diff --git a/.ci/compile.sh b/.ci/compile.sh
index 1588c0d5f..6f51bc476 100755
--- a/.ci/compile.sh
+++ b/.ci/compile.sh
@@ -11,9 +11,8 @@
 # --debug or --release sets the build type ie CMAKE_BUILD_TYPE
 # --ccache [<size>] uses ccache and shows stats, optionally provide size
 # --dir <dir> sets the name of the build dir, default is "build"
-# --parallel <core count> sets how many cores cmake should build with in parallel
-# uses env: BUILDTYPE MAKE_INSTALL MAKE_PACKAGE PACKAGE_TYPE PACKAGE_SUFFIX MAKE_SERVER MAKE_TEST USE_CCACHE CCACHE_SIZE BUILD_DIR PARALLEL_COUNT
-# (correspond to args: --debug/--release --install --package <package type> --suffix <suffix> --server --test --ccache <ccache_size> --dir <dir> --parallel <core_count>)
+# uses env: BUILDTYPE MAKE_INSTALL MAKE_PACKAGE PACKAGE_TYPE PACKAGE_SUFFIX MAKE_SERVER MAKE_TEST USE_CCACHE CCACHE_SIZE BUILD_DIR CMAKE_GENERATOR
+# (correspond to args: --debug/--release --install --package <package type> --suffix <suffix> --server --test --ccache <ccache_size> --dir <dir>)
 # exitcode: 1 for failure, 3 for invalid arguments
 
 # Read arguments
@@ -76,15 +75,6 @@ while [[ $# != 0 ]]; do
       BUILD_DIR="$1"
       shift
       ;;
-    '--parallel')
-      shift
-      if [[ $# == 0 ]]; then
-        echo "::error file=$0::--parallel expects an argument"
-        exit 3
-      fi
-      PARALLEL_COUNT="$1"
-      shift
-      ;;
     *)
       echo "::error file=$0::unrecognized option: $1"
       exit 3
@@ -126,16 +116,6 @@ fi
 
 # Add cmake --build flags
 buildflags=(--config "$BUILDTYPE")
-if [[ $PARALLEL_COUNT ]]; then
-  if [[ $(cmake --build /not_a_dir --parallel 2>&1 | head -1) =~ parallel ]]; then
-    # workaround for bionic having an old cmake
-    echo "this version of cmake does not support --parallel, using native build tool -j instead"
-    buildflags+=(-- -j "$PARALLEL_COUNT")
-    # note, no normal build flags should be added after this
-  else
-    buildflags+=(--parallel "$PARALLEL_COUNT")
-  fi
-fi
 
 function ccachestatsverbose() {
   # note, verbose only works on newer ccache, discard the error
diff --git a/.github/workflows/desktop-build.yml b/.github/workflows/desktop-build.yml
index ea0be461c..59e4d5005 100644
--- a/.github/workflows/desktop-build.yml
+++ b/.github/workflows/desktop-build.yml
@@ -161,7 +161,7 @@ jobs:
           CMAKE_GENERATOR: '${{env.CMAKE_GENERATOR}}'
         run: |
           source .ci/docker.sh
-          RUN --server --debug --test --ccache "$CCACHE_SIZE" --parallel 4
+          RUN --server --debug --test --ccache "$CCACHE_SIZE"
 
       - name: Build release package
         id: build
@@ -175,7 +175,7 @@ jobs:
         run: |
           source .ci/docker.sh
           RUN --server --release --package "$type" --dir "$BUILD_DIR" \
-                  --ccache "$CCACHE_SIZE" --parallel 4
+                  --ccache "$CCACHE_SIZE"
           .ci/name_build.sh
 
       - name: Upload artifact
@@ -206,7 +206,6 @@ jobs:
             os: macos-13
             xcode: "14.3.1"
             type: Release
-            core_count: 4
             make_package: 1
 
           - target: 14
@@ -214,7 +213,6 @@ jobs:
             os: macos-14
             xcode: "15.4"
             type: Release
-            core_count: 3
             make_package: 1
 
           - target: 15
@@ -222,7 +220,6 @@ jobs:
             os: macos-15
             xcode: "16.2"
             type: Release
-            core_count: 3
             make_package: 1
 
           - target: 15
@@ -230,7 +227,6 @@ jobs:
             os: macos-15
             xcode: "16.2"
             type: Debug
-            core_count: 3
 
     name: macOS ${{matrix.target}}${{ matrix.soc == 'Intel' && ' Intel' || '' }}${{ matrix.type == 'Debug' && ' Debug' || '' }}
     needs: configure
@@ -268,9 +264,6 @@ jobs:
           MACOS_CERTIFICATE_NAME: ${{ secrets.PROD_MACOS_CERTIFICATE_NAME }}
           MACOS_CI_KEYCHAIN_PWD: ${{ secrets.PROD_MACOS_CI_KEYCHAIN_PWD }}
           CMAKE_GENERATOR: '${{env.CMAKE_GENERATOR}}'
-        # macOS runner have 3 cores usually - only the macos-13 image has 4:
-        # https://docs.github.com/en/actions/using-github-hosted-runners/using-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for-public-repositories
-        # https://github.com/actions/runner-images?tab=readme-ov-file#available-images
         run: |
           if [[ -n "$MACOS_CERTIFICATE_NAME" ]]
           then
@@ -282,7 +275,7 @@ jobs:
             security import certificate.p12 -k build.keychain -P "$MACOS_CERTIFICATE_PWD" -T /usr/bin/codesign
             security set-key-partition-list -S apple-tool:,apple:,codesign: -s -k "$MACOS_CI_KEYCHAIN_PWD" build.keychain
           fi
-          .ci/compile.sh --server --parallel ${{matrix.core_count}}
+          .ci/compile.sh --server
 
       - name: Sign app bundle
         if: matrix.make_package