diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 74d14def..1e22f89e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -44,7 +44,7 @@ jobs:
           # Linux, gcc
           - { compiler: gcc-7,     cxxstd: '03,11,14,17',    os: ubuntu-20.04, install: 'g++-7' }
           - { compiler: gcc-8,     cxxstd: '03,11,14,17',    os: ubuntu-20.04, install: 'g++-8' }
-          - { compiler: gcc-9,     cxxstd: '03,11,14,17',    os: ubuntu-20.04, install: 'g++-9' }
+          - { compiler: gcc-9,     cxxstd: '03,11,14,17',    os: ubuntu-22.04, install: 'g++-9' }
           - { compiler: gcc-10,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04, install: 'g++-10' }
           - { compiler: gcc-11,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04, install: 'g++-11' }
           - { name: "gcc-12 w/ sanitizers (03,11,14)", sanitize: yes,
@@ -54,8 +54,8 @@ jobs:
           - { name: Collect coverage, coverage: yes,
               compiler: gcc-12,     cxxstd: '03,20',          os: ubuntu-22.04, install: 'g++-12-multilib', address-model: '32,64', ccache_key: "cov" }
 
-          - { name: "cfoa tsan (gcc)", cxxstd: '11,14,17,20,2b', os: ubuntu-22.04, compiler: gcc-12,
-              targets: 'libs/unordered/test//cfoa_tests', thread-sanitize: yes }
+          - { name: "cfoa tsan (gcc-12)", cxxstd: '11,14,17,20,2b', os: ubuntu-22.04, compiler: gcc-12,
+              targets: 'libs/unordered/test//cfoa_tests', thread-sanitize: yes, ccache_key: "tsan" }
 
           # Linux, clang, libc++
           - { compiler: clang-7,   cxxstd: '03,11,14,17',       os: ubuntu-20.04, stdlib: libc++, install: 'clang-7 libc++-7-dev libc++abi-7-dev' }
@@ -67,7 +67,6 @@ jobs:
           - { name: "clang-12 w/ sanitizers (17,20,2b)", sanitize: yes,
               compiler: clang-12,  cxxstd: '17,20,2b',          os: ubuntu-20.04, stdlib: libc++, install: 'clang-12 libc++-12-dev libc++abi-12-dev', ccache_key: "san2" }
           - { compiler: clang-13,  cxxstd: '03,11,14,17,20,2b', os: ubuntu-22.04, stdlib: libc++, install: 'clang-13 libc++-13-dev libc++abi-13-dev' }
-          - { compiler: clang-14,  cxxstd: '03,11,14,17,20,2b', os: ubuntu-22.04, stdlib: libc++, install: 'clang-14 libc++-14-dev libc++abi-14-dev' }
 
           # not using libc++ because of https://github.com/llvm/llvm-project/issues/52771
           - { name: "clang-14 w/ sanitizers (03,11,14)", sanitize: yes,
@@ -75,16 +74,19 @@ jobs:
           - { name: "clang-14 w/ sanitizers (17,20,2b)", sanitize: yes,
               compiler: clang-14,  cxxstd: '17,20,2b',          os: ubuntu-22.04, ccache_key: "san2" }
 
-          - { name: "cfoa tsan (clang)", cxxstd: '11,14,17,20,2b', os: ubuntu-22.04, compiler: clang-14,
+          - { name: "cfoa tsan (clang-14)", cxxstd: '11,14,17,20,2b', os: ubuntu-22.04, compiler: clang-14,
               targets: 'libs/unordered/test//cfoa_tests', thread-sanitize: yes, 
-              stdlib: libc++, install: 'clang-14 libc++-14-dev libc++abi-14-dev' }
+              stdlib: libc++, install: 'clang-14 libc++-14-dev libc++abi-14-dev', ccache_key: "tsan" }
+
+          - { compiler: clang-15,  cxxstd: '03,11,14,17,20,2b', os: ubuntu-22.04, stdlib: libc++, install: 'clang-15 libc++-15-dev libc++abi-15-dev' }
 
           # OSX, clang
-          - { compiler: clang,     cxxstd: '03,11,14,17,2a',    os: macos-11, }
-          - { compiler: clang,     cxxstd: '03,11,14,17,2a',    os: macos-12, sanitize: yes }
-          - { compiler: clang,     cxxstd: '11,14,17,2a',       os: macos-12, thread-sanitize: yes, targets: 'libs/unordered/test//cfoa_tests' }
+          - { compiler: clang,     cxxstd: '03,11,14,17,2a',    os: macos-11 }
+          - { compiler: clang,     cxxstd: '03,11,14,17,2a',    os: macos-12, sanitize: yes, ccache_key: "san1" }
+          - { compiler: clang,     cxxstd: '11,14,17,2a',       os: macos-12, thread-sanitize: yes, targets: 'libs/unordered/test//cfoa_tests', ccache_key: "tsan" }
+          - { compiler: clang,     cxxstd: '03,11,14,17,20,2b', os: macos-13 }
 
-    timeout-minutes: 180
+    timeout-minutes: 210
     runs-on: ${{matrix.os}}
     container: ${{matrix.container}}
     env: {B2_USE_CCACHE: 1}