diff --git a/.github/workflows/unix_impl.yml b/.github/workflows/unix_impl.yml
index 14614bfd07..8fc78a8931 100644
--- a/.github/workflows/unix_impl.yml
+++ b/.github/workflows/unix_impl.yml
@@ -25,6 +25,7 @@ jobs:
       - name: Create build environment
         uses: mamba-org/setup-micromamba@v1
         with:
+          micromamba-version: '1.5.10-0'
           environment-file: ./dev/environment-dev.yml
           environment-name: build_env
           cache-environment: true
@@ -72,6 +73,7 @@ jobs:
       - name: Create build environment
         uses: mamba-org/setup-micromamba@v1
         with:
+          micromamba-version: '1.5.10-0'
           environment-file: ./build/environment.lock
           environment-name: build_env
       - name: Run solv-cpp tests
@@ -98,6 +100,7 @@ jobs:
       - name: Create build environment
         uses: mamba-org/setup-micromamba@v1
         with:
+          micromamba-version: '1.5.10-0'
           environment-file: ./build/environment.lock
           environment-name: build_env
       - name: Install libmambapy
@@ -125,6 +128,7 @@ jobs:
       - name: Create build environment
         uses: mamba-org/setup-micromamba@v1
         with:
+          micromamba-version: '1.5.10-0'
           environment-file: ./build/environment.lock
           environment-name: build_env
       - name: install zsh, xonsh, fish and tcsh in linux
@@ -182,6 +186,7 @@ jobs:
       - name: Create build environment
         uses: mamba-org/setup-micromamba@v1
         with:
+          micromamba-version: '1.5.10-0'
           environment-file: ./build/environment.lock
           environment-name: build_env
       - name: Run tests using conda-content-trust (server side)