diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fea1174c..5cefb72f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -225,6 +225,13 @@ jobs:
           BDDE_ARCH: ${{matrix.arch}}
         run: ci/github/setup_bdde.sh
 
+      - name: Cache Boost checkout
+        uses: actions/cache@v4
+        with:
+          path: boost-root
+          key: boost-checkout-cache-${{matrix.os}}-${{matrix.container}}-${{github.sha}}
+          restore-keys: boost-checkout-cache-${{matrix.os}}-${{matrix.container}}-
+
       - name: Setup Boost
         env:
           B2_ADDRESS_MODEL: ${{matrix.address-model}}
@@ -272,6 +279,10 @@ jobs:
           COVERITY_SCAN_NOTIFICATION_EMAIL: ${{ secrets.COVERITY_SCAN_NOTIFICATION_EMAIL }}
           COVERITY_SCAN_TOKEN: ${{ secrets.COVERITY_SCAN_TOKEN }}
 
+      - name: Prepare for cache
+        if: ${{ env.BOOST_ROOT_CACHE != '' }}
+        run: rm -rf boost-root; mv "${BOOST_ROOT_CACHE}" boost-root
+        working-directory: ${{github.workspace}}
   windows:
     defaults:
       run:
diff --git a/ci/common_install.sh b/ci/common_install.sh
index 91fddbcc..3b5c09b5 100644
--- a/ci/common_install.sh
+++ b/ci/common_install.sh
@@ -43,6 +43,8 @@ else
     export BOOST_BRANCH="develop"
 fi
 
+# CI cache might have restored the boost-root folder in the current directory
+[ ! -d boost-root ] || mv boost-root ..
 cd ..
 
 if [ ! -d boost-root ]; then
@@ -176,9 +178,10 @@ if [[ "$B2_DONT_BOOTSTRAP" != "1" ]]; then
     trap show_bootstrap_log ERR
     # Check if b2 already exists. This would (only) happen in a caching scenario. The purpose of caching is to save time by not recompiling everything.
     # The user may clear cache or delete b2 beforehand if they wish to rebuild.
-    if [ ! -f b2 ] || ! b2_version_output=$(./b2 --version); then
+    if [ ! -f b2 ]; then
         ${B2_WRAPPER} ./bootstrap.sh
     else
+        b2_version_output=$(./b2 --version)
         # b2 expects versions to match
         engineversion=$(echo "$b2_version_output" | tr -s ' ' | cut -d' ' -f2 | cut -d'-' -f1)
         enginemajorversion=$(echo "${engineversion}" | cut -d'.' -f1)
@@ -188,6 +191,11 @@ if [[ "$B2_DONT_BOOTSTRAP" != "1" ]]; then
         if [[ "${enginemajorversion}" == "${coremajorversion}" ]] && [[ "${engineminorversion}" == "${coreminorversion}" ]]; then
             echo "b2 already exists and has the same version number"
         else
+            if [[ "$engineversion" =~ ^[0-9]\.[0-9]\. ]]; then
+                echo "b2 binary version: $enginemajorversion:$engineminorversion vs source version $coremajorversion:$coreminorversion"
+            else
+                echo "Unable to extract B2 version from $b2_version_output"
+            fi
             ${B2_WRAPPER} ./bootstrap.sh
         fi
     fi
diff --git a/ci/github/install.sh b/ci/github/install.sh
index c45cc798..60049679 100644
--- a/ci/github/install.sh
+++ b/ci/github/install.sh
@@ -33,6 +33,11 @@ fi
 
 . $(dirname "${BASH_SOURCE[0]}")/../common_install.sh
 
+# Save the state before building anything to avoid caching build artefacts
+BOOST_ROOT_CACHE="${BOOST_ROOT}-for-cache"
+echo "BOOST_ROOT_CACHE=$BOOST_ROOT_CACHE" >> $GITHUB_ENV
+cp -r "$BOOST_ROOT" "$BOOST_ROOT_CACHE"
+
 # Persist the environment for all future steps
 
 # Set by common_install.sh