diff --git a/src/apiweb.zig b/src/apiweb.zig
index decac389..cbf2ffa0 100644
--- a/src/apiweb.zig
+++ b/src/apiweb.zig
@@ -39,3 +39,5 @@ pub const Interfaces = generate.Tuple(.{
     Storage.Interfaces,
     URL.Interfaces,
 });
+
+pub const UserContext = @import("user_context.zig").UserContext;
diff --git a/src/browser/browser.zig b/src/browser/browser.zig
index 2fb759cc..19982663 100644
--- a/src/browser/browser.zig
+++ b/src/browser/browser.zig
@@ -39,6 +39,9 @@ const storage = @import("../storage/storage.zig");
 
 const FetchResult = std.http.Client.FetchResult;
 
+const UserContext = @import("../user_context.zig").UserContext;
+const HttpClient = @import("../async/Client.zig");
+
 const log = std.log.scoped(.browser);
 
 // Browser is an instance of the browser.
@@ -92,6 +95,7 @@ pub const Session = struct {
     // TODO move the shed to the browser?
     storageShed: storage.Shed,
     page: ?*Page = null,
+    httpClient: HttpClient,
 
     jstypes: [Types.len]usize = undefined,
 
@@ -105,9 +109,11 @@ pub const Session = struct {
             .loader = Loader.init(alloc),
             .loop = try Loop.init(alloc),
             .storageShed = storage.Shed.init(alloc),
+            .httpClient = undefined,
         };
 
-        self.env = try Env.init(self.arena.allocator(), &self.loop);
+        self.env = try Env.init(self.arena.allocator(), &self.loop, null);
+        self.httpClient = .{ .allocator = alloc, .loop = &self.loop };
         try self.env.load(&self.jstypes);
 
         return self;
@@ -122,6 +128,7 @@ pub const Session = struct {
         self.loader.deinit();
         self.loop.deinit();
         self.storageShed.deinit();
+        self.httpClient.deinit();
         self.alloc.destroy(self);
     }
 
@@ -289,6 +296,12 @@ pub const Page = struct {
         log.debug("start js env", .{});
         try self.session.env.start(alloc);
 
+        // replace the user context document with the new one.
+        try self.session.env.setUserContext(.{
+            .document = html_doc,
+            .httpClient = &self.session.httpClient,
+        });
+
         // add global objects
         log.debug("setup global env", .{});
         try self.session.env.bindGlobal(&self.session.window);
diff --git a/src/dom/comment.zig b/src/dom/comment.zig
index c9baad26..e82c51bc 100644
--- a/src/dom/comment.zig
+++ b/src/dom/comment.zig
@@ -15,13 +15,45 @@
 //
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
+const std = @import("std");
 
 const parser = @import("../netsurf.zig");
 
+const jsruntime = @import("jsruntime");
+const Case = jsruntime.test_utils.Case;
+const checkCases = jsruntime.test_utils.checkCases;
+
 const CharacterData = @import("character_data.zig").CharacterData;
 
+const UserContext = @import("../user_context.zig").UserContext;
+
+// https://dom.spec.whatwg.org/#interface-comment
 pub const Comment = struct {
     pub const Self = parser.Comment;
     pub const prototype = *CharacterData;
     pub const mem_guarantied = true;
+
+    pub fn constructor(userctx: UserContext, data: ?[]const u8) !*parser.Comment {
+        return parser.documentCreateComment(
+            parser.documentHTMLToDocument(userctx.document),
+            data orelse "",
+        );
+    }
 };
+
+// Tests
+// -----
+
+pub fn testExecFn(
+    _: std.mem.Allocator,
+    js_env: *jsruntime.Env,
+) anyerror!void {
+    var constructor = [_]Case{
+        .{ .src = "let comment = new Comment('foo')", .ex = "undefined" },
+        .{ .src = "comment.data", .ex = "foo" },
+
+        .{ .src = "let emptycomment = new Comment()", .ex = "undefined" },
+        .{ .src = "emptycomment.data", .ex = "" },
+    };
+    try checkCases(js_env, &constructor);
+}
diff --git a/src/dom/document.zig b/src/dom/document.zig
index e9f22e76..0741b1d9 100644
--- a/src/dom/document.zig
+++ b/src/dom/document.zig
@@ -40,14 +40,26 @@ const DocumentType = @import("document_type.zig").DocumentType;
 const DocumentFragment = @import("document_fragment.zig").DocumentFragment;
 const DOMImplementation = @import("implementation.zig").DOMImplementation;
 
