diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 09f5a3c..ad087df 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -29,6 +29,7 @@ jobs:
           # Linux, gcc-4.8
           - toolset: gcc-4.8
             cxxstd: "03,11"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:18.04
@@ -37,6 +38,7 @@ jobs:
           # Linux, gcc-4.9
           - toolset: gcc-4.9
             cxxstd: "03,11"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:16.04
@@ -44,6 +46,7 @@ jobs:
               - g++-4.9-multilib
           # Linux, gcc-5
           - toolset: gcc-5
+            cxxflags: -pipe
             cxxstd: "03,11,14,1z"
             address-model: 32,64
             os: ubuntu-latest
@@ -53,6 +56,7 @@ jobs:
           # Linux, gcc-6
           - toolset: gcc-6
             cxxstd: "03,11,14,1z"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:18.04
@@ -61,6 +65,7 @@ jobs:
           # Linux, gcc-7
           - toolset: gcc-7
             cxxstd: "03,11,14,17"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:18.04
@@ -69,6 +74,7 @@ jobs:
           # Linux, gcc-8
           - toolset: gcc-8
             cxxstd: "03,11,14,17,2a"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:18.04
@@ -77,6 +83,7 @@ jobs:
           # Linux, gcc-9
           - toolset: gcc-9
             cxxstd: "03,11,14,17,2a"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:20.04
@@ -85,6 +92,7 @@ jobs:
           # Linux, gcc-10
           - toolset: gcc-10
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:20.04
@@ -93,6 +101,7 @@ jobs:
           # Linux, gcc-11
           - toolset: gcc-11
             cxxstd: "03,11,14,17,20,23"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:22.04
@@ -101,6 +110,7 @@ jobs:
           # Linux, gcc-12
           - toolset: gcc-12
             cxxstd: "03,11,14,17,20,23"
+            cxxflags: -pipe
             address-model: 32,64
             os: ubuntu-latest
             container: ubuntu:22.04
@@ -109,6 +119,7 @@ jobs:
           # Linux, gcc-13
           - toolset: gcc-13
             cxxstd: "11,14,17,20,2b"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:24.04
             install: g++-13-multilib
@@ -116,6 +127,7 @@ jobs:
           # Linux, gcc-14
           - toolset: gcc-14
             cxxstd: "11,14,17,20,2b"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:24.04
             install: g++-14-multilib
@@ -124,6 +136,7 @@ jobs:
           - name: UBSAN
             toolset: gcc-12
             cxxstd: "03,11,14,17,20,23"
+            cxxflags: -pipe
             ubsan: 1
             os: ubuntu-latest
             container: ubuntu:22.04
@@ -132,18 +145,11 @@ jobs:
           #------------------
           # Linux, clang
           #------------------
-          # Linux, clang-3.5
-          - toolset: clang
-            compiler: clang++-3.5
-            cxxstd: "03,11"
-            os: ubuntu-latest
-            container: ubuntu:16.04
-            install:
-              - clang-3.5
           # Linux, clang-3.6
           - toolset: clang
             compiler: clang++-3.6
             cxxstd: "03,11,14"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:16.04
             install:
@@ -152,6 +158,7 @@ jobs:
           - toolset: clang
             compiler: clang++-3.7
             cxxstd: "03,11,14"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:16.04
             install:
@@ -160,6 +167,7 @@ jobs:
           - toolset: clang
             compiler: clang++-3.8
             cxxstd: "03,11,14"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:16.04
             install:
@@ -168,6 +176,7 @@ jobs:
           - toolset: clang
             compiler: clang++-3.9
             cxxstd: "03,11,14"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:18.04
             install:
@@ -176,6 +185,7 @@ jobs:
           - toolset: clang
             compiler: clang++-4.0
             cxxstd: "03,11,14"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:18.04
             install:
@@ -184,6 +194,7 @@ jobs:
           - toolset: clang
             compiler: clang++-5.0
             cxxstd: "03,11,14,1z"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:18.04
             install:
@@ -192,6 +203,7 @@ jobs:
           - toolset: clang
             compiler: clang++-6.0
             cxxstd: "03,11,14,17"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:18.04
             install:
@@ -200,6 +212,7 @@ jobs:
           - toolset: clang
             compiler: clang++-7
             cxxstd: "03,11,14,17"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:18.04
             install:
@@ -209,6 +222,7 @@ jobs:
           - toolset: clang
             compiler: clang++-8
             cxxstd: "03,11,14,17,2a"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:18.04
             install:
@@ -219,6 +233,7 @@ jobs:
           - toolset: clang
             compiler: clang++-9
             cxxstd: "03,11,14,17,2a"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:20.04
             install:
@@ -227,6 +242,7 @@ jobs:
           - toolset: clang
             compiler: clang++-10
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:20.04
             install:
@@ -235,6 +251,7 @@ jobs:
