diff --git a/urequest.js b/urequest.js
index ec48572..99f18fc 100644
--- a/urequest.js
+++ b/urequest.js
@@ -1,223 +1,229 @@
-'use strict';
+(function (exports) {
+    'use strict';
 
-/**
- * @typedef {import('./').Request} Request
- * @typedef {import('./').RequestOptions} RequestOptions
- * @typedef {import('./').Response} Response
- * @typedef {import('./').Headers} Headers
- */
-
-// `fetch` will be available for node and browsers as a global
-//var fetch = window.fetch;
-
-// https://developer.mozilla.org/en-US/docs/Web/API/fetch
-// https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch
-let _fetchDefaults = {
-    method: 'GET', // *GET, POST, PATCH, PUT, DELETE, etc
-    headers: {},
-    body: undefined, // String, ArrayBuffer, FormData, etc
-    mode: 'cors', // no-cors, *cors, same-origin
-    credentials: 'same-origin', // omit, *same-origin, include
-    cache: 'default', // *default, no-store, reload, no-cache, force-cache, only-if-cached
-    redirect: 'follow', // *follow, error, manual,
-    referrer: undefined,
-    referrerPolicy: 'no-referrer-when-downgrade', // no-referrer, *no-referrer-when-downgrade, same-origin, origin, strict-origin, origin-when-cross-origin, strict-origin-when-cross-origin, unsafe-url
-    integrity: '',
-    keepalive: false,
-    signal: null //
-};
-
-let _optionKeys = Object.keys(_fetchDefaults).concat([
-    //'encoding', // N/A
-    //'stream', // TODO via getReader
-    //'json' // handled manually
-    //'form', // TODO
-    //'auth' // handled manually
-    //'formData', // TODO
-    //'FormData', // TODO
-    //'userAgent' // not allowed, non-standard for request.js
-]);
-
-/**
- * @returns {Request>}
- */
-function setDefaults(_defs) {
     /**
-     * @param {RequestOptions} opts
-     * @returns {Promise<Response>}
-     **/
-    async function request(opts) {
-        if ('string' === typeof opts) {
-            opts = { url: opts };
-        }
-        let reqOpts = { headers: {} };
+     * @typedef {import('./').Request} Request
+     * @typedef {import('./').RequestOptions} RequestOptions
+     * @typedef {import('./').Response} Response
+     * @typedef {import('./').Headers} Headers
+     */
 
-        if (
-            opts.body ||
-            (opts.json && true !== opts.json) ||
-            opts.form ||
-            opts.formData
-        ) {
-            // TODO this is probably a deviation from request's API
-            // need to check and probably eliminate it
-            reqOpts.method = (reqOpts.method || 'POST').toUpperCase();
-        } else {
-            reqOpts.method = (reqOpts.method || 'GET').toUpperCase();
-        }
+    // `fetch` will be available for node and browsers as a global
+    //var fetch = window.fetch;
 
-        _optionKeys.forEach(function (key) {
-            if (key in opts) {
-                if ('undefined' !== typeof opts[key]) {
-                    reqOpts[key] = opts[key];
+    // https://developer.mozilla.org/en-US/docs/Web/API/fetch
+    // https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch
+    let _fetchDefaults = {
+        method: 'GET', // *GET, POST, PATCH, PUT, DELETE, etc
+        headers: {},
+        body: undefined, // String, ArrayBuffer, FormData, etc
+        mode: 'cors', // no-cors, *cors, same-origin
+        credentials: 'same-origin', // omit, *same-origin, include
+        cache: 'default', // *default, no-store, reload, no-cache, force-cache, only-if-cached
+        redirect: 'follow', // *follow, error, manual,
+        referrer: undefined,
+        referrerPolicy: 'no-referrer-when-downgrade', // no-referrer, *no-referrer-when-downgrade, same-origin, origin, strict-origin, origin-when-cross-origin, strict-origin-when-cross-origin, unsafe-url
+        integrity: '',
+        keepalive: false,
+        signal: null //
+    };
+
+    let _optionKeys = Object.keys(_fetchDefaults).concat([
+        //'encoding', // N/A
+        //'stream', // TODO via getReader
+        //'json' // handled manually
+        //'form', // TODO
+        //'auth' // handled manually
+        //'formData', // TODO
+        //'FormData', // TODO
+        //'userAgent' // not allowed, non-standard for request.js
+    ]);
+
+    /**
+     * @returns {Request>}
+     */
+    function setDefaults(_defs) {
+        /**
+         * @param {RequestOptions} opts
+         * @returns {Promise<Response>}
+         **/
+        async function request(opts) {
+            if ('string' === typeof opts) {
+                opts = { url: opts };
+            }
+            let reqOpts = { headers: {} };
+
+            if (
+                opts.body ||
+                (opts.json && true !== opts.json) ||
+                opts.form ||
+                opts.formData
+            ) {
+                // TODO this is probably a deviation from request's API
+                // need to check and probably eliminate it
+                reqOpts.method = (reqOpts.method || 'POST').toUpperCase();
+            } else {
+                reqOpts.method = (reqOpts.method || 'GET').toUpperCase();
+            }
+
+            _optionKeys.forEach(function (key) {
+                if (key in opts) {
+                    if ('undefined' !== typeof opts[key]) {
+                        reqOpts[key] = opts[key];
+                    }
+                } else if (key in _defs) {
+                    reqOpts[key] = _defs[key];
                 }
-            } else if (key in _defs) {
-                reqOpts[key] = _defs[key];
-            }
-        });
+            });
 