+const UserContext = @import("../user_context.zig").UserContext;
+
 // WEB IDL https://dom.spec.whatwg.org/#document
 pub const Document = struct {
     pub const Self = parser.Document;
     pub const prototype = *Node;
     pub const mem_guarantied = true;
 
-    pub fn constructor() !*parser.Document {
-        return try parser.domImplementationCreateHTMLDocument(null);
+    pub fn constructor(userctx: UserContext) !*parser.DocumentHTML {
+        const doc = try parser.documentCreateDocument(
+            try parser.documentHTMLGetTitle(userctx.document),
+        );
+
+        // we have to work w/ document instead of html document.
+        const ddoc = parser.documentHTMLToDocument(doc);
+        const ccur = parser.documentHTMLToDocument(userctx.document);
+        try parser.documentSetDocumentURI(ddoc, try parser.documentGetDocumentURI(ccur));
+        try parser.documentSetInputEncoding(ddoc, try parser.documentGetInputEncoding(ccur));
+
+        return doc;
     }
 
     // JS funcs
@@ -262,6 +274,13 @@ pub fn testExecFn(
         .{ .src = "newdoc.children.length", .ex = "0" },
         .{ .src = "newdoc.getElementsByTagName('*').length", .ex = "0" },
         .{ .src = "newdoc.getElementsByTagName('*').item(0)", .ex = "null" },
+        .{ .src = "newdoc.inputEncoding === document.inputEncoding", .ex = "true" },
+        .{ .src = "newdoc.documentURI === document.documentURI", .ex = "true" },
+        .{ .src = "newdoc.URL === document.URL", .ex = "true" },
+        .{ .src = "newdoc.compatMode === document.compatMode", .ex = "true" },
+        .{ .src = "newdoc.characterSet === document.characterSet", .ex = "true" },
+        .{ .src = "newdoc.charset === document.charset", .ex = "true" },
+        .{ .src = "newdoc.contentType === document.contentType", .ex = "true" },
     };
     try checkCases(js_env, &constructor);
 
diff --git a/src/dom/document_fragment.zig b/src/dom/document_fragment.zig
index 7cd1d27b..08d99165 100644
--- a/src/dom/document_fragment.zig
+++ b/src/dom/document_fragment.zig
@@ -20,20 +20,37 @@ const std = @import("std");
 
 const parser = @import("../netsurf.zig");
 
+const jsruntime = @import("jsruntime");
+const Case = jsruntime.test_utils.Case;
+const checkCases = jsruntime.test_utils.checkCases;
+
 const Node = @import("node.zig").Node;
 
+const UserContext = @import("../user_context.zig").UserContext;
+
 // WEB IDL https://dom.spec.whatwg.org/#documentfragment
 pub const DocumentFragment = struct {
     pub const Self = parser.DocumentFragment;
     pub const prototype = *Node;
     pub const mem_guarantied = true;
 
-    // TODO add constructor, but I need to associate the new DocumentFragment
-    // with the current document global object...
-    // > The new DocumentFragment() constructor steps are to set this’s node
-    // > document to current global object’s associated Document.
-    // https://dom.spec.whatwg.org/#dom-documentfragment-documentfragment
-    pub fn constructor() !*parser.DocumentFragment {
-        return error.NotImplemented;
+    pub fn constructor(userctx: UserContext) !*parser.DocumentFragment {
+        return parser.documentCreateDocumentFragment(
+            parser.documentHTMLToDocument(userctx.document),
+        );
     }
 };
+
+// Tests
+// -----
+
+pub fn testExecFn(
+    _: std.mem.Allocator,
+    js_env: *jsruntime.Env,
+) anyerror!void {
+    var constructor = [_]Case{
+        .{ .src = "const dc = new DocumentFragment()", .ex = "undefined" },
+        .{ .src = "dc.constructor.name", .ex = "DocumentFragment" },
+    };
+    try checkCases(js_env, &constructor);
+}
diff --git a/src/dom/implementation.zig b/src/dom/implementation.zig
index f7a613a0..e4fff404 100644
--- a/src/dom/implementation.zig
+++ b/src/dom/implementation.zig
@@ -75,7 +75,7 @@ pub const DOMImplementation = struct {
         return try parser.domImplementationCreateDocument(cnamespace, cqname, doctype);
     }
 
