diff --git a/cmake/FindLLVM.cmake b/cmake/FindLLVM.cmake
index d3c63dde3..03cdd9d3e 100644
--- a/cmake/FindLLVM.cmake
+++ b/cmake/FindLLVM.cmake
@@ -12,17 +12,9 @@ if (NOT LLVM_FOUND)
   find_package(LLVM 12 QUIET CONFIG)
 endif()
 
-if (NOT LLVM_FOUND)
-  find_package(LLVM 11.1 QUIET CONFIG)
-endif()
-
-if (NOT LLVM_FOUND)
-  find_package(LLVM 11 REQUIRED CONFIG)
-endif()
-
 message(STATUS "Found LLVM ${LLVM_PACKAGE_VERSION}")
-if (${LLVM_PACKAGE_VERSION} VERSION_LESS 11)
-  message(FATAL_ERROR "LLVM 11 or newer is required")
+if (${LLVM_PACKAGE_VERSION} VERSION_LESS 12)
+  message(FATAL_ERROR "LLVM 12 or newer is required")
 endif()
 
 find_program(OPT opt
diff --git a/cmake/LLVMKompilePrelude.cmake b/cmake/LLVMKompilePrelude.cmake
index 866cb9ccf..bf096312a 100644
--- a/cmake/LLVMKompilePrelude.cmake
+++ b/cmake/LLVMKompilePrelude.cmake
@@ -2,23 +2,19 @@ find_program(CMAKE_C_COMPILER clang-15)
 find_program(CMAKE_C_COMPILER clang-14)
 find_program(CMAKE_C_COMPILER clang-13)
 find_program(CMAKE_C_COMPILER clang-12)
-find_program(CMAKE_C_COMPILER clang-11)
 find_program(CMAKE_C_COMPILER clang)
 find_program(CMAKE_CXX_COMPILER clang++-15)
 find_program(CMAKE_CXX_COMPILER clang++-14)
 find_program(CMAKE_CXX_COMPILER clang++-13)
 find_program(CMAKE_CXX_COMPILER clang++-12)
-find_program(CMAKE_CXX_COMPILER clang++-11)
 find_program(CMAKE_CXX_COMPILER clang++)
 find_program(CMAKE_C_COMPILER_AR llvm-ar-15)
 find_program(CMAKE_C_COMPILER_AR llvm-ar-14)
 find_program(CMAKE_C_COMPILER_AR llvm-ar-13)
 find_program(CMAKE_C_COMPILER_AR llvm-ar-12)
-find_program(CMAKE_C_COMPILER_AR llvm-ar-11)
 find_program(CMAKE_C_COMPILER_AR llvm-ar)
 find_program(CMAKE_C_COMPILER_RANLIB llvm-ranlib-15)
 find_program(CMAKE_C_COMPILER_RANLIB llvm-ranlib-14)
 find_program(CMAKE_C_COMPILER_RANLIB llvm-ranlib-13)
 find_program(CMAKE_C_COMPILER_RANLIB llvm-ranlib-12)
-find_program(CMAKE_C_COMPILER_RANLIB llvm-ranlib-11)
 find_program(CMAKE_C_COMPILER_RANLIB llvm-ranlib)
diff --git a/flake.nix b/flake.nix
index 909157f6b..c57fc4c4c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -97,7 +97,7 @@
           builtins.listToAttrs (lib.imap0 (i: v: { name = "check_${toString i}"; value = v; }) checks);
 
         matrix = builtins.listToAttrs (lib.forEach (lib.cartesianProductOfSets {
-          llvm-version = [11 12 13 14 15];
+          llvm-version = [12 13 14 15];
           build-type = ["Debug" "Release" "RelWithDebInfo" "FastBuild" "GcStats"];
         }) (
           args:
@@ -117,26 +117,10 @@
         };
         checks = listToChecks [
           # Check that the backend compiles on each supported version of LLVM,
-          # but don't run the test suite on all 15 configurations.
-          llvm-backend-11-FastBuild.llvm-backend
-
-          # Disable the full set temporarily while the checks run on a hosted
-          # runner.
-          # llvm-backend-12-Debug.llvm-backend
+          # but don't run the test suite on all possible configurations.
           llvm-backend-12-FastBuild.llvm-backend
-
-          # llvm-backend-13-Debug.llvm-backend
           llvm-backend-13-FastBuild.llvm-backend
-
-          # llvm-backend-14-Debug.integration-tests
-          # llvm-backend-14-Release.integration-tests
-
-          # llvm-backend-14-RelWithDebInfo.integration-tests
-          # llvm-backend-14-FastBuild.integration-tests
-          # llvm-backend-14-GcStats.integration-tests
-
           llvm-backend-14-FastBuild.llvm-backend
-
           llvm-backend-15-FastBuild.integration-tests
         ];
         devShells.default = llvm-backend-15-FastBuild.devShell;