diff --git a/src/libexpr/flake/url-name.cc b/src/libexpr/flake/url-name.cc
index 7e51aa2e1..753f197d5 100644
--- a/src/libexpr/flake/url-name.cc
+++ b/src/libexpr/flake/url-name.cc
@@ -4,7 +4,7 @@
 
 namespace nix {
 
-static const std::string attributeNamePattern("[a-z0-9_-]+");
+static const std::string attributeNamePattern("[a-zA-Z0-9_-]+");
 static const std::regex lastAttributeRegex("(?:" + attributeNamePattern + "\\.)*(?!default)(" + attributeNamePattern +")(\\^.*)?");
 static const std::string pathSegmentPattern("[a-zA-Z0-9_-]+");
 static const std::regex lastPathSegmentRegex(".*/(" + pathSegmentPattern +")");
diff --git a/tests/unit/libexpr/flake/url-name.cc b/tests/unit/libexpr/flake/url-name.cc
index 84d32837c..85387b323 100644
--- a/tests/unit/libexpr/flake/url-name.cc
+++ b/tests/unit/libexpr/flake/url-name.cc
@@ -5,11 +5,13 @@ namespace nix {
 
 /* ----------- tests for url-name.hh --------------------------------------------------*/
 
-    TEST(getNameFromURL, getsNameFromURL) {
+    TEST(getNameFromURL, getNameFromURL) {
         ASSERT_EQ(getNameFromURL(parseURL("path:/home/user/project")), "project");
         ASSERT_EQ(getNameFromURL(parseURL("path:~/repos/nixpkgs#packages.x86_64-linux.hello")), "hello");
-        ASSERT_EQ(getNameFromURL(parseURL("path:.#nonStandardAttr.mylaptop")), "nonStandardAttr.mylaptop");
-        ASSERT_EQ(getNameFromURL(parseURL("path:./repos/myflake#nonStandardAttr.mylaptop")), "nonStandardAttr.mylaptop");
+        ASSERT_EQ(getNameFromURL(parseURL("path:~/repos/nixpkgs#legacyPackages.x86_64-linux.hello")), "hello");
+        ASSERT_EQ(getNameFromURL(parseURL("path:~/repos/nixpkgs#packages.x86_64-linux.Hello")), "Hello");
+        ASSERT_EQ(getNameFromURL(parseURL("path:.#nonStandardAttr.mylaptop")), "mylaptop");
+        ASSERT_EQ(getNameFromURL(parseURL("path:./repos/myflake#nonStandardAttr.mylaptop")), "mylaptop");
         ASSERT_EQ(getNameFromURL(parseURL("path:./nixpkgs#packages.x86_64-linux.complex^bin,man")), "complex");
         ASSERT_EQ(getNameFromURL(parseURL("path:./myproj#packages.x86_64-linux.default^*")), "myproj");