diff --git a/integration/before-after-request-streaming/example.ts b/integration/before-after-request-streaming/example.ts
index e884224a8..97b9973b2 100644
--- a/integration/before-after-request-streaming/example.ts
+++ b/integration/before-after-request-streaming/example.ts
@@ -91,7 +91,8 @@ export interface DashAPICredsDeleteReq {
   id: string;
 }
 
-export interface Empty {}
+export interface Empty {
+}
 
 function createBaseDashFlash(): DashFlash {
   return { msg: "", type: 0 };
@@ -250,10 +251,9 @@ export const DashUserSettingsState = {
   fromPartial<I extends Exact<DeepPartial<DashUserSettingsState>, I>>(object: I): DashUserSettingsState {
     const message = createBaseDashUserSettingsState();
     message.email = object.email ?? "";
-    message.urls =
-      object.urls !== undefined && object.urls !== null
-        ? DashUserSettingsState_URLs.fromPartial(object.urls)
-        : undefined;
+    message.urls = (object.urls !== undefined && object.urls !== null)
+      ? DashUserSettingsState_URLs.fromPartial(object.urls)
+      : undefined;
     message.flashes = object.flashes?.map((e) => DashFlash.fromPartial(e)) || [];
     return message;
   },
@@ -756,24 +756,22 @@ export class DashStateClientImpl implements DashState {
       this.rpc.beforeRequest(this.service, "UserSettings", request);
     }
     const promise = this.rpc.request(this.service, "UserSettings", data);
-    return promise
-      .then((data) => {
-        try {
-          const response = DashUserSettingsState.decode(_m0.Reader.create(data));
-          if (this.rpc.afterResponse) {
-            this.rpc.afterResponse(this.service, "UserSettings", response);
-          }
-          return response;
-        } catch (error) {
-          return Promise.reject(error);
-        }
-      })
-      .catch((error) => {
-        if (this.rpc.handleError) {
-          return Promise.reject(this.rpc.handleError(this.service, "UserSettings", error));
+    return promise.then((data) => {
+      try {
+        const response = DashUserSettingsState.decode(_m0.Reader.create(data));
+        if (this.rpc.afterResponse) {
+          this.rpc.afterResponse(this.service, "UserSettings", response);
         }
+        return response;
+      } catch (error) {
         return Promise.reject(error);
-      });
+      }
+    }).catch((error) => {
+      if (this.rpc.handleError) {
+        return Promise.reject(this.rpc.handleError(this.service, "UserSettings", error));
+      }
+      return Promise.reject(error);
+    });
   }
 
   ActiveUserSettingsStream(request: Empty): Observable<DashUserSettingsState> {
@@ -782,37 +780,39 @@ export class DashStateClientImpl implements DashState {
       this.rpc.beforeRequest(this.service, "ActiveUserSettingsStream", request);
     }
     const result = this.rpc.serverStreamingRequest(this.service, "ActiveUserSettingsStream", data);
-    return result.pipe(
-      map((data) => {
+    return result.pipe(map((data) => {
+      try {
         const response = DashUserSettingsState.decode(_m0.Reader.create(data));
         if (this.rpc.afterResponse) {
           this.rpc.afterResponse(this.service, "ActiveUserSettingsStream", response);
         }
         return response;
-      }),
-    );
+      } catch (error) {
+        throw error;
+      }
+    }));
   }
 
   ChangeUserSettingsStream(request: Observable<DashUserSettingsState>): Observable<DashUserSettingsState> {
-    const data = request.pipe(
-      map((request) => {
-        const encodedRequest = DashUserSettingsState.encode(request).finish();
-        if (this.rpc.beforeRequest) {
-          this.rpc.beforeRequest(this.service, "ChangeUserSettingsStream", encodedRequest);
-        }
-        return encodedRequest;
-      }),
-    );
+    const data = request.pipe(map((request) => {
+      const encodedRequest = DashUserSettingsState.encode(request).finish();
+      if (this.rpc.beforeRequest) {
+        this.rpc.beforeRequest(this.service, "ChangeUserSettingsStream", encodedRequest);
+      }
+      return encodedRequest;
+    }));
     const result = this.rpc.bidirectionalStreamingRequest(this.service, "ChangeUserSettingsStream", data);
-    return result.pipe(
-      map((data) => {
+    return result.pipe(map((data) => {
+      try {
         const response = DashUserSettingsState.decode(_m0.Reader.create(data));
         if (this.rpc.afterResponse) {
           this.rpc.afterResponse(this.service, "ChangeUserSettingsStream", response);
         }
         return response;
-      }),
-    );
+      } catch (error) {
+        throw error;
+      }
+    }));
   }
 }
 
