diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index bfc26f9..89d8ff8 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "2.2.0"
+  ".": "2.2.1"
 }
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6a9b04c..a6dad13 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 # Changelog
 
+## 2.2.1 (2026-02-18)
+
+Full Changelog: [v2.2.0...v2.2.1](https://github.com/imagekit-developer/imagekit-go/compare/v2.2.0...v2.2.1)
+
+### Bug Fixes
+
+* **encoder:** correctly serialize NullStruct ([c8a223a](https://github.com/imagekit-developer/imagekit-go/commit/c8a223a358428b56cd5f13843928252c58acff90))
+
+
+### Chores
+
+* **internal:** codegen related update ([e1e4755](https://github.com/imagekit-developer/imagekit-go/commit/e1e47559733779920f899cb665b244e431702668))
+* **internal:** codegen related update ([5071176](https://github.com/imagekit-developer/imagekit-go/commit/50711763c0f3bee01b36ab00500db61aa371415b))
+
 ## 2.2.0 (2026-02-02)
 
 Full Changelog: [v2.1.1...v2.2.0](https://github.com/imagekit-developer/imagekit-go/compare/v2.1.1...v2.2.0)
diff --git a/README.md b/README.md
index ffc95e0..57a1c28 100644
--- a/README.md
+++ b/README.md
@@ -59,7 +59,7 @@ Or to pin the version:
 <!-- x-release-please-start-version -->
 
 ```sh
-go get -u 'github.com/imagekit-developer/imagekit-go/v2@v2.2.0'
+go get -u 'github.com/imagekit-developer/imagekit-go/v2@v2.2.1'
 ```
 
 <!-- x-release-please-end -->
diff --git a/go.mod b/go.mod
index f306eb5..eb997d7 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@ module github.com/imagekit-developer/imagekit-go/v2
 go 1.22
 
 require (
-	github.com/standard-webhooks/standard-webhooks/libraries v0.0.0-20260114220421-3f69fd681bb0
+	github.com/standard-webhooks/standard-webhooks/libraries v0.0.0-20260218155026-c54c4d7dd7af
 	github.com/tidwall/gjson v1.18.0
 	github.com/tidwall/sjson v1.2.5
 )
diff --git a/go.sum b/go.sum
index b09e3fe..3d177e9 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,5 @@
-github.com/standard-webhooks/standard-webhooks/libraries v0.0.0-20260114220421-3f69fd681bb0 h1:EZXYkItlI9VXF+3x/VFkP8JKa6ibJVZAMjHGfdjzHC8=
-github.com/standard-webhooks/standard-webhooks/libraries v0.0.0-20260114220421-3f69fd681bb0/go.mod h1:L1MQhA6x4dn9r007T033lsaZMv9EmBAdXyU/+EF40fo=
+github.com/standard-webhooks/standard-webhooks/libraries v0.0.0-20260218155026-c54c4d7dd7af h1:N6tWCzt92IpTWj/jB96BLH4FPkEwL4MzWMOlF69Ra+o=
+github.com/standard-webhooks/standard-webhooks/libraries v0.0.0-20260218155026-c54c4d7dd7af/go.mod h1:L1MQhA6x4dn9r007T033lsaZMv9EmBAdXyU/+EF40fo=
 github.com/tidwall/gjson v1.14.2/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
 github.com/tidwall/gjson v1.18.0 h1:FIDeeyB800efLX89e5a8Y0BNH+LOngJyGrIWxG2FKQY=
 github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
diff --git a/internal/version.go b/internal/version.go
index 0759deb..3d559d4 100644
--- a/internal/version.go
+++ b/internal/version.go
@@ -2,4 +2,4 @@
 
 package internal
 
-const PackageVersion = "2.2.0" // x-release-please-version
+const PackageVersion = "2.2.1" // x-release-please-version
diff --git a/packages/param/encoder.go b/packages/param/encoder.go
index b0410be..631e780 100644
--- a/packages/param/encoder.go
+++ b/packages/param/encoder.go
@@ -83,6 +83,9 @@ func MarshalUnion[T ParamStruct](metadata T, variants ...any) ([]byte, error) {
 		}
 	}
 	if nPresent == 0 || presentIdx == -1 {
+		if metadata.null() {
+			return []byte("null"), nil
+		}
 		if ovr, ok := metadata.Overrides(); ok {
 			return shimjson.Marshal(ovr)
 		}
diff --git a/packages/param/encoder_test.go b/packages/param/encoder_test.go
index a86612f..eed22a0 100644
--- a/packages/param/encoder_test.go
+++ b/packages/param/encoder_test.go
@@ -363,3 +363,15 @@ func TestOverriddenUnion(t *testing.T) {
 		})
 	}
 }
+
+func TestNullStructUnion(t *testing.T) {
+	nullUnion := param.NullStruct[PrimitiveUnion]()
+
+	b, err := json.Marshal(nullUnion)
+	if err != nil {
+		t.Fatalf("didn't expect error %v", err)
+	}
+	if string(b) != "null" {
+		t.Fatalf("expected null, received %s", string(b))
+	}
+}