diff --git a/lib/index.js b/lib/index.js
index 654722f..0d2343b 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -1,7 +1,11 @@
 "use strict";
 var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
-    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
 }) : (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
     o[k2] = m[k];
diff --git a/lib/internal/reference/index.js b/lib/internal/reference/index.js
index 36265a6..9aff76e 100644
--- a/lib/internal/reference/index.js
+++ b/lib/internal/reference/index.js
@@ -1,7 +1,11 @@
 "use strict";
 var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
-    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
 }) : (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
     o[k2] = m[k];
diff --git a/lib/management/index.d.ts b/lib/management/index.d.ts
index a177963..cbd566a 100644
--- a/lib/management/index.d.ts
+++ b/lib/management/index.d.ts
@@ -8,6 +8,7 @@ export declare type Config = {
     readonly storeHash: string;
     readonly accessToken: string;
     readonly agent?: Agent;
+    readonly customHeaders?: Record<string, string>;
 };
 /**
  * If you need to use a path which is not part if the spec, you can pass it
diff --git a/lib/management/index.js b/lib/management/index.js
index f557587..830b8ec 100644
--- a/lib/management/index.js
+++ b/lib/management/index.js
@@ -1,7 +1,11 @@
 "use strict";
 var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
-    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
 }) : (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
     o[k2] = m[k];
diff --git a/lib/management/v2/index.d.ts b/lib/management/v2/index.d.ts
index 67d4e77..9e54117 100644
--- a/lib/management/v2/index.d.ts
+++ b/lib/management/v2/index.d.ts
@@ -12,6 +12,7 @@ export declare type ResponseData<ReqLine extends RequestLine, Params extends Par
 export declare type Config = Omit<FetchTransportOptions, 'baseUrl' | 'headers'> & {
     readonly storeHash: string;
     readonly accessToken: string;
+    readonly customHeaders?: Record<string, string>;
 };
 export declare class Client<CustomEndpoints extends string = never> {
     constructor(config: Config);
diff --git a/lib/management/v2/index.js b/lib/management/v2/index.js
index 2ecf553..f2aa1d9 100644
--- a/lib/management/v2/index.js
+++ b/lib/management/v2/index.js
@@ -10,7 +10,7 @@ class Client {
                 : (0, operation_1.fetchTransport)({
                     agent: configOrTransport.agent,
                     baseUrl: `https://api.bigcommerce.com/stores/${configOrTransport.storeHash}/v2`,
-                    headers: { "X-Auth-Token": configOrTransport.accessToken },
+                    headers: { "X-Auth-Token": configOrTransport.accessToken, ...(configOrTransport.customHeaders || {}) },
                 });
     }
     async send(requestLine, params) {
diff --git a/lib/management/v3/index.d.ts b/lib/management/v3/index.d.ts
index 520d83d..c13f108 100644
--- a/lib/management/v3/index.d.ts
+++ b/lib/management/v3/index.d.ts
@@ -6,7 +6,7 @@ import { RemoveStart } from "../../internal/type-utils";
 export declare type Operations = reference.Operation;
 export declare type RequestLine = keyof Operations;
 export declare type NoParamsRequestLine = keyof OperationIndex.FilterOptionalParams<Operations>;
-export declare type InferResponse<ReqLine extends RequestLine, Params> = NarrowResponse<Operations, Request<ReqLine, Params>, Operations[ReqLine]['response']>;
+export declare type InferResponse<ReqLine extends RequestLine, Params extends Parameters> = NarrowResponse<Operations, Request<ReqLine, Params>, Operations[ReqLine]['response']>;
 export declare type ResponseData<ReqLine extends RequestLine, Params = unknown> = Response.Success<ResolveResponse<ReqLine, Params>> extends {
     readonly body: {
         readonly data?: infer Data;
@@ -15,6 +15,7 @@ export declare type ResponseData<ReqLine extends RequestLine, Params = unknown>
 export declare type Config = Omit<FetchTransportOptions, 'baseUrl' | 'headers'> & {
     readonly storeHash: string;
     readonly accessToken: string;
+    readonly customHeaders?: Record<string, string>;
 };
 export declare class Client<CustomEndpoints extends string = never> {
     constructor(config: Config);
diff --git a/lib/management/v3/index.js b/lib/management/v3/index.js
index facff66..14c9b99 100644
--- a/lib/management/v3/index.js
+++ b/lib/management/v3/index.js
@@ -8,7 +8,7 @@ class Client {