@@ -879,24 +879,22 @@ export class DashAPICredsClientImpl implements DashAPICreds {
       this.rpc.beforeRequest(this.service, "Create", request);
     }
     const promise = this.rpc.request(this.service, "Create", data);
-    return promise
-      .then((data) => {
-        try {
-          const response = DashCred.decode(_m0.Reader.create(data));
-          if (this.rpc.afterResponse) {
-            this.rpc.afterResponse(this.service, "Create", response);
-          }
-          return response;
-        } catch (error) {
-          return Promise.reject(error);
-        }
-      })
-      .catch((error) => {
-        if (this.rpc.handleError) {
-          return Promise.reject(this.rpc.handleError(this.service, "Create", error));
+    return promise.then((data) => {
+      try {
+        const response = DashCred.decode(_m0.Reader.create(data));
+        if (this.rpc.afterResponse) {
+          this.rpc.afterResponse(this.service, "Create", response);
         }
+        return response;
+      } catch (error) {
         return Promise.reject(error);
-      });
+      }
+    }).catch((error) => {
+      if (this.rpc.handleError) {
+        return Promise.reject(this.rpc.handleError(this.service, "Create", error));
+      }
+      return Promise.reject(error);
+    });
   }
 
   Update(request: DashAPICredsUpdateReq): Promise<DashCred> {
@@ -905,24 +903,22 @@ export class DashAPICredsClientImpl implements DashAPICreds {
       this.rpc.beforeRequest(this.service, "Update", request);
     }
     const promise = this.rpc.request(this.service, "Update", data);
-    return promise
-      .then((data) => {
-        try {
-          const response = DashCred.decode(_m0.Reader.create(data));
-          if (this.rpc.afterResponse) {
-            this.rpc.afterResponse(this.service, "Update", response);
-          }
-          return response;
-        } catch (error) {
-          return Promise.reject(error);
-        }
-      })
-      .catch((error) => {
-        if (this.rpc.handleError) {
-          return Promise.reject(this.rpc.handleError(this.service, "Update", error));
+    return promise.then((data) => {
+      try {
+        const response = DashCred.decode(_m0.Reader.create(data));
+        if (this.rpc.afterResponse) {
+          this.rpc.afterResponse(this.service, "Update", response);
         }
+        return response;
+      } catch (error) {
         return Promise.reject(error);
-      });
+      }
+    }).catch((error) => {
+      if (this.rpc.handleError) {
+        return Promise.reject(this.rpc.handleError(this.service, "Update", error));
+      }
+      return Promise.reject(error);
+    });
   }
 
   Delete(request: DashAPICredsDeleteReq): Promise<DashCred> {
@@ -931,24 +927,22 @@ export class DashAPICredsClientImpl implements DashAPICreds {
       this.rpc.beforeRequest(this.service, "Delete", request);
     }
     const promise = this.rpc.request(this.service, "Delete", data);
-    return promise
-      .then((data) => {
-        try {
-          const response = DashCred.decode(_m0.Reader.create(data));
-          if (this.rpc.afterResponse) {
-            this.rpc.afterResponse(this.service, "Delete", response);
-          }
-          return response;
-        } catch (error) {
-          return Promise.reject(error);
-        }
-      })
-      .catch((error) => {
-        if (this.rpc.handleError) {
-          return Promise.reject(this.rpc.handleError(this.service, "Delete", error));
+    return promise.then((data) => {
+      try {
+        const response = DashCred.decode(_m0.Reader.create(data));
+        if (this.rpc.afterResponse) {
+          this.rpc.afterResponse(this.service, "Delete", response);
         }
+        return response;
+      } catch (error) {
         return Promise.reject(error);
-      });
+      }
+    }).catch((error) => {
+      if (this.rpc.handleError) {
+        return Promise.reject(this.rpc.handleError(this.service, "Delete", error));
+      }
+      return Promise.reject(error);
+    });
   }
 
