diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e00b68835..8dc95eca7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -44,6 +44,11 @@ jobs:
           arch: ${{ matrix.arch }}
       - uses: julia-actions/cache@v2
       - uses: julia-actions/julia-buildpkg@v1
+      - name: "Inject Oscar as test dependency (if not Windows and not threaded)"
+        if: ${{ matrix.os != 'windows-latest' && matrix.threads == 1 }}
+        continue-on-error: true
+        run: |
+          sed -i -e "s/\[deps\]/[deps]\nOscar = \"f1435218-dba5-11e9-1e4d-f1a5fab5fc13\"/" test/Project.toml
       - uses: julia-actions/julia-runtest@v1
         env:
           JULIA_NUM_THREADS: ${{ matrix.threads }}
diff --git a/test/Project.toml b/test/Project.toml
index c69088264..cd15ae310 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -16,7 +16,6 @@ LDPCDecoders = "3c486d74-64b9-4c60-8b1a-13a564e77efb"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 MacroTools = "1914dd2f-81c6-5fcd-8719-6d5c9610ff09"
 Nemo = "2edaba10-b0f1-5616-af89-8c11ac63239a"
-Oscar = "f1435218-dba5-11e9-1e4d-f1a5fab5fc13"
 PyQDecoders = "17f5de1a-9b79-4409-a58d-4d45812840f7"
 Quantikz = "b0d11df0-eea3-4d79-b4a5-421488cbf74b"
 QuantumInterface = "5717a53b-5d69-4fa3-b976-0bf2f97ca1e5"
diff --git a/test/test_ecc_base.jl b/test/test_ecc_base.jl
index e458fcb65..68449f658 100644
--- a/test/test_ecc_base.jl
+++ b/test/test_ecc_base.jl
@@ -6,7 +6,6 @@ using InteractiveUtils
 import Nemo: GF
 import LinearAlgebra
 import Hecke: group_algebra, abelian_group, gens, quo, one
-import Oscar: free_group
 
 # generate instances of all implemented codes to make sure nothing skips being checked
 
@@ -44,6 +43,10 @@ test_gb_codes = [
 
 other_lifted_product_codes = []
 
+# Add some codes that require Oscar, hence do not work on Windows
+
+test_twobga_codes = []
+
 # [[882, 24, d≤24]] code from (B1) in Appendix B of [panteleev2021degenerate](@cite)
 l = 63
 GA = group_algebra(GF(2), abelian_group(l))
@@ -57,47 +60,57 @@ A[LinearAlgebra.diagind(A, 5)] .= GA(1)
 B = reshape([1 + x + x^6], (1, 1))
 push!(other_lifted_product_codes, LPCode(A, B))
 
-# [[72, 8, 9]] 2BGA code taken from Table I Block 1 of [lin2024quantum](@cite)
-F = free_group(["r"])
-r = gens(F)[1]
-G, = quo(F, [r^36])
-GA = group_algebra(GF(2), G)
-r = gens(G)[1]
-a = [one(G), r^28]
-b = [one(G), r, r^18, r^12, r^29, r^14]
-t1b1 = twobga_from_fp_group(a, b, GA)
-
-# [[54, 6, 9]] 2BGA code taken from Table I Block 3 of [lin2024quantum](@cite)
-F = free_group(["r"])
-r = gens(F)[1]
-G, = quo(F, [r^27])
-GA = group_algebra(GF(2), G)
-r = gens(G)[1]
-a = [one(G), r, r^3, r^7]
-b = [one(G), r, r^12, r^19]
-t1b3 = twobga_from_fp_group(a, b, GA)
-
-# [[16, 4, 4]] 2BGA taken from Appendix C, Table II of [lin2024quantum](@cite)
-F = free_group(["x", "s"])
-x, s = gens(F)
-G, = quo(F, [x^4, s^2, x * s * x^-1 * s^-1])
-GA = group_algebra(GF(2), G)
-x, s = gens(G)
-a = [one(G), x]
-b = [one(G), x, s, x^2, s*x, x^3]
-tb21 = twobga_from_fp_group(a, b, GA)
-
-# [[32, 8, 4]] 2BGA taken from Appendix C, Table II of [lin2024quantum](@cite)
-F = free_group(["x", "s"])
-x, s = gens(F)
-G, = quo(F, [x^8, s^2, x * s * x^-1 * s^-1])
-GA = group_algebra(GF(2), G)
-x, s = gens(G)
-a = [one(G), x^6]
-b = [one(G), s * x^7, s * x^4, x^6, s * x^5, s * x^2]
-tb22 = twobga_from_fp_group(a, b, GA)
-
-test_twobga_codes = [t1b1, t1b3, tb21, tb22]
+@static if !Sys.iswindows()
+  try
+    import Oscar: free_group
+    @info "Add group theoretic codes requiring Oscar"
+    # [[72, 8, 9]] 2BGA code taken from Table I Block 1 of [lin2024quantum](@cite)
+    F = free_group(["r"])
+    r = gens(F)[1]
+    G, = quo(F, [r^36])
+    GA = group_algebra(GF(2), G)
+    r = gens(G)[1]
+    a = [one(G), r^28]
+    b = [one(G), r, r^18, r^12, r^29, r^14]
+    t1b1 = twobga_from_fp_group(a, b, GA)
+
+    # [[54, 6, 9]] 2BGA code taken from Table I Block 3 of [lin2024quantum](@cite)
+    F = free_group(["r"])
+    r = gens(F)[1]
+    G, = quo(F, [r^27])
+    GA = group_algebra(GF(2), G)
+    r = gens(G)[1]
+    a = [one(G), r, r^3, r^7]
+    b = [one(G), r, r^12, r^19]
+    t1b3 = twobga_from_fp_group(a, b, GA)
+
+    # [[16, 4, 4]] 2BGA taken from Appendix C, Table II of [lin2024quantum](@cite)
+    F = free_group(["x", "s"])
+    x, s = gens(F)
+    G, = quo(F, [x^4, s^2, x * s * x^-1 * s^-1])
+    GA = group_algebra(GF(2), G)
+    x, s = gens(G)
+    a = [one(G), x]
+    b = [one(G), x, s, x^2, s*x, x^3]
+    tb21 = twobga_from_fp_group(a, b, GA)
+
+    # [[32, 8, 4]] 2BGA taken from Appendix C, Table II of [lin2024quantum](@cite)
+    F = free_group(["x", "s"])
+    x, s = gens(F)
+    G, = quo(F, [x^8, s^2, x * s * x^-1 * s^-1])
+    GA = group_algebra(GF(2), G)
+    x, s = gens(G)
+    a = [one(G), x^6]
+    b = [one(G), s * x^7, s * x^4, x^6, s * x^5, s * x^2]
+    tb22 = twobga_from_fp_group(a, b, GA)
+
+    append!(test_twobga_codes, [t1b1, t1b3, tb21, tb22])
+  catch e
+    @warn(e)
+  end
+end
+
+@info "length(test_twobga_codes): $(length(test_twobga_codes))"
 
 const code_instance_args = Dict(
     :Toric => [(3,3), (4,4), (3,6), (4,3), (5,5)],