diff --git a/.github/workflows/fbf-test.yaml b/.github/workflows/fbf-test.yaml
index 32c0deb1..b72ffdad 100644
--- a/.github/workflows/fbf-test.yaml
+++ b/.github/workflows/fbf-test.yaml
@@ -2,69 +2,35 @@ on:
   pull_request:
   workflow_dispatch:
 env:
-  CONDA_TYPE: Mambaforge
-  CONDA_VERSION: 23.1.0-1
+  CONDA_IMAGE: condaforge/mambaforge:23.1.0-1
   CONDA_PATH: /opt/conda
-  CONDA_CACHEBUST: 1
-  FBF_ENV_CACHEBUST: 1
+  FBF_CACHEBUST: 1
 jobs:
   test:
     name: fbf-test
     runs-on: ubuntu-22.04
+    container:
+      image: ${{env.CONDA_IMAGE}}
     steps:
       - uses: actions/checkout@v3
 
-      - name: restore miniconda cache
-        id: restore-miniconda
-        uses: actions/cache/restore@v3
-        with:
-          path: ${{env.CONDA_PATH}}
-          key: miniconda-${{env.CONDA_TYPE}}-${{env.CONDA_VERSION}}-${{env.CONDA_CACHEBUST}}
-
-      # I tried and rejected the existing setup-miniconda action,
-      # because it wipes out a bunch of files like ~/.profile,
-      # ~/.bashrc, ~/.bash_profile in a way that (a) won't interact
-      # well with other actions that also need to modify the shell
-      # environment, and (b) doesn't play well with caching (you can't
-      # cache the deletion of a file). Also this way seems to take
-      # about half the time (though that might just be random
-      # variation).
-      - name: download miniconda
-        run: curl -L --no-progress-meter -o miniconda-installer.sh "https://github.com/conda-forge/miniforge/releases/download/${{env.CONDA_VERSION}}/${{env.CONDA_TYPE}}-${{env.CONDA_VERSION}}-Linux-x86_64.sh"
-        if: steps.restore-miniconda.outputs.cache-hit != 'true'
-
-      - name: run miniconda installer
-        run: bash miniconda-installer.sh -b -p ${{env.CONDA_PATH}}
-        if: steps.restore-miniconda.outputs.cache-hit != 'true'
-
-      - name: clean up miniconda to reduce cache size
-        run: rm miniconda-installer.sh && source ${{env.CONDA_PATH}}/etc/profile.d/conda.sh && conda clean -afy
-        if: steps.restore-miniconda.outputs.cache-hit != 'true'
-
-      - name: save miniconda cache
-        uses: actions/cache/save@v3
-        with:
-          path: ${{env.CONDA_PATH}}
-          key: miniconda-${{env.CONDA_TYPE}}-${{env.CONDA_VERSION}}-${{env.CONDA_CACHEBUST}}
-        if: steps.restore-miniconda.outputs.cache-hit != 'true'
-
       - name: restore fbfmaproom conda environment cache
         id: restore-fbfmaproom-env
         uses: actions/cache/restore@v3
         with:
           path: ${{env.CONDA_PATH}}/envs/fbfmaproom
-          key: fbfmaproom-env-${{ hashFiles('fbfmaproom/conda-linux-64.lock') }}-${{env.CONDA_CACHEBUST}}-${{env.FBF_ENV_CACHEBUST}}
+          key: fbfmaproom-env-${{CONDA_IMAGE}}-${{ hashFiles('fbfmaproom/conda-linux-64.lock') }}-${{env.FBF_CACHEBUST}}
 
       - name: install fbfmaproom dependencies
-        run: source ${{env.CONDA_PATH}}/etc/profile.d/conda.sh && mamba create -n fbfmaproom --file fbfmaproom/conda-linux-64.lock
+        run: mamba create -n fbfmaproom --file fbfmaproom/conda-linux-64.lock
         if: steps.restore-fbfmaproom-env.outputs.cache-hit != 'true'
 
       - name: save fbfmaproom conda environment cache
         uses: actions/cache/save@v3
         with:
           path: ${{env.CONDA_PATH}}/envs/fbfmaproom
-          key: fbfmaproom-env-${{ hashFiles('fbfmaproom/conda-linux-64.lock') }}-${{env.CONDA_CACHEBUST}}-${{env.FBF_ENV_CACHEBUST}}
+          key: fbfmaproom-env-${{ hashFiles('fbfmaproom/conda-linux-64.lock') }}-${{env.FBF_CACHEBUST}}
         if: steps.restore-fbfmaproom-env.outputs.cache-hit != 'true'
 
       - name: run fbf tests
-        run: source ${{env.CONDA_PATH}}/etc/profile.d/conda.sh && conda activate fbfmaproom && cd fbfmaproom && CONFIG=fbfmaproom-sample.yaml python -m pytest tests/test_pingrid.py
+        run: conda activate fbfmaproom && cd fbfmaproom && CONFIG=fbfmaproom-sample.yaml python -m pytest tests/test_pingrid.py