diff --git a/.github/workflows/continuous_integration.yml b/.github/workflows/continuous_integration.yml
index 270ee1c1c..e1d89c325 100644
--- a/.github/workflows/continuous_integration.yml
+++ b/.github/workflows/continuous_integration.yml
@@ -12,7 +12,7 @@ concurrency:
 
 jobs:
   setup-linux:
-    runs-on: ubuntu
+    runs-on: [self-hosted, Linux, esteco]
     name: Setup - Linux
     steps:
       - name: Checkout build environment information
@@ -33,7 +33,7 @@ jobs:
         run: |
           rm -rf bitpit
   tests-linux:
-    runs-on: ubuntu
+    runs-on: [self-hosted, Linux, esteco]
     needs: setup-linux
     name: Linux (${{ matrix.compiler }}) - MPI ${{ matrix.mpi }} - Debug ${{ matrix.debug }}
     strategy:
@@ -81,7 +81,7 @@ jobs:
           --target bitpit-test \
           -f environments/ubuntu/Dockerfile .
   tests-windows:
-    runs-on: Windows
+    runs-on: [self-hosted, Windows]
     name: Windows (MSVC) - MPI ${{ matrix.mpi }} - Debug ${{ matrix.debug }}
     strategy:
       fail-fast: false
diff --git a/environments/ubuntu/Dockerfile b/environments/ubuntu/Dockerfile
index f0b45e21a..4c5b43df2 100644
--- a/environments/ubuntu/Dockerfile
+++ b/environments/ubuntu/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:20.04 AS bitpit-ubuntu-base
+FROM ubuntu:focal-20250404 AS bitpit-ubuntu-base
 LABEL stage=bitpit-ubuntu-base
 ENV DEBIAN_FRONTEND noninteractive
 RUN sed -i "s/htt[p|ps]:\/\/archive.ubuntu.com\/ubuntu\//mirror:\/\/mirrors.ubuntu.com\/mirrors.txt/g" /etc/apt/sources.list && \