diff --git a/.drone.jsonnet b/.drone.jsonnet
index 939fe2df..99d793c1 100644
--- a/.drone.jsonnet
+++ b/.drone.jsonnet
@@ -186,14 +186,6 @@ local windows_pipeline(name, image, environment, arch = "amd64") =
         "g++-14-multilib",
     ),
 
-    linux_pipeline(
-        "Linux 22.04 Clang 15",
-        "cppalliance/droneubuntu2204:1",
-        { TOOLSET: 'clang', COMPILER: 'clang++-15', CXXSTD: '03,11,14,17,20,2b' },
-        "clang-15",
-        ["deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-15 main"],
-    ),
-
     linux_pipeline(
         "Linux 22.04 Clang 16",
         "cppalliance/droneubuntu2204:1",
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6083468d..2badeef9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -51,7 +51,6 @@ jobs:
           - { name: GCC w/ sanitizers, sanitize: yes,
               compiler: gcc-13,    cxxstd: '03,11,14,17,20', os: ubuntu-24.04 }
           # Clang isn't compatible with libstdc++-13, so use the slightly older one
-          - { compiler: clang-15,  cxxstd: '03,11,14,17,20', os: ubuntu-22.04, install: 'clang-15 g++-12', gcc_toolchain: 12 }
           - { compiler: clang-16,  cxxstd: '11,14,17,20,2b', os: ubuntu-24.04, install: 'clang-16 g++-12', gcc_toolchain: 12 }
           # https://github.com/llvm/llvm-project/issues/59827: disabled 2b/23 for clang-17 with libstdc++13 in 24.04
           - { compiler: clang-17,  cxxstd: '11,14,17,20',    os: ubuntu-24.04 }
diff --git a/.github/workflows/fuzz.yml b/.github/workflows/fuzz.yml
index f21423e1..780a8251 100644
--- a/.github/workflows/fuzz.yml
+++ b/.github/workflows/fuzz.yml
@@ -32,16 +32,6 @@ jobs:
 
           # Linux, clang
           # https://llvm.org/docs/LibFuzzer.html#fuzzer-usage
-          - toolset: clang
-            compiler: clang++-15
-            cxxstd: "20"
-            os: ubuntu-22.04
-            install:
-              - clang-15
-            sources:
-              - "deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-15 main"
-            source_keys:
-              - "https://apt.llvm.org/llvm-snapshot.gpg.key"
           - toolset: clang
             compiler: clang++-16
             cxxstd: "20"