vector{<:GroupElem}; minweight_x=1, minweight_z=1, bipartite=true, use_same_local_code=false, max_iterations=100)
+function gen_good_code(ρ::Real, group::Group, A::Vector{<:GroupElem}, B::Vector{<:GroupElem};
+                       minweight_x=1, minweight_z=1, bipartite=true,
+                       use_same_local_code=false, max_iterations=100,
+                       rng::AbstractRNG=GLOBAL_RNG)
     for i in 1:max_iterations
-        𝒞ˣ, 𝒞ᶻ = random_quantum_Tanner_code(ρ, group, A, B; bipartite, use_same_local_code)
+        𝒞ˣ, 𝒞ᶻ = random_quantum_Tanner_code(ρ, group, A, B; bipartite, use_same_local_code, rng)
         x_weight = minimum(unique(sum(𝒞ˣ, dims=1)))
         z_weight = minimum(unique(sum(𝒞ᶻ, dims=1)))
         if x_weight >= minweight_x && z_weight >= minweight_z
diff --git a/test/Project.toml b/test/Project.toml
index 835aa01..e23641f 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -4,22 +4,29 @@ Graphs = "86223c79-3864-5bf0-83f7-82e725a168b6"
 GraphsColoring = "ed38bb8a-6120-4024-8d1e-8789784f251b"
 HiGHS = "87dc4568-4c63-4d18-b0c0-bb2238e4078b"
 IGraphs = "647e90d3-2106-487c-adb4-c91fc07b96ea"
-LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
-JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
 JuMP = "4076af6c-e467-56ae-b986-b466b2749572"
+LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 LogExpFunctions = "2ab3a3ac-af41-5b50-aa03-7779005ae688"
 Multigraphs = "7ebac608-6c66-46e6-9856-b5f43e107bac"
 NautyGraphs = "7509a0a4-015a-4167-b44b-0799a1a2605e"
 Nemo = "2edaba10-b0f1-5616-af89-8c11ac63239a"
 Oscar = "f1435218-dba5-11e9-1e4d-f1a5fab5fc13"
+Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
 PrecompileTools = "aea7be01-6a6a-4083-8856-8a6e6704d82a"
 Primes = "27ebfcd6-29c5-5fa9-bf4b-fb8fc14df3ae"
 ProgressMeter = "92933f4c-e287-5a05-a399-4b506db050ca"
 QECCore = "b50d4dc9-2544-401f-bae9-a24ba40d0c7a"
 QuantumClifford = "0525e862-1e90-11e9-3e4d-1b39d7109de1"
+QuantumExpanders = "144928dd-1f60-4b66-8c4c-f5ae7409097b"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
-SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 SimpleGraphAlgorithms = "41400c72-0c58-5c16-8579-4ecbce768449"
 SimpleGraphConverter = "205b04f2-f585-4877-a239-566270b3f673"
+SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
+StableRNGs = "860ef19b-820b-49d6-a774-d7a799459cd3"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 TestItemRunner = "f8b46487-2199-4994-9208-9a1283c18c0a"
+
+[compat]
+# Pin native HiGHS before ERGO-Code/HiGHS#3141; remove after a fixed release.
+HiGHS = "=1.19.3"
+StableRNGs = "1"
diff --git a/test/projects/jet/Project.toml b/test/projects/jet/Project.toml
new file mode 100644
index 0000000..e1f2f73
--- /dev/null
+++ b/test/projects/jet/Project.toml
@@ -0,0 +1,12 @@
+[deps]
+JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
+Multigraphs = "7ebac608-6c66-46e6-9856-b5f43e107bac"
+Nemo = "2edaba10-b0f1-5616-af89-8c11ac63239a"
+Oscar = "f1435218-dba5-11e9-1e4d-f1a5fab5fc13"
+Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
+QuantumExpanders = "144928dd-1f60-4b66-8c4c-f5ae7409097b"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+TestItemRunner = "f8b46487-2199-4994-9208-9a1283c18c0a"
+
+[sources]
+QuantumExpanders = {path = "../../.."}
diff --git a/test/runtests.jl b/test/runtests.jl
index 606be6c..7dd9723 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1,3 +1,14 @@
+const JET_PROJECT = normpath(joinpath(@__DIR__, "projects", "jet"))
+const test_args = isempty(ARGS) ? ["general"] : ARGS
+const JET_flag = length(test_args) == 1 && startswith(only(test_args), "jet")
+
+if JET_flag
+    @info "Activating the dedicated JET test environment." project=JET_PROJECT
+    using Pkg
+    Pkg.activate(JET_PROJECT)
+    Pkg.instantiate()
+end
+
 using TestItemRunner
 using QuantumExpanders
 
@@ -5,7 +16,7 @@ using QuantumExpanders
 testfilter = ti -> begin
     exclude = Symbol[]
 
-    if get(ENV, "JET_TEST", "") == "true"
+    if JET_flag
         return :jet in ti.tags
     else
         push!(exclude, :jet)
diff --git a/test/test_jet.jl b/test/test_jet.jl
index ce9e11b..3ca0819 100644
--- a/test/test_jet.jl
+++ b/test/test_jet.jl
@@ -4,7 +4,8 @@ using QuantumExpanders
 
 using Oscar, Multigraphs
 
-rep = report_package("QuantumExpanders";
+rep = report_package(QuantumExpanders;
+    target_modules=(QuantumExpanders,),
     ignored_modules=(
         AnyFrameModule(Nemo),
         AnyFrameModule(Oscar),
diff --git a/test/test_ramanujan_graphs_via_frobenius_groups.jl b/test/test_ramanujan_graphs_via_frobenius_groups.jl
index e93e5fb..5eb75af 100644
--- a/test/test_ramanujan_graphs_via_frobenius_groups.jl
+++ b/test/test_ramanujan_graphs_via_frobenius_groups.jl
@@ -11,6 +11,7 @@
     using QuantumClifford.ECC
     using QuantumClifford.ECC: code_n, code_k
     using Nemo: zero_matrix, base_ring, transpose, rank
+    using StableRNGs: StableRNG
 
     function _is_ramanujanᵧ(g::SimpleGraph, k::Int)
         A = adjacency_matrix(g)
@@ -50,7 +51,7 @@
             @test is_ram
         end
     end
-    
+
     # Frobenius groups with r ≥ 4 of https://arxiv.org/pdf/1503.04075, see Theorem 3.3, page 6.
     @testset "Frobenius Groups r ≥ 4" begin
         large_primes = [11, 13, 17, 19]
@@ -70,15 +71,16 @@
     end
 
     @testset "Quantum Tanner codes from Frobenius Groups" begin
+        rng = StableRNG(1234)
         primes =  [3, 5]
         for p in primes
             for rate in [0.5, 0.6, 0.7]
                 G = dihedral_group(2*p)
                 S = normal_cayley_subset(G)
-                hx, hz = random_quantum_Tanner_code(rate, G, S, S, bipartite=false)
+                hx, hz = random_quantum_Tanner_code(rate, G, S, S; bipartite=false, rng)
                 c = Stabilizer(CSS(hx, hz))
                 @test stab_looks_good(c, remove_redundant_rows=true)
-                hx, hz = gen_good_code(rate, G, S, S, use_same_local_code=true, bipartite=false)
+                hx, hz = gen_good_code(rate, G, S, S; use_same_local_code=true, bipartite=false, rng)
                 c = Stabilizer(CSS(hx, hz))
                 @test stab_looks_good(c, remove_redundant_rows=true)
             end