             typeof configOrTransport === 'function'
                 ? configOrTransport
                 : (0, operation_1.fetchTransport)({
-                    headers: { "X-Auth-Token": configOrTransport.accessToken },
+                    headers: { "X-Auth-Token": configOrTransport.accessToken, ...(configOrTransport.customHeaders || {}) },
                     baseUrl: `https://api.bigcommerce.com/stores/${configOrTransport.storeHash}/v3`,
                     agent: configOrTransport.agent,
                 });
diff --git a/lib/storefront/index.d.ts b/lib/storefront/index.d.ts
index a0688be..ff0250e 100644
--- a/lib/storefront/index.d.ts
+++ b/lib/storefront/index.d.ts
@@ -5,20 +5,18 @@ import { Const } from "../internal/type-utils";
 export declare type Operations = reference.Operation;
 export declare type RequestLine = keyof Operations;
 export declare type NoParamsRequestLine = keyof OperationIndex.FilterOptionalParams<Operations>;
-export declare type InferResponse<ReqLine extends RequestLine, Params> = NarrowResponse<Operations, Request<ReqLine, Params>, Operations[ReqLine]['response']>;
+export declare type InferResponse<ReqLine extends RequestLine, Params extends Parameters> = NarrowResponse<Operations, Request<ReqLine, Params>, Operations[ReqLine]['response']>;
 export declare type ResponseData<ReqLine extends RequestLine, Params = unknown> = Response.Success<ResolveResponse<ReqLine, Params>> extends {
     readonly body: infer Data;
 } ? Data : never;
 export interface Client {
     send<ReqLine extends NoParamsRequestLine>(requestLine: ReqLine): Promise<InferResponse<ReqLine, {}>>;
     send<ReqLine extends RequestLine, Params extends Operation.MinimalInput<Operations[ReqLine]>>(requestLine: ReqLine, params: Const<Params & Operation.MinimalInput<Operations[ReqLine]>>): Promise<InferResponse<ReqLine, Params>>;
-    delete<Path extends NoParamsRequestPath<'DELETE'>>(requestLine: Path): Promise<ResponseData<`DELETE ${Path}`, {}> | null>;
     delete<Path extends RequestPath<'DELETE'>, Params extends Operation.MinimalInput<Operations[`DELETE ${Path}`]>>(path: Path, params: Const<Params & Operation.MinimalInput<Operations[`DELETE ${Path}`]>>): Promise<ResponseData<`DELETE ${Path}`, Params> | null>;
     get<Path extends NoParamsRequestPath<'GET'>>(requestLine: Path): Promise<ResponseData<`GET ${Path}`, {}> | null>;
     get<Path extends RequestPath<'GET'>, Params extends Operation.MinimalInput<Operations[`GET ${Path}`]>>(path: Path, params: Const<Params & Operation.MinimalInput<Operations[`GET ${Path}`]>>): Promise<ResponseData<`GET ${Path}`, Params> | null>;
     post<Path extends NoParamsRequestPath<'POST'>>(requestLine: Path): Promise<ResponseData<`POST ${Path}`, {}>>;
     post<Path extends RequestPath<'POST'>, Params extends Operation.MinimalInput<Operations[`POST ${Path}`]>>(path: Path, params: Const<Params & Operation.MinimalInput<Operations[`POST ${Path}`]>>): Promise<ResponseData<`POST ${Path}`, Params>>;
-    put<Path extends NoParamsRequestPath<'PUT'>>(requestLine: Path): Promise<ResponseData<`PUT ${Path}`, {}>>;
     put<Path extends RequestPath<'PUT'>, Params extends Operation.MinimalInput<Operations[`PUT ${Path}`]>>(path: Path, params: Const<Params & Operation.MinimalInput<Operations[`PUT ${Path}`]>>): Promise<ResponseData<`PUT ${Path}`, Params>>;
 }
 declare type ResolveResponse<ReqLine extends RequestLine, Params = unknown> = unknown extends Params ? Operations[ReqLine]['response'] : Params extends Parameters ? InferResponse<ReqLine, Params> : never;
diff --git a/package-lock.json b/package-lock.json
index b79119f..0a02ab7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "@space48/bigcommerce-api",
-  "version": "0.3.2",
+  "version": "0.3.3-alpha3",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
diff --git a/package.json b/package.json
index ad9f4dd..140bd2a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@space48/bigcommerce-api",
-  "version": "0.3.2",
+  "version": "0.3.3-alpha3",
   "description": "",
   "main": "lib/index.js",
   "types": "lib/index.d.ts",
diff --git a/src/management/index.ts b/src/management/index.ts
index 8fa2eaa..d74fb38 100644
--- a/src/management/index.ts
+++ b/src/management/index.ts
@@ -8,7 +8,8 @@ export * as V3 from "./v3";
 export type Config = {
   readonly storeHash: string;
   readonly accessToken: string;
-  readonly agent?: Agent
+  readonly agent?: Agent,
+  readonly customHeaders?: Record<string, string>
 };
 
