diff --git a/.github/workflows/cmake-linux.yml b/.github/workflows/cmake-linux.yml
index ec2fefd6..aa4efae0 100644
--- a/.github/workflows/cmake-linux.yml
+++ b/.github/workflows/cmake-linux.yml
@@ -26,6 +26,12 @@ jobs:
     steps:
     - uses: actions/checkout@v6
 
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      with:
+        key: ${{ github.job }}
+        max-size: "5G"
+
     - name: Install required packages
       shell: bash
       run: |
@@ -47,7 +53,7 @@ jobs:
       run: |
         mkdir build_linux
         cd build_linux
-        cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=1 ..
+        cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=1 -DCMAKE_C_COMPILER_LAUNCHER=ccache -DCMAKE_CXX_COMPILER_LAUNCHER=ccache ..
         # Build so we have all required .h and .c/.cpp files
         make -j$(nproc)
 
@@ -75,6 +81,20 @@ jobs:
     steps:
     - uses: actions/checkout@v6
 
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      if: ${{ matrix.os == 'ubuntu-22.04-arm' }}
+      with:
+        key: ${{ github.job }}-aarch64
+        max-size: "5G"
+
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      if: ${{ matrix.os == 'ubuntu-22.04' }}
+      with:
+        key: ${{ github.job }}-x86_64
+        max-size: "5G"
+
     - name: Install LLVM/Clang >=20.0 
       run: |
         set -euxo pipefail
@@ -144,7 +164,7 @@ jobs:
       working-directory: ${{github.workspace}}
       run: |
           . ./rade-venv/bin/activate
-          BUILD_TYPE=Release CC=clang-21 CXX=clang++-21 PGO_INSTRUMENT=1 ENABLE_LTO=1 STATIC_LIBGCC=1 ./build_linux.sh 
+          BUILD_TYPE=Release CC=clang-21 CXX=clang++-21 USE_CCACHE=1 PGO_INSTRUMENT=1 ENABLE_LTO=1 STATIC_LIBGCC=1 ./build_linux.sh 
 
     - name: Generate optimization profile
       shell: bash
@@ -457,6 +477,12 @@ jobs:
     #  with:
     #    detached: true
 
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      with:
+        key: ${{ github.job }}-${{ matrix.os }}-${{ matrix.sanitizer }}-${{ matrix.native-audio }}
+        max-size: "5G"
+
     - name: Install LLVM/Clang >=20.0 
       if: ${{ matrix.os == 'ubuntu-24.04' || matrix.os == 'ubuntu-24.04-arm' }}
       run: |
@@ -552,7 +578,7 @@ jobs:
       if: ${{ matrix.sanitizer != 'WITH_ASAN=0' }}
       run: |
           . ./rade-venv/bin/activate
-          UT_ENABLE=1 CC=clang-21 CXX=clang++-21 ${{matrix.native-audio}} ${{matrix.sanitizer}} ./build_linux.sh 
+          UT_ENABLE=1 CC=clang-21 CXX=clang++-21 USE_CCACHE=1 ${{matrix.native-audio}} ${{matrix.sanitizer}} ./build_linux.sh 
 
     - name: Build freedv-gui 
       shell: bash
@@ -560,7 +586,7 @@ jobs:
       if: ${{ matrix.sanitizer == 'WITH_ASAN=0' }}
       run: |
           . ./rade-venv/bin/activate
-          UT_ENABLE=1 CC=clang-21 CXX=clang++-21 ${{matrix.native-audio}} ${{matrix.sanitizer}} ./build_linux.sh 
+          UT_ENABLE=1 CC=clang-21 CXX=clang++-21 USE_CCACHE=1 ${{matrix.native-audio}} ${{matrix.sanitizer}} ./build_linux.sh 
 
     - name: Execute unit tests
       shell: bash
diff --git a/.github/workflows/cmake-macos.yml b/.github/workflows/cmake-macos.yml
index 985dd35c..2afde805 100644
--- a/.github/workflows/cmake-macos.yml
+++ b/.github/workflows/cmake-macos.yml
@@ -20,6 +20,12 @@ jobs:
     steps:
     - uses: actions/checkout@v6
 
