diff --git a/umbral-pre-wasm/Makefile b/umbral-pre-wasm/Makefile
index 08cd06dc..b53dc577 100644
--- a/umbral-pre-wasm/Makefile
+++ b/umbral-pre-wasm/Makefile
@@ -23,6 +23,9 @@ pkg: src
 	cp package.template.json pkg/package.json
 	cp LICENSE README.md pkg/
 
+	# add patches
+	cat ./patches/api-compatibility.js.txt >> pkg/pkg-bundler/umbral_pre_wasm.js
+
 
 .PHONY: clean
 
diff --git a/umbral-pre-wasm/patches/api-compatibility.js.txt b/umbral-pre-wasm/patches/api-compatibility.js.txt
new file mode 100644
index 00000000..43ae43d3
--- /dev/null
+++ b/umbral-pre-wasm/patches/api-compatibility.js.txt
@@ -0,0 +1,48 @@
+
+/*
+    contents added by umbral-pre-wasm makefile/build script
+*/
+
+import { KeyFrag, encryptPlaintext } from  "./umbral_pre_wasm_bg.js";
+
+export const decrypt_reencrypted = (
+    receiving_sk,//: SecretKey,
+    delegating_pk,//: PublicKey,
+    capsule,//: Capsule,
+    verified_cfrags,//: Sequence[VerifiedCapsuleFrag],
+    ciphertext//: bytes,) => (
+) => {
+    const capsuleWithCFrags = verified_cfrags.reduce((value, cfrag) => {
+        return value.withCFrag(cfrag)
+    }, capsule)
+    return capsuleWithCFrags.decryptReencrypted(receiving_sk, delegating_pk, ciphertext);
+}
+
+export function encrypt(delegating_pk, plaintext) {
+    const encryptionResult = encryptPlaintext(delegating_pk, plaintext)
+    return {
+        capsule: encryptionResult.capsule,
+        ciphertext: encryptionResult.ciphertext
+    }
+}
+
+KeyFrag.prototype.verify =  (verifying_pk, optional = {delegating_pk, receiving_pk} = {}) => {
+    const delegating_pk = optional.delegating_pk
+    const receiving_pk = optional.receiving_pk
+
+    if (receiving_pk && delegating_pk) {
+        return this.verifyWithDelegatingAndReceivingKeys(verifying_pk, delegating_pk, receiving_pk)
+    }
+
+    if (receiving_pk){
+        return this.verifyWithReceivingKey(verifying_pk, receiving_pk)
+    }
+
+    if (delegating_pk){
+        return this.verifyWithDelegatingKey(verifying_pk, delegating_pk)
+    }
+
+    return this.verify_with_only_public_key()
+}
+
+
diff --git a/umbral-pre-wasm/src/lib.rs b/umbral-pre-wasm/src/lib.rs
index cd4d1e9c..bf818eab 100644
--- a/umbral-pre-wasm/src/lib.rs
+++ b/umbral-pre-wasm/src/lib.rs
@@ -393,7 +393,7 @@ impl KeyFrag {
     // So we have to use 4 functions instead of 1. Yikes.
 
     #[wasm_bindgen]
-    pub fn verify(&self, verifying_pk: &PublicKey) -> Result<VerifiedKeyFrag, JsValue> {
+    pub fn verify_with_only_public_key(&self, verifying_pk: &PublicKey) -> Result<VerifiedKeyFrag, JsValue> {
         self.0
             .verify(&verifying_pk.0, None, None)
             .map(VerifiedKeyFrag)