 /**
diff --git a/src/management/v2/index.ts b/src/management/v2/index.ts
index d0247fe..256f8e0 100644
--- a/src/management/v2/index.ts
+++ b/src/management/v2/index.ts
@@ -16,14 +16,15 @@ export type InferResponse<ReqLine extends RequestLine, Params extends Parameters
     Operations[ReqLine]['response']
   >;
 
-export type ResponseData<ReqLine extends RequestLine, Params = unknown> =
+export type ResponseData<ReqLine extends RequestLine, Params extends Parameters> =
   Response.Success<ResolveResponse<ReqLine, Params>> extends { readonly body: infer Data }
     ? Data
     : never;
 
 export type Config = Omit<FetchTransportOptions, 'baseUrl' | 'headers'> & {
   readonly storeHash: string
-  readonly accessToken: string
+  readonly accessToken: string,
+  readonly customHeaders?: Record<string, string>
 };
 
 export class Client<CustomEndpoints extends string = never> {
@@ -38,7 +39,7 @@ export class Client<CustomEndpoints extends string = never> {
         : fetchTransport({
           agent: configOrTransport.agent,
           baseUrl: `https://api.bigcommerce.com/stores/${configOrTransport.storeHash}/v2`,
-          headers: { "X-Auth-Token": configOrTransport.accessToken },
+          headers: { "X-Auth-Token": configOrTransport.accessToken, ...(configOrTransport.customHeaders || {}) },
         });
   }
 
diff --git a/src/management/v3/index.ts b/src/management/v3/index.ts
index 825f328..243014d 100644
--- a/src/management/v3/index.ts
+++ b/src/management/v3/index.ts
@@ -25,6 +25,7 @@ export type ResponseData<ReqLine extends RequestLine, Params = unknown> =
 export type Config = Omit<FetchTransportOptions, 'baseUrl' | 'headers'> & {
   readonly storeHash: string
   readonly accessToken: string
+  readonly customHeaders?: Record<string, string>
 };
 
 export class Client<CustomEndpoints extends string = never> {
@@ -37,7 +38,7 @@ export class Client<CustomEndpoints extends string = never> {
       typeof configOrTransport === 'function'
         ? configOrTransport
         : fetchTransport({
-          headers: { "X-Auth-Token": configOrTransport.accessToken },
+          headers: { "X-Auth-Token": configOrTransport.accessToken, ...(configOrTransport.customHeaders || {}) },
           baseUrl: `https://api.bigcommerce.com/stores/${configOrTransport.storeHash}/v3`,
           agent: configOrTransport.agent,
         });