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      with:
+        key: ${{ github.job }}
+        max-size: "5G"
+
     - name: Install needed packages
       run: |
           brew install automake libtool numpy sox wxwidgets speexdsp portaudio libsndfile hamlib libebur128 
@@ -42,7 +48,7 @@ jobs:
       run: |
         mkdir build_osx
         cd build_osx
-        CC=clang CXX=clang++ cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=1 ..
+        CC=clang CXX=clang++ cmake -DCMAKE_OBJCXX_COMPILER_LAUNCHER=ccache -DCMAKE_C_COMPILER_LAUNCHER=ccache -DCMAKE_CXX_COMPILER_LAUNCHER=ccache -DCMAKE_EXPORT_COMPILE_COMMANDS=1 ..
         # Build so we have all required .h and .c/.cpp files
         make -j$(sysctl -n hw.logicalcpu)
     
@@ -64,6 +70,13 @@ jobs:
     steps:
     - uses: actions/checkout@v6
 
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      with:
+        key: ${{ github.job }}-${{ matrix.os }}-${{ matrix.sanitizer }}
+        create-symlink: true
+        max-size: "5G"
+
     #- name: Setup tmate session
     #  uses: mxschmitt/action-tmate@v3
     #  with:
@@ -145,6 +158,25 @@ jobs:
     #  with:
     #    detached: true
 
+    # There's a bug where macos-26 ends up downloading macos-26-intel's cache and thus 
+    # having few/no cache hits. To prevent this, we make sure that the cache key is unique
+    # enough on both platforms to avoid inadvertent matches.
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      if: ${{ matrix.os == 'macos-26-intel' }}
+      with:
+        key: ${{ github.job }}-x86_64
+        max-size: "5G"
+        create-symlink: true
+
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      if: ${{ matrix.os == 'macos-26' }}
+      with:
+        key: ${{ github.job }}-aarch64
+        max-size: "5G"
+        create-symlink: true
+
     - name: Install needed packages
       run: |
         brew install automake libtool numpy sox llvm@20 lld@20  # note: LLVM 21 introduces incompatibilities - see https://github.com/Homebrew/homebrew-core/issues/235411
@@ -174,7 +206,7 @@ jobs:
       shell: bash
       working-directory: ${{github.workspace}}
       run: |
-          BUILD_TYPE=Release UT_ENABLE=0 UNIV_BUILD=0 BUILD_DEPS=1 PGO_INSTRUMENT=1 ENABLE_LTO=1 ./build_osx.sh
+          BUILD_TYPE=Release UT_ENABLE=0 UNIV_BUILD=0 BUILD_DEPS=1 PGO_INSTRUMENT=1 ENABLE_LTO=1 USE_CCACHE=1 ./build_osx.sh
 
     - name: Generate optimization profile
       shell: bash
diff --git a/.github/workflows/cmake-windows.yml b/.github/workflows/cmake-windows.yml
index 221ba6a4..4e9372ae 100644
--- a/.github/workflows/cmake-windows.yml
+++ b/.github/workflows/cmake-windows.yml
@@ -28,6 +28,13 @@ jobs:
     steps:
     - uses: actions/checkout@v6
 
+    - name: ccache
+      uses: hendrikmuhs/ccache-action@v1.2.23
+      with:
+        key: ${{ github.job }}-${{ matrix.arch }}
+        max-size: "5G"
+        verbose: 2
+
     - name: Install required packages
       shell: bash
       working-directory: ${{github.workspace}}
@@ -49,7 +56,7 @@ jobs:
         export PATH=${{github.workspace}}/llvm-mingw-20251216-ucrt-ubuntu-22.04-x86_64/bin:$PATH
         mkdir build_windows
         cd build_windows
-        cmake -DENABLE_LTO=1 -DPGO_INSTRUMENT=1 -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_TOOLCHAIN_FILE=${{github.workspace}}/cross-compile/freedv-mingw-llvm-${{ matrix.arch }}.cmake ..
+        cmake -DENABLE_LTO=1 -DPGO_INSTRUMENT=1 -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_C_COMPILER_LAUNCHER=ccache -DCMAKE_CXX_COMPILER_LAUNCHER=ccache -DCMAKE_TOOLCHAIN_FILE=${{github.workspace}}/cross-compile/freedv-mingw-llvm-${{ matrix.arch }}.cmake ..
 
