diff --git a/.github/workflows/python-tests.yml b/.github/workflows/python-tests.yml
index 717001255..7627b9508 100644
--- a/.github/workflows/python-tests.yml
+++ b/.github/workflows/python-tests.yml
@@ -19,13 +19,12 @@ jobs:
       matrix:
         include:
           - os: ubuntu-20.04
-            rust-target: x86_64-unknown-linux-gnu
             python-version: "3.7"
           - os: ubuntu-20.04
-            rust-target: x86_64-unknown-linux-gnu
             python-version: "3.11"
           - os: macos-11
-            rust-target: x86_64-apple-darwin
+            python-version: "3.11"
+          - os: windows-2019
             python-version: "3.11"
     steps:
       - uses: actions/checkout@v3
@@ -39,13 +38,12 @@ jobs:
         uses: dtolnay/rust-toolchain@master
         with:
           toolchain: stable
-          target: ${{ matrix.rust-target }}
 
       - name: install python dependencies
         run: |
           python -m pip install --upgrade pip
           python -m pip install tox
-          echo "tox_version=$(tox --version | awk '{split($0, s," "); print s[1]}')" >> $GITHUB_ENV
+          echo "tox_version=$(python -c 'import tox; print(tox.__version__)')" >> $GITHUB_ENV
 
       - name: Setup sccache
         uses: mozilla-actions/sccache-action@v0.0.3
@@ -95,7 +93,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           python -m pip install tox
-          echo "tox_version=$(tox --version | awk '{split($0, s," "); print s[1]}')" >> $GITHUB_ENV
+          echo "tox_version=$(python -c 'import tox; print(tox.__version__)')" >> $GITHUB_ENV
 
       - name: cache tox environments
         uses: actions/cache@v3
diff --git a/.github/workflows/rust-tests.yml b/.github/workflows/rust-tests.yml
index 78f761910..7a146a3b5 100644
--- a/.github/workflows/rust-tests.yml
+++ b/.github/workflows/rust-tests.yml
@@ -15,6 +15,10 @@ jobs:
     runs-on: ${{ matrix.os }}
     name: ${{ matrix.os }} / rust ${{ matrix.rust-version }} ${{ matrix.extra-name }}
     container: ${{ matrix.container }}
+    env:
+      # this is used on windows to put the compiled code on C:\\ since there is
+      # not enough space on D:\\ (only 12GiB, we need ~14GiB)
+      CARGO_TARGET_DIR: ${{ matrix.cargo-target-dir }}
     strategy:
       matrix:
         include:
@@ -24,6 +28,8 @@ jobs:
             build-type: debug
             test-static-lib: true
             extra-name: / static C library
+            cargo-target-dir: target
+
           - os: ubuntu-20.04
             rust-version: stable
             rust-target: x86_64-unknown-linux-gnu
@@ -31,6 +37,8 @@ jobs:
             cargo-build-flags: --release
             do-valgrind: true
             extra-name: / release valgrind
+            cargo-target-dir: target
+
           # check the build on a stock Ubuntu 20.04, including cmake 3.16
           - os: ubuntu-20.04
             rust-version: "1.64"
@@ -38,10 +46,20 @@ jobs:
             rust-target: x86_64-unknown-linux-gnu
             build-type: debug
             extra-name: / cmake 3.16
+            cargo-target-dir: target
+
           - os: macos-11
             rust-version: stable
             rust-target: x86_64-apple-darwin
             build-type: debug
+            cargo-target-dir: target
+
+          - os: windows-2019
+            rust-version: stable
+            rust-target: x86_64-pc-windows-msvc
+            build-type: debug
+            cargo-target-dir: C:\\cargo-target-rascaline\\
+
     steps:
       - name: install dependencies in container
         if: matrix.container == 'ubuntu:20.04'
diff --git a/.github/workflows/torch-tests.yml b/.github/workflows/torch-tests.yml
index 171b42205..e362acb83 100644
--- a/.github/workflows/torch-tests.yml
+++ b/.github/workflows/torch-tests.yml
@@ -33,6 +33,11 @@ jobs:
             python-version: "3.11"
             cargo-test-flags: --release
 
+          - os: windows-2019
+            torch-version: 2.0.*
+            python-version: "3.11"
+            cargo-test-flags: --release
+
     steps:
       - uses: actions/checkout@v3
 
diff --git a/rascaline-torch/include/rascaline/torch/system.hpp b/rascaline-torch/include/rascaline/torch/system.hpp
index 924ecb3f4..48e599379 100644
--- a/rascaline-torch/include/rascaline/torch/system.hpp
+++ b/rascaline-torch/include/rascaline/torch/system.hpp
@@ -2,7 +2,7 @@
 #define RASCALINE_TORCH_SYSTEM_HPP
 
 #include <vector>
-#include <unordered_map>
+#include <map>
 
 #include <torch/script.h>
 
@@ -138,7 +138,7 @@ class RASCALINE_TORCH_EXPORT SystemHolder final: public rascaline::System, publi
     };
 
     // all precomputed pairs we know about
-    std::unordered_map<double, PrecomputedPairs> precomputed_pairs_;
+    std::map<double, PrecomputedPairs> precomputed_pairs_;
     // last custom requested by `compute_neighbors`
     double last_cutoff_ = -1.0;
 };
diff --git a/rascaline-torch/tests/system.cpp b/rascaline-torch/tests/system.cpp
index a42b784fb..ee594b4f6 100644
--- a/rascaline-torch/tests/system.cpp
+++ b/rascaline-torch/tests/system.cpp
@@ -26,7 +26,7 @@ TEST_CASE("Systems") {
             Catch::Matchers::StartsWith(
                 "trying to get neighbor list with a cutoff (3.3) for which no "
                 "pre-computed neighbor lists has been registered (we have lists "
-                "for cutoff=[4.5, 3.2])"
+                "for cutoff=[3.2, 4.5])"
             )
         );
 
diff --git a/rascaline/src/calculators/radial_basis/gto.rs b/rascaline/src/calculators/radial_basis/gto.rs
index a2a0025b1..4bcca22de 100644
--- a/rascaline/src/calculators/radial_basis/gto.rs
+++ b/rascaline/src/calculators/radial_basis/gto.rs
@@ -94,7 +94,7 @@ mod tests {
         let overlap = basis.overlap();
 
         for i in 0..basis.max_radial {
-            assert_ulps_eq!(overlap[(i, i)], 1.0);
+            assert_ulps_eq!(overlap[(i, i)], 1.0, max_ulps=10);
         }
 
         for i in 0..basis.max_radial {