           - toolset: clang
             compiler: clang++-11
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:22.04
             install:
@@ -243,6 +260,7 @@ jobs:
           - toolset: clang
             compiler: clang++-12
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:22.04
             install:
@@ -251,6 +269,7 @@ jobs:
           - toolset: clang
             compiler: clang++-13
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:22.04
             install:
@@ -259,6 +278,7 @@ jobs:
           - toolset: clang
             compiler: clang++-14
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             os: ubuntu-latest
             container: ubuntu:22.04
             install:
@@ -267,12 +287,14 @@ jobs:
           - toolset: clang
             compiler: clang++-15
             cxxstd: "03,11,14,17,20"
+            cxxflags: -pipe
             container: ubuntu:22.04
             os: ubuntu-latest
             install: clang-15
           # Linux, clang-16
           - toolset: clang
             compiler: clang++-16
+            cxxflags: -pipe
             cxxstd: "03,11,14,17,20,2b"
             container: ubuntu:24.04
             os: ubuntu-latest
@@ -281,6 +303,7 @@ jobs:
           - toolset: clang
             compiler: clang++-17
             cxxstd: "03,11,14,17,20,2b"
+            cxxflags: -pipe
             container: ubuntu:24.04
             os: ubuntu-latest
             install: clang-17
@@ -288,6 +311,7 @@ jobs:
           - toolset: clang
             compiler: clang++-18
             cxxstd: "03,11,14,17,20,2b"
+            cxxflags: -pipe
             container: ubuntu:24.04
             os: ubuntu-latest
             install: clang-18
@@ -307,7 +331,7 @@ jobs:
               - clang-15
               - libc++-15-dev
               - libc++abi-15-dev
-            cxxflags: -stdlib=libc++
+            cxxflags: -pipe -stdlib=libc++
             linkflags: -stdlib=libc++
           # Linux, clang-18 libc++
           - toolset: clang
@@ -318,14 +342,14 @@ jobs:
               - clang-18
               - libc++-18-dev
               - libc++abi-18-dev
-            cxxflags: -stdlib=libc++
+            cxxflags: -pipe -stdlib=libc++
             linkflags: -stdlib=libc++
           # Linux, clang-14 libc++, ubsan
           - name: UBSAN
             toolset: clang
             compiler: clang++-14
             cxxstd: "03,11,14,17,20"
-            cxxflags: -stdlib=libc++
+            cxxflags: -pipe -stdlib=libc++
             linkflags: -stdlib=libc++
             ubsan: 1
             os: ubuntu-22.04
@@ -338,7 +362,7 @@ jobs:
             toolset: clang
             compiler: clang++-18
             cxxstd: "11,14,17,20"
-            cxxflags: -stdlib=libc++
+            cxxflags: -pipe -stdlib=libc++
             linkflags: -stdlib=libc++
             ubsan: 1
             os: ubuntu-24.04
@@ -471,6 +495,7 @@ jobs:
             BOOST_BRANCH=develop && [ "$REF" = "master" ] && BOOST_BRANCH=master || true
             echo BOOST_BRANCH: $BOOST_BRANCH
             BUILD_JOBS=$((nproc || sysctl -n hw.ncpu) 2> /dev/null)
+            echo BUILD_JOBS: $BUILD_JOBS
             echo "BUILD_JOBS=$BUILD_JOBS" >> $GITHUB_ENV
             echo "CMAKE_BUILD_PARALLEL_LEVEL=$BUILD_JOBS" >> $GITHUB_ENV
             DEPINST_ARGS=()
@@ -540,7 +565,7 @@ jobs:
         if: matrix.cmake_tests == ''
         run: |
             cd boost-root
-            B2_ARGS=("-j" "$BUILD_JOBS" "toolset=${{matrix.toolset}}" "cxxstd=${{matrix.cxxstd}}")
+            B2_ARGS=("-j" "$BUILD_JOBS" "toolset=${{matrix.toolset}}" "cxxstd=${{matrix.cxxstd}}" "debug-symbols=off")
             if [ -n "${{matrix.build_variant}}" ]
             then
                 B2_ARGS+=("variant=${{matrix.build_variant}}")
@@ -576,9 +601,15 @@ jobs:
       fail-fast: false
       matrix:
         include:
+         #------------------
+         #Windows runners are much slower, split 32/64 bit jobs
           - toolset: msvc-14.3
             cxxstd: "14,17,20,latest"
-            addrmd: 32,64
+            addrmd: 32
+            os: windows-2025
+          - toolset: msvc-14.3
+            cxxstd: "14,17,20,latest"
+            addrmd: 64
             os: windows-2025
           - toolset: clang-win
             cxxstd: "14,17,latest"
@@ -606,6 +637,7 @@ jobs:
             set BOOST_BRANCH=develop
             for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
             echo BOOST_BRANCH: %BOOST_BRANCH%
+            echo NUMBER_OF_PROCESSORS: %NUMBER_OF_PROCESSORS%
             mkdir snapshot
             cd snapshot
             echo Downloading library snapshot: https://github.com/%GITHUB_REPOSITORY%/archive/%GITHUB_SHA%.zip
@@ -633,5 +665,5 @@ jobs:
         shell: cmd
         run: |
             cd boost-root
-            b2 -j %NUMBER_OF_PROCESSORS% libs/%LIBRARY%/test toolset=${{matrix.toolset}} cxxstd=${{matrix.cxxstd}} address-model=${{matrix.addrmd}} variant=debug,release embed-manifest-via=linker
+            b2 -j %NUMBER_OF_PROCESSORS% libs/%LIBRARY%/test toolset=${{matrix.toolset}} cxxstd=${{matrix.cxxstd}} address-model=${{matrix.addrmd}} variant=debug,release embed-manifest-via=linker debug-symbols=off