     - name: Build freedv-gui (unsigned)
       shell: bash
diff --git a/USER_MANUAL.md b/USER_MANUAL.md
index a08ed48f..710b6a19 100644
--- a/USER_MANUAL.md
+++ b/USER_MANUAL.md
@@ -992,6 +992,7 @@ LDPC | Low Density Parity Check Codes - a family of powerful FEC codes
     * Require C++20 to build FreeDV. (PR #1440)
     * Enable LTO/PGO for macOS .app build. (PR #1456)
     * Enable PGO for Windows builds. (PR #1457)
+    * Add support for CCache. (PR #1328)
 4. Other:
     * FlexRadio/KA9Q integrations moved to freedv-integrations repo. (PR #1368)
     * Improve tab save/load behavior on systems with wxWidgets 3.3+. (PR #1435)
diff --git a/build_linux.sh b/build_linux.sh
index 886c51ca..6091be9e 100755
--- a/build_linux.sh
+++ b/build_linux.sh
@@ -18,14 +18,21 @@ STATIC_LIBGCC=${STATIC_LIBGCC:-0}
 ENABLE_LTO=${ENABLE_LTO:-0}
 PGO_INSTRUMENT=${PGO_INSTRUMENT:-0}
 PGO_USE_PROFILE=${PGO_USE_PROFILE:-}
+USE_CCACHE=${USE_CCACHE:-0}
 
 export FREEDVGUIDIR=${PWD}
 
+if [ $USE_CCACHE == 1 ]; then
+    CCACHE_ARGS="-DCMAKE_C_COMPILER_LAUNCHER=ccache -DCMAKE_CXX_COMPILER_LAUNCHER=ccache"
+else
+    CCACHE_ARGS=""
+fi
+
 # Finally, build freedv-gui
 cd $FREEDVGUIDIR
 if [ -d .git ]; then
      git pull
 fi
 mkdir  -p build_linux && cd build_linux && rm -Rf *
-cmake -DPGO_INSTRUMENT=${PGO_INSTRUMENT} -DPGO_USE_PROFILE=${PGO_USE_PROFILE} -DENABLE_LTO=${ENABLE_LTO} -DSTATIC_LIBGCC=${STATIC_LIBGCC} -DENABLE_UBSAN=${WITH_UBSAN} -DENABLE_TSAN=${WITH_TSAN} -DENABLE_RTSAN=${WITH_RTSAN} -DENABLE_ASAN=${WITH_ASAN} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} -DUSE_NATIVE_AUDIO=$USE_NATIVE_AUDIO -DUNITTEST=$UT_ENABLE ..
+cmake ${CCACHE_ARGS} -DPGO_INSTRUMENT=${PGO_INSTRUMENT} -DPGO_USE_PROFILE=${PGO_USE_PROFILE} -DENABLE_LTO=${ENABLE_LTO} -DSTATIC_LIBGCC=${STATIC_LIBGCC} -DENABLE_UBSAN=${WITH_UBSAN} -DENABLE_TSAN=${WITH_TSAN} -DENABLE_RTSAN=${WITH_RTSAN} -DENABLE_ASAN=${WITH_ASAN} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} -DUSE_NATIVE_AUDIO=$USE_NATIVE_AUDIO -DUNITTEST=$UT_ENABLE ..
 make -j$(nproc)
diff --git a/build_osx.sh b/build_osx.sh
index d390bc73..349bf542 100755
--- a/build_osx.sh
+++ b/build_osx.sh
@@ -5,7 +5,6 @@
 # lpcnet repos so they are available for parallel development.
 
