diff --git a/repos/spack_repo/builtin/packages/glx/package.py b/repos/spack_repo/builtin/packages/glx/package.py
index 0caaf0646d9..bd161ea7d7a 100644
--- a/repos/spack_repo/builtin/packages/glx/package.py
+++ b/repos/spack_repo/builtin/packages/glx/package.py
@@ -14,9 +14,18 @@ class Glx(BundlePackage):
 
     version("1.4")
 
+    # GLX is only supported on Linux-like platforms
+    conflicts("platform=windows")
+    conflicts("platform=darwin")
+
     depends_on("libglx")
     provides("gl@4.5")
 
+    def setup_dependent_build_environment(
+        self, env: EnvironmentModifications, dependent_spec: Spec
+    ):
+        env.prepend_path("OpenGL_ROOT", self.home)
+
     @property
     def home(self):
         return self.spec["libglx"].home
diff --git a/repos/spack_repo/builtin/packages/libxslt/package.py b/repos/spack_repo/builtin/packages/libxslt/package.py
index 210731d0b0c..ee95e0c6904 100644
--- a/repos/spack_repo/builtin/packages/libxslt/package.py
+++ b/repos/spack_repo/builtin/packages/libxslt/package.py
@@ -2,12 +2,13 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack_repo.builtin.build_systems.autotools import AutotoolsPackage
+from spack_repo.builtin.build_systems.autotools import AutotoolsBuilder, AutotoolsPackage
+from spack_repo.builtin.build_systems.cmake import CMakeBuilder, CMakePackage
 
 from spack.package import *
 
 
-class Libxslt(AutotoolsPackage):
+class Libxslt(CMakePackage, AutotoolsPackage):
     """Libxslt is the XSLT C library developed for the GNOME project. XSLT
     itself is a an XML language to define transformation for XML. Libxslt is
     based on libxml2 the XML C library developed for the GNOME project. It also
@@ -22,6 +23,8 @@ class Libxslt(AutotoolsPackage):
 
     license("X11", checked_by="wdconinc")
 
+    build_system(conditional("cmake", when="@1.1.35:"), "autotools", default="cmake")
+
     version("1.1.42", sha256="85ca62cac0d41fc77d3f6033da9df6fd73d20ea2fc18b0a3609ffb4110e1baeb")
     version("1.1.41", sha256="3ad392af91115b7740f7b50d228cc1c5fc13afc1da7f16cb0213917a37f71bda")
     version("1.1.40", sha256="194715db023035f65fb566402f2ad2b5eab4c29d541f511305c40b29b1f48d13")
@@ -48,7 +51,9 @@ class Libxslt(AutotoolsPackage):
     depends_on("libxml2+python", when="+python")
     depends_on("xz")
     depends_on("zlib-api")
+
     depends_on("libgcrypt", when="+crypto")
+    conflicts("+crypto", when="platform=windows")
 
     depends_on("python+shared", when="+python")
     extends("python", when="+python")
@@ -59,6 +64,20 @@ def url_for_version(self, v):
         else:
             return f"http://xmlsoft.org/sources/libxslt-{v}.tar.gz"
 
+    @run_after("install")
+    @on_package_attributes(run_tests=True)
+    def import_module_test(self):
+        if self.spec.satisfies("+python"):
+            with working_dir("spack-test", create=True):
+                python("-c", "import libxslt")
+
+    def patch(self):
+        # Remove flags not recognized by the NVIDIA compiler
+        if self.spec.satisfies("build_system=autotools %nvhpc"):
+            filter_file("-Wmissing-format-attribute", "", "configure")
+
+
+class AutotoolsBuilder(AutotoolsBuilder):
     def configure_args(self):
         args = []
 
@@ -74,14 +93,12 @@ def configure_args(self):
 
         return args
 
-    @run_after("install")
-    @on_package_attributes(run_tests=True)
-    def import_module_test(self):
-        if self.spec.satisfies("+python"):
-            with working_dir("spack-test", create=True):
-                python("-c", "import libxslt")
 
-    def patch(self):
-        # Remove flags not recognized by the NVIDIA compiler
-        if self.spec.satisfies("%nvhpc"):
-            filter_file("-Wmissing-format-attribute", "", "configure")
+class CMakeBuilder(CMakeBuilder):
+    def cmake_args(self):
+        return [
+            self.define_from_variant("LIBXSLT_WITH_PYTHON", "python"),
+            self.define_from_variant("LIBXSLT_WITH_CRYPTO", "crypto"),
+            self.define("LIBXSLT_WITH_MODULES", False),
+            self.define("LIBXSLT_WITH_TESTS", False),
+        ]