-        if (opts.auth) {
-            // if opts.uri specifies auth it will be parsed by url.parse and passed directly to the http module
-            if ('string' !== typeof opts.auth) {
-                let u = opts.auth.user || opts.auth.username || '';
-                let p = opts.auth.pass || opts.auth.password || '';
-                reqOpts.headers.Authorization = encodeBasicAuth(`${u}:${p}`);
-            } else if ('string' === typeof opts.auth) {
-                reqOpts.headers.Authorization = encodeBasicAuth(`${opts.auth}`);
+            if (opts.auth) {
+                // if opts.uri specifies auth it will be parsed by url.parse and passed directly to the http module
+                if ('string' !== typeof opts.auth) {
+                    let u = opts.auth.user || opts.auth.username || '';
+                    let p = opts.auth.pass || opts.auth.password || '';
+                    reqOpts.headers.Authorization = encodeBasicAuth(
+                        `${u}:${p}`
+                    );
+                } else if ('string' === typeof opts.auth) {
+                    reqOpts.headers.Authorization = encodeBasicAuth(
+                        `${opts.auth}`
+                    );
+                }
+
+                // [request-compat]
+                if (opts.auth.bearer) {
+                    // having a shortcut for base64 encoding makes sense,
+                    // but this? Eh, whatevs...
+                    reqOpts.header.Authorization = `Bearer ${opts.auth.bearer}`;
+                }
             }
 
-            // [request-compat]
-            if (opts.auth.bearer) {
-                // having a shortcut for base64 encoding makes sense,
-                // but this? Eh, whatevs...
-                reqOpts.header.Authorization = `Bearer ${opts.auth.bearer}`;
+            let body;
+            if (opts.json && true !== opts.json) {
+                if (!opts.headers['content-type']) {
+                    opts.headers['content-type'] = 'application/json';
+                }
+                body = JSON.stringify(opts.json);
+                if (!opts.method) {
+                    opts.method = 'POST';
+                }
             }
-        }
 
-        let body;
-        if (opts.json && true !== opts.json) {
-            if (!opts.headers['content-type']) {
-                opts.headers['content-type'] = 'application/json';
+            // The node version will send HTTP Auth by default, but not Cookies.
+            // We don't have an equivalent option for `fetch`. Furthermore,
+            // `fetch` caches HTTP Auth Basic across browser refreshes,
+            // which is not analogous to the node behavior.
+            //
+            // "In the face of ambiguity, refuse the temptation to guess"
+            //
+            //if (!('credentials' in opts)) {
+            //    opts.credentials = 'include';
+            //}
+
+            if (!('mode' in opts)) {
+                reqOpts.mode = 'cors';
             }
-            body = JSON.stringify(opts.json);
-            if (!opts.method) {
-                opts.method = 'POST';
+            if (!('body' in opts)) {
+                if (body) {
+                    reqOpts.body = body;
+                }
             }
-        }
 
-        // The node version will send HTTP Auth by default, but not Cookies.
-        // We don't have an equivalent option for `fetch`. Furthermore,
-        // `fetch` caches HTTP Auth Basic across browser refreshes,
-        // which is not analogous to the node behavior.
-        //
-        // "In the face of ambiguity, refuse the temptation to guess"
-        //
-        //if (!('credentials' in opts)) {
-        //    opts.credentials = 'include';
-        //}
+            let resp = await fetch(opts.url, reqOpts);
 