 export FREEDVGUIDIR=${PWD}
-export HAMLIBDIR=$FREEDVGUIDIR/hamlib
 export UT_ENABLE=${UT_ENABLE:-0}
 export UNIV_BUILD=${UNIV_BUILD:-1}
 export CODESIGN_IDENTITY=${CODESIGN_IDENTITY:--}
@@ -19,6 +18,7 @@ export WITH_UBSAN=${WITH_UBSAN:-0}
 export ENABLE_LTO=${ENABLE_LTO:-0}
 export PGO_INSTRUMENT=${PGO_INSTRUMENT:-0}
 export PGO_USE_PROFILE=${PGO_USE_PROFILE:-}
+export USE_CCACHE=${USE_CCACHE:-0}
 
 # Prerequisite: build dylibbundler
 if [ ! -d macdylibbundler ]; then
@@ -28,25 +28,7 @@ if [ ! -d macdylibbundler ]; then
     cd ..
 fi
 
-# Prerequisite: build hamlib
-cd $FREEDVGUIDIR
-if [ $BUILD_DEPS == 1 ]; then 
-    if [ ! -d hamlib-code ]; then
-        git clone https://github.com/Hamlib/Hamlib.git hamlib-code
-    fi
-    cd hamlib-code && git checkout 4.7.2 && git pull
-    ./bootstrap 
-    if [ $UNIV_BUILD == 1 ]; then
-        CFLAGS="-g -O3 -mmacosx-version-min=11.0 -arch x86_64 -arch arm64" CXXFLAGS="-g -O3 -mmacosx-version-min=11.0 -arch x86_64 -arch arm64" ./configure --enable-shared --prefix $HAMLIBDIR --without-libusb
-    else
-        CFLAGS="-g -O3 -mmacosx-version-min=11.0" CXXFLAGS="-g -O3 -mmacosx-version-min=11.0" ./configure --enable-shared --prefix $HAMLIBDIR --without-libusb
-    fi
-
-    make -j$(sysctl -n hw.logicalcpu) 
-    make install 
-fi
-
-# Finally, build freedv-gui
+# Build freedv-gui
 cd $FREEDVGUIDIR
 if [ -d .git ]; then
     git pull
@@ -57,10 +39,16 @@ if [ "$CODESIGN_KEYCHAIN_PROFILE" != "" ]; then
     export CODESIGN_KEYCHAIN_PROFILE_ARG=-DMACOS_CODESIGN_KEYCHAIN_PROFILE=$CODESIGN_KEYCHAIN_PROFILE
 fi
 