   Uppercase(request: StringValue): Promise<StringValue> {
@@ -957,24 +951,22 @@ export class DashAPICredsClientImpl implements DashAPICreds {
       this.rpc.beforeRequest(this.service, "Uppercase", request);
     }
     const promise = this.rpc.request(this.service, "Uppercase", data);
-    return promise
-      .then((data) => {
-        try {
-          const response = StringValue.decode(_m0.Reader.create(data));
-          if (this.rpc.afterResponse) {
-            this.rpc.afterResponse(this.service, "Uppercase", response);
-          }
-          return response;
-        } catch (error) {
-          return Promise.reject(error);
-        }
-      })
-      .catch((error) => {
-        if (this.rpc.handleError) {
-          return Promise.reject(this.rpc.handleError(this.service, "Uppercase", error));
+    return promise.then((data) => {
+      try {
+        const response = StringValue.decode(_m0.Reader.create(data));
+        if (this.rpc.afterResponse) {
+          this.rpc.afterResponse(this.service, "Uppercase", response);
         }
+        return response;
+      } catch (error) {
         return Promise.reject(error);
-      });
+      }
+    }).catch((error) => {
+      if (this.rpc.handleError) {
+        return Promise.reject(this.rpc.handleError(this.service, "Uppercase", error));
+      }
+      return Promise.reject(error);
+    });
   }
 }
 
@@ -1035,19 +1027,14 @@ interface Rpc {
 
 type Builtin = Date | Function | Uint8Array | string | number | boolean | undefined;
 
-export type DeepPartial<T> = T extends Builtin
-  ? T
-  : T extends globalThis.Array<infer U>
-  ? globalThis.Array<DeepPartial<U>>
-  : T extends ReadonlyArray<infer U>
-  ? ReadonlyArray<DeepPartial<U>>
-  : T extends {}
-  ? { [K in keyof T]?: DeepPartial<T[K]> }
+export type DeepPartial<T> = T extends Builtin ? T
+  : T extends globalThis.Array<infer U> ? globalThis.Array<DeepPartial<U>>
+  : T extends ReadonlyArray<infer U> ? ReadonlyArray<DeepPartial<U>>
+  : T extends {} ? { [K in keyof T]?: DeepPartial<T[K]> }
   : Partial<T>;
 
 type KeysOfUnion<T> = T extends T ? keyof T : never;
-export type Exact<P, I extends P> = P extends Builtin
-  ? P
+export type Exact<P, I extends P> = P extends Builtin ? P
   : P & { [K in keyof P]: Exact<P[K], I[K]> } & { [K in Exclude<keyof I, KeysOfUnion<P>>]: never };
 
 function isSet(value: any): boolean {
diff --git a/src/generate-services.ts b/src/generate-services.ts
index 924c33532..42fca4402 100644
--- a/src/generate-services.ts
+++ b/src/generate-services.ts
@@ -10,6 +10,7 @@ import {
   observableType,
 } from "./types";
 import {
+  arrowFunction,
   assertInstanceOf,
   FormattedMethodDescriptor,
   impFile,
@@ -214,27 +215,29 @@ function createDefaultServiceReturn(
 ): Code {
   const { options } = ctx;
   const rawOutputType = responseType(ctx, methodDesc, { keepValueType: true });
-  let returnStatement = code`data => ${decode}`;
-  if (options.rpcAfterResponse) {
-    returnStatement = code`data => { ${decode} }`;
-  }
+  const returnStatement = arrowFunction("data", decode, !options.rpcAfterResponse);
+
   if (options.returnObservable || methodDesc.serverStreaming) {
     if (options.useAsyncIterable) {
       return code`${rawOutputType}.decodeTransform(result)`;
     } else {
+      if (errorHandler) {
+        const tc = arrowFunction("data", tryCatchBlock(decode, code`throw error`), !options.rpcAfterResponse);
+        return code`result.pipe(${imp("map@rxjs/operators")}(${tc}))`;
+      }
       return code`result.pipe(${imp("map@rxjs/operators")}(${returnStatement}))`;
     }
   }
 
   if (errorHandler) {
-    let tryBlock = decode;
     if (!options.rpcAfterResponse) {
-      tryBlock = code`return ${decode}`;
+      decode = code`return ${decode}`;
     }
-    return code`promise.then(data => { ${tryCatchBlock(
-      tryBlock,
-      code`return Promise.reject(error);`,
-    )}}).catch((error) => { ${errorHandler} })`;
+    return code`promise.then(${arrowFunction(
+      "data",
+      tryCatchBlock(decode, code`return Promise.reject(error);`),
+      false,
+    )}).catch(${arrowFunction("error", errorHandler, false)})`;
   }
   return code`promise.then(${returnStatement})`;
 }
diff --git a/src/utils.ts b/src/utils.ts
index b36c89e86..9983c8f9e 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -296,3 +296,10 @@ export function tryCatchBlock(tryBlock: Code | string, handleErrorBlock: Code |
     ${handleErrorBlock}
   }`;
 }
+
+export function arrowFunction(params: string, body: Code | string, isOneLine: boolean = true): Code {
+  if (isOneLine) {
+    return code`(${params}) => ${body}`;
+  }
+  return code`(${params}) => { ${body} }`;
+}