-        if (!('mode' in opts)) {
-            reqOpts.mode = 'cors';
-        }
-        if (!('body' in opts)) {
-            if (body) {
-                reqOpts.body = body;
-            }
-        }
-
-        let resp = await fetch(opts.url, reqOpts);
-
-        let result = {
-            ok: resp.ok,
-            headers: headersToObj(resp.headers),
-            body: undefined,
-            // swapped to match request.js
-            statusCode: resp.status,
-            status: resp.statusText,
-            request: reqOpts,
-            response: resp
-        };
-        result.toJSON = function () {
-            return {
-                ok: result.ok,
-                headers: result.headers,
-                body: result.body,
-                statusCode: result.statusCode,
-                status: result.status
+            let result = {
+                ok: resp.ok,
+                headers: headersToObj(resp.headers),
+                body: undefined,
+                // swapped to match request.js
+                statusCode: resp.status,
+                status: resp.statusText,
+                request: reqOpts,
+                response: resp
+            };
+            result.toJSON = function () {
+                return {
+                    ok: result.ok,
+                    headers: result.headers,
+                    body: result.body,
+                    statusCode: result.statusCode,
+                    status: result.status
+                };
             };
-        };
 
-        // return early if there's no body
-        if (!result.headers['content-type']) {
+            // return early if there's no body
+            if (!result.headers['content-type']) {
+                return result;
+            }
+
+            // TODO blob, formData ?
+            if (null === opts.encoding) {
+                return await resp.arrayBuffer();
+            }
+
+            if (!opts.json) {
+                result.body = await resp.text();
+            } else {
+                result.body = await resp.json().catch(async function () {
+                    return await resp.text();
+                });
+            }
             return result;
         }
 
-        // TODO blob, formData ?
-        if (null === opts.encoding) {
-            return await resp.arrayBuffer();
-        }
-
-        if (!opts.json) {
-            result.body = await resp.text();
-        } else {
-            result.body = await resp.json().catch(async function () {
-                return await resp.text();
-            });
-        }
-        return result;
+        return request;
     }
 
-    return request;
-}
-
-/**
- * @param {Iterable.<*>} rheaders
- * @returns {Object.<String, String>}
- */
-function headersToObj(rheaders) {
-    /*
+    /**
+     * @param {Iterable.<*>} rheaders
+     * @returns {Object.<String, String>}
+     */
+    function headersToObj(rheaders) {
+        /*
     Array.from(resp.headers.entries()).forEach(function (h) {
         headers[h[0]] = h[1];
     });
     */
-    let headerNames = Array.from(rheaders.keys());
-    let resHeaders = {};
-    headerNames.forEach(function (k) {
-        resHeaders[k] = rheaders.get(k);
-    });
-    return resHeaders;
-}
+        let headerNames = Array.from(rheaders.keys());
+        let resHeaders = {};
+        headerNames.forEach(function (k) {
+            resHeaders[k] = rheaders.get(k);
+        });
+        return resHeaders;
+    }
 
-/**
- * @param {String} utf8
- * @returns {String}
- */
-function encodeBasicAuth(utf8) {
-    let b64 = unicodeToBase64(utf8);
-    return `Basic ${b64}`;
-}
+    /**
+     * @param {String} utf8
+     * @returns {String}
+     */
+    function encodeBasicAuth(utf8) {
+        let b64 = unicodeToBase64(utf8);
+        return `Basic ${b64}`;
+    }
 
-/**
- * @param {String} utf8
- * @returns {String}
- */
-function unicodeToBase64(utf8) {
-    let str = '';
-    let uint8 = new TextEncoder().encode(utf8);
-    uint8.forEach(function (b) {
-        str += String.fromCharCode(b);
-    });
-    let b64 = btoa(str);
-    return b64;
-}
+    /**
+     * @param {String} utf8
+     * @returns {String}
+     */
+    function unicodeToBase64(utf8) {
+        let str = '';
+        let uint8 = new TextEncoder().encode(utf8);
+        uint8.forEach(function (b) {
+            str += String.fromCharCode(b);
+        });
+        let b64 = btoa(str);
+        return b64;
+    }
 
-let defaultRequest = setDefaults({ mode: 'cors' });
-//@ts-ignore
-exports.urequest = defaultRequest;
-//@ts-ignore
-exports.urequest.defaults = setDefaults;
+    let defaultRequest = setDefaults({ mode: 'cors' });
+    //@ts-ignore
+    exports.urequest = defaultRequest;
+    //@ts-ignore
+    exports.urequest.defaults = setDefaults;
 
-// for backwards compat
-if ('undefined' !== typeof module) {
-    module.exports = defaultRequest;
-    module.exports.defaults = setDefaults;
-}
+    // for backwards compat
+    if ('undefined' !== typeof module) {
+        module.exports = defaultRequest;
+        module.exports.defaults = setDefaults;
+    }
+})(('undefined' !== typeof module && module.exports) || window);