diff --git a/go/purl/ecosystems_simple.go b/go/purl/ecosystems_simple.go
index f9fb845851a..c2258a9f4b2 100644
--- a/go/purl/ecosystems_simple.go
+++ b/go/purl/ecosystems_simple.go
@@ -1,6 +1,8 @@
 package purl
 
 import (
+	"strings"
+
 	"github.com/ossf/osv-schema/bindings/go/osvconstants"
 	"github.com/package-url/packageurl-go"
 )
@@ -16,6 +18,24 @@ func (g simpleGenerator) generate(_, packageName string) (packageurl.PackageURL,
 	return *packageurl.NewPackageURL(g.purlType, g.namespace, packageName, "", g.qualifiers, ""), nil
 }
 
+// slashGenerator handles PURL mappings where the package name contains a slash-separated namespace.
+type slashGenerator struct {
+	purlType   string
+	qualifiers packageurl.Qualifiers
+}
+
+func (g slashGenerator) generate(_, packageName string) (packageurl.PackageURL, error) {
+	namespace := ""
+	name := packageName
+	if strings.Contains(packageName, "/") {
+		parts := strings.Split(packageName, "/")
+		name = parts[len(parts)-1]
+		namespace = strings.Join(parts[:len(parts)-1], "/")
+	}
+
+	return *packageurl.NewPackageURL(g.purlType, namespace, name, "", g.qualifiers, ""), nil
+}
+
 // simpleParser handles standard PURL mappings without special logic.
 type simpleParser struct {
 	ecosystem     osvconstants.Ecosystem
@@ -36,6 +56,11 @@ func registerSimple(ecosystem osvconstants.Ecosystem, purlType string, namespace
 	registerParser(purlType, namespace, simpleParser{ecosystem: ecosystem})
 }
 
+func registerSlash(ecosystem osvconstants.Ecosystem, purlType string) {
+	registerGenerator(ecosystem, slashGenerator{purlType: purlType})
+	registerParser(purlType, "", simpleParser{ecosystem: ecosystem, joinNamespace: true})
+}
+
 //nolint:gochecknoinits // init is used here to register simple ecosystems with the global PURL registry.
 func init() {
 	// Language Ecosystems (No namespace)
@@ -44,18 +69,17 @@ func init() {
 	registerSimple(osvconstants.EcosystemConanCenter, "conan", "", nil)
 	registerSimple(osvconstants.EcosystemDockerHardenedImages, "dhi", "", nil)
 	registerSimple(osvconstants.EcosystemHackage, "hackage", "", nil)
-	registerSimple(osvconstants.EcosystemHex, "hex", "", nil)
+	registerSlash(osvconstants.EcosystemHex, "hex")
 	registerSimple(osvconstants.EcosystemJulia, "julia", "", nil)
 	registerSimple(osvconstants.EcosystemNuGet, "nuget", "", nil)
 	registerSimple(osvconstants.EcosystemOSSFuzz, "generic", "", nil)
-	registerSimple(osvconstants.EcosystemPackagist, "composer", "", nil)
+	registerSlash(osvconstants.EcosystemPackagist, "composer")
 	registerSimple(osvconstants.EcosystemPub, "pub", "", nil)
 	registerSimple(osvconstants.EcosystemPyPI, "pypi", "", nil)
 	registerSimple(osvconstants.EcosystemRubyGems, "gem", "", nil)
-	registerSimple(osvconstants.EcosystemSwiftURL, "swift", "", nil)
+	registerSlash(osvconstants.EcosystemSwiftURL, "swift")
 	registerSimple(osvconstants.EcosystemCratesIO, "cargo", "", nil)
-	registerGenerator(osvconstants.EcosystemNPM, simpleGenerator{purlType: "npm"})
-	registerParser("npm", "", simpleParser{ecosystem: osvconstants.EcosystemNPM, joinNamespace: true})
+	registerSlash(osvconstants.EcosystemNPM, "npm")
 	registerSimple(osvconstants.EcosystemOpam, "opam", "", nil)
 
 	// OS Ecosystems (With static namespace)
diff --git a/go/purl/purl_test.go b/go/purl/purl_test.go
index 7dece1fe472..f7f5d248a91 100644
--- a/go/purl/purl_test.go
+++ b/go/purl/purl_test.go
@@ -21,6 +21,10 @@ func TestGenerate(t *testing.T) {
 		{"Go", "github.com/gorilla/mux", "pkg:golang/github.com/gorilla/mux", false},
 		{"Go", "stdlib", "pkg:golang/stdlib", false},
 		{"Maven", "org.apache.commons:commons-lang3", "pkg:maven/org.apache.commons/commons-lang3", false},
+		{"Packagist", "drupal/colorbox", "pkg:composer/drupal/colorbox", false},
+		{"npm", "@babel/core", "pkg:npm/%40babel/core", false},
+		{"Hex", "acme/foo", "pkg:hex/acme/foo", false},
+		{"SwiftURL", "github.com/apple/swift-markdown", "pkg:swift/github.com/apple/swift-markdown", false},
 		// Error cases
 		{"UnknownEcosystem", "package", "", true},
 	}
@@ -58,6 +62,10 @@ func TestParse(t *testing.T) {
 		{"pkg:golang/stdlib@1.18", "Go", "stdlib", "1.18", false},
 		{"pkg:maven/org.apache.commons/commons-lang3@3.12.0", "Maven", "org.apache.commons:commons-lang3", "3.12.0", false},
 		{"pkg:gradle/org.apache.commons/commons-lang3@3.12.0", "Maven", "org.apache.commons:commons-lang3", "3.12.0", false}, // alias
+		{"pkg:composer/drupal/colorbox@1.2.3", "Packagist", "drupal/colorbox", "1.2.3", false},
+		{"pkg:npm/%40babel/core@1.2.3", "npm", "@babel/core", "1.2.3", false},
+		{"pkg:hex/acme/foo@1.2.3", "Hex", "acme/foo", "1.2.3", false},
+		{"pkg:swift/github.com/apple/swift-markdown@1.2.3", "SwiftURL", "github.com/apple/swift-markdown", "1.2.3", false},
 		// Error cases
 		{"invalid-purl", "", "", "", true},
 		{"pkg:unknown/package@1.0.0", "", "", "", true},