diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index dfeaa78787a0aba72768cf1b913865e2c482cc69..06b696f40da969c819bb5bb734ee25dd5c55b66b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -12,24 +12,24 @@ image: gitlab.kwant-project.org:5005/qt/research-docker
 
 test minimal requirements:
   script:
-    - conda env create -f environment-minimal.yml
+    - mamba env create -f environment-minimal.yml
     - source activate qsymm-minimal
     - py.test qsymm/ --cov=qsymm --verbose --cov-report term
   stage: test
 
 test latest requirements:
   script:
-    - conda env create -f environment-latest.yml
+    - mamba env create -f environment-latest.yml
     - source activate qsymm-latest
     - py.test qsymm/ --cov=qsymm --verbose --cov-report term
   stage: test
 
 test kwant against latest qsymm:
   script:
-    - conda env create -f environment-latest.yml
+    - mamba env create -f environment-latest.yml
     - source activate qsymm-latest
     # Get bleeding-edge Kwant
-    - conda install cython
+    - mamba install cython
     - pip install .  # need to install qsymm so that the kwant test can find it
     - pip install git+https://gitlab.kwant-project.org/kwant/kwant.git@stable
     - export KWANT_QSYMM_PATH=$(python -c "$KWANT_QSYMM_TEST_PATH_SCRIPT")
diff --git a/environment-latest.yml b/environment-latest.yml
index b428f1e1c0bfc69b9d8bbb2b233e8739b071c774..985f2e0eef684ca827f6011d38fb467ae956aed6 100644
--- a/environment-latest.yml
+++ b/environment-latest.yml
@@ -2,7 +2,7 @@ name: qsymm-latest
 channels:
     - conda-forge
 dependencies:
-    - python=3.10
+    - python=3.11
     - numpy
     - scipy
     - sympy