diff --git a/packages/tendermint-rpc/src/tendermint34/adaptor/responses.ts b/packages/tendermint-rpc/src/tendermint34/adaptor/responses.ts
index 85613bafc2..1a44a10e15 100644
--- a/packages/tendermint-rpc/src/tendermint34/adaptor/responses.ts
+++ b/packages/tendermint-rpc/src/tendermint34/adaptor/responses.ts
@@ -17,7 +17,6 @@ import {
   dictionaryToStringMap,
   Integer,
   may,
-  optional,
 } from "../encodings";
 import { hashTx } from "../hasher";
 import * as responses from "../responses";
@@ -110,13 +109,13 @@ interface RpcAttribute {
   /** base64 encoded */
   readonly key: string;
   /** base64 encoded */
-  readonly value: string;
+  readonly value?: string | null;
 }
 
 function decodeAttribute(attribute: RpcAttribute): responses.Attribute {
   return {
     key: fromBase64(assertNotEmpty(attribute.key)),
-    value: fromBase64(optional(attribute.value, "")),
+    value: fromBase64(assertString(attribute.value ?? "")),
   };
 }
 
@@ -154,13 +153,13 @@ interface RpcTxData {
 
 function decodeTxData(data: RpcTxData): responses.TxData {
   return {
-    code: Integer.parse(assertNumber(optional<number>(data.code, 0))),
+    code: Integer.parse(assertNumber(data.code ?? 0)),
     codeSpace: data.codespace,
     log: data.log,
     data: may(fromBase64, data.data),
     events: data.events ? decodeEvents(data.events) : [],
-    gasWanted: Integer.parse(optional<string>(data.gas_wanted, "0")),
-    gasUsed: Integer.parse(optional<string>(data.gas_used, "0")),
+    gasWanted: Integer.parse(data.gas_wanted ?? "0"),
+    gasUsed: Integer.parse(data.gas_used ?? "0"),
   };
 }
 
diff --git a/packages/tendermint-rpc/src/tendermint34/encodings.ts b/packages/tendermint-rpc/src/tendermint34/encodings.ts
index bbdcfc2aa5..ec5b072775 100644
--- a/packages/tendermint-rpc/src/tendermint34/encodings.ts
+++ b/packages/tendermint-rpc/src/tendermint34/encodings.ts
@@ -123,11 +123,6 @@ export function assertNotEmpty<T>(value: T): T {
   return value;
 }
 
-// optional uses the value or provides a default
-export function optional<T>(value: T | null | undefined, fallback: T): T {
-  return value === undefined || value === null ? fallback : value;
-}
-
 // may will run the transform if value is defined, otherwise returns undefined
 export function may<T, U>(transform: (val: T) => U, value: T | null | undefined): U | undefined {
   return value === undefined || value === null ? undefined : transform(value);
diff --git a/packages/tendermint-rpc/src/tendermint35/adaptor/responses.ts b/packages/tendermint-rpc/src/tendermint35/adaptor/responses.ts
index 0aab89cc64..811f113520 100644
--- a/packages/tendermint-rpc/src/tendermint35/adaptor/responses.ts
+++ b/packages/tendermint-rpc/src/tendermint35/adaptor/responses.ts
@@ -17,7 +17,6 @@ import {
   dictionaryToStringMap,
   Integer,
   may,
-  optional,
 } from "../encodings";
 import { hashTx } from "../hasher";
 import * as responses from "../responses";
@@ -111,13 +110,13 @@ function decodeAbciQuery(data: RpcAbciQueryResponse): responses.AbciQueryRespons
  */
 interface RpcEventAttribute {
   readonly key: string;
-  readonly value: string;
+  readonly value?: string;
 }
 
 function decodeEventAttribute(attribute: RpcEventAttribute): responses.EventAttribute {
   return {
     key: assertNotEmpty(attribute.key),
-    value: optional(attribute.value, ""),
+    value: attribute.value ?? "",
   };
 }
 
@@ -155,13 +154,13 @@ interface RpcTxData {
 
 function decodeTxData(data: RpcTxData): responses.TxData {
   return {
-    code: Integer.parse(assertNumber(optional<number>(data.code, 0))),
+    code: Integer.parse(assertNumber(data.code ?? 0)),
     codeSpace: data.codespace,
     log: data.log,
     data: may(fromBase64, data.data),
     events: data.events ? decodeEvents(data.events) : [],
-    gasWanted: Integer.parse(optional<string>(data.gas_wanted, "0")),
-    gasUsed: Integer.parse(optional<string>(data.gas_used, "0")),
+    gasWanted: Integer.parse(data.gas_wanted ?? "0"),
+    gasUsed: Integer.parse(data.gas_used ?? "0"),
   };
 }
 
diff --git a/packages/tendermint-rpc/src/tendermint35/encodings.ts b/packages/tendermint-rpc/src/tendermint35/encodings.ts
index bbdcfc2aa5..ec5b072775 100644
--- a/packages/tendermint-rpc/src/tendermint35/encodings.ts
+++ b/packages/tendermint-rpc/src/tendermint35/encodings.ts
@@ -123,11 +123,6 @@ export function assertNotEmpty<T>(value: T): T {
   return value;
 }
 
-// optional uses the value or provides a default
-export function optional<T>(value: T | null | undefined, fallback: T): T {
-  return value === undefined || value === null ? fallback : value;
-}
-
 // may will run the transform if value is defined, otherwise returns undefined
 export function may<T, U>(transform: (val: T) => U, value: T | null | undefined): U | undefined {
   return value === undefined || value === null ? undefined : transform(value);