-if [ $BUILD_DEPS == 1 ]; then 
-    cmake -DCMAKE_AR=/usr/bin/ar -DCMAKE_RANLIB=/usr/bin/ranlib -DPGO_INSTRUMENT=${PGO_INSTRUMENT} -DPGO_USE_PROFILE=${PGO_USE_PROFILE} -DENABLE_LTO=${ENABLE_LTO} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} -DENABLE_UBSAN=${WITH_UBSAN} -DENABLE_TSAN=${WITH_TSAN} -DENABLE_RTSAN=${WITH_RTSAN} -DENABLE_ASAN=${WITH_ASAN} -DUSE_NATIVE_AUDIO=$USE_NATIVE_AUDIO -DBUILD_OSX_UNIVERSAL=${UNIV_BUILD} -DUNITTEST=$UT_ENABLE -DBOOTSTRAP_WXWIDGETS=1 -DUSE_STATIC_SPEEXDSP=1 -DUSE_STATIC_PORTAUDIO=1 -DUSE_STATIC_SAMPLERATE=1 -DUSE_STATIC_SNDFILE=1 -DUSE_STATIC_LIBRESSL=1 -DHAMLIB_INCLUDE_DIR=${HAMLIBDIR}/include -DHAMLIB_LIBRARY=${HAMLIBDIR}/lib/libhamlib.dylib -DMACOS_CODESIGN_IDENTITY=${CODESIGN_IDENTITY} ${CODESIGN_KEYCHAIN_PROFILE_ARG} ..
+if [ $USE_CCACHE == 1 ]; then
+    CCACHE_ARGS=-DCMAKE_C_COMPILER_LAUNCHER=ccache -DCMAKE_CXX_COMPILER_LAUNCHER=ccache -DCMAKE_OBJCXX_COMPILER_LAUNCHER=ccache
 else
-    cmake -DCMAKE_AR=/usr/bin/ar -DCMAKE_RANLIB=/usr/bin/ranlib -DPGO_INSTRUMENT=${PGO_INSTRUMENT} -DPGO_USE_PROFILE=${PGO_USE_PROFILE} -DENABLE_LTO=${ENABLE_LTO} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} -DENABLE_UBSAN=${WITH_UBSAN} -DENABLE_TSAN=${WITH_TSAN} -DENABLE_RTSAN=${WITH_RTSAN} -DENABLE_ASAN=${WITH_ASAN} -DUSE_NATIVE_AUDIO=$USE_NATIVE_AUDIO -DBUILD_OSX_UNIVERSAL=${UNIV_BUILD} -DUNITTEST=$UT_ENABLE -DMACOS_CODESIGN_IDENTITY=${CODESIGN_IDENTITY} ${CODESIGN_KEYCHAIN_PROFILE_ARG} ..
+    CCACHE_ARGS=
+fi
+
+if [ $BUILD_DEPS == 1 ]; then 
+    cmake ${CCACHE_ARGS} -DCMAKE_AR=/usr/bin/ar -DCMAKE_RANLIB=/usr/bin/ranlib -DPGO_INSTRUMENT=${PGO_INSTRUMENT} -DPGO_USE_PROFILE=${PGO_USE_PROFILE} -DENABLE_LTO=${ENABLE_LTO} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} -DENABLE_UBSAN=${WITH_UBSAN} -DENABLE_TSAN=${WITH_TSAN} -DENABLE_RTSAN=${WITH_RTSAN} -DENABLE_ASAN=${WITH_ASAN} -DUSE_NATIVE_AUDIO=$USE_NATIVE_AUDIO -DBUILD_OSX_UNIVERSAL=${UNIV_BUILD} -DUNITTEST=$UT_ENABLE -DBOOTSTRAP_WXWIDGETS=1 -DUSE_STATIC_SPEEXDSP=1 -DUSE_STATIC_PORTAUDIO=1 -DUSE_STATIC_SAMPLERATE=1 -DUSE_STATIC_SNDFILE=1 -DUSE_STATIC_LIBRESSL=1 -DMACOS_CODESIGN_IDENTITY=${CODESIGN_IDENTITY} ${CODESIGN_KEYCHAIN_PROFILE_ARG} ..
+else
+    cmake ${CCACHE_ARGS} -DCMAKE_AR=/usr/bin/ar -DCMAKE_RANLIB=/usr/bin/ranlib -DPGO_INSTRUMENT=${PGO_INSTRUMENT} -DPGO_USE_PROFILE=${PGO_USE_PROFILE} -DENABLE_LTO=${ENABLE_LTO} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} -DENABLE_UBSAN=${WITH_UBSAN} -DENABLE_TSAN=${WITH_TSAN} -DENABLE_RTSAN=${WITH_RTSAN} -DENABLE_ASAN=${WITH_ASAN} -DUSE_NATIVE_AUDIO=$USE_NATIVE_AUDIO -DBUILD_OSX_UNIVERSAL=${UNIV_BUILD} -DUNITTEST=$UT_ENABLE -DMACOS_CODESIGN_IDENTITY=${CODESIGN_IDENTITY} ${CODESIGN_KEYCHAIN_PROFILE_ARG} ..
 fi
 
 make -j$(sysctl -n hw.logicalcpu)