-    pub fn _createHTMLDocument(_: *DOMImplementation, title: ?[]const u8) !*parser.Document {
+    pub fn _createHTMLDocument(_: *DOMImplementation, title: ?[]const u8) !*parser.DocumentHTML {
         return try parser.domImplementationCreateHTMLDocument(title);
     }
 
@@ -95,7 +95,8 @@ pub fn testExecFn(
 ) anyerror!void {
     var getImplementation = [_]Case{
         .{ .src = "let impl = document.implementation", .ex = "undefined" },
-        .{ .src = "impl.createHTMLDocument();", .ex = "[object Document]" },
+        .{ .src = "impl.createHTMLDocument();", .ex = "[object HTMLDocument]" },
+        .{ .src = "impl.createHTMLDocument('foo');", .ex = "[object HTMLDocument]" },
         .{ .src = "impl.createDocument(null, 'foo');", .ex = "[object Document]" },
         .{ .src = "impl.createDocumentType('foo', 'bar', 'baz')", .ex = "[object DocumentType]" },
         .{ .src = "impl.hasFeature()", .ex = "true" },
diff --git a/src/dom/node.zig b/src/dom/node.zig
index 58dce2f7..5dd0c811 100644
--- a/src/dom/node.zig
+++ b/src/dom/node.zig
@@ -277,14 +277,30 @@ pub const Node = struct {
         return try Node.toInterface(res);
     }
 
+    // Check if the hierarchy node tree constraints are respected.
+    // For now, it checks only if new nodes are not self.
+    // TODO implements the others contraints.
+    // see https://dom.spec.whatwg.org/#concept-node-tree
+    pub fn hierarchy(self: *parser.Node, nodes: ?Variadic(*parser.Node)) !bool {
+        if (nodes == null) return true;
+        if (nodes.?.slice.len == 0) return true;
+
+        for (nodes.?.slice) |node| if (self == node) return false;
+
+        return true;
+    }
+
     // TODO according with https://dom.spec.whatwg.org/#parentnode, the
     // function must accept either node or string.
     // blocked by https://github.com/lightpanda-io/jsruntime-lib/issues/114
     pub fn prepend(self: *parser.Node, nodes: ?Variadic(*parser.Node)) !void {
         if (nodes == null) return;
         if (nodes.?.slice.len == 0) return;
-        const first = try parser.nodeFirstChild(self);
 
+        // check hierarchy
+        if (!try hierarchy(self, nodes)) return parser.DOMError.HierarchyRequest;
+
+        const first = try parser.nodeFirstChild(self);
         if (first == null) {
             for (nodes.?.slice) |node| {
                 _ = try parser.nodeAppendChild(self, node);
@@ -303,6 +319,10 @@ pub const Node = struct {
     pub fn append(self: *parser.Node, nodes: ?Variadic(*parser.Node)) !void {
         if (nodes == null) return;
         if (nodes.?.slice.len == 0) return;
+
+        // check hierarchy
+        if (!try hierarchy(self, nodes)) return parser.DOMError.HierarchyRequest;
+
         for (nodes.?.slice) |node| {
             _ = try parser.nodeAppendChild(self, node);
         }
@@ -312,12 +332,15 @@ pub const Node = struct {
     // function must accept either node or string.
     // blocked by https://github.com/lightpanda-io/jsruntime-lib/issues/114
     pub fn replaceChildren(self: *parser.Node, nodes: ?Variadic(*parser.Node)) !void {
-        // remove existing children
-        try removeChildren(self);
-
         if (nodes == null) return;
         if (nodes.?.slice.len == 0) return;
 
+        // check hierarchy
+        if (!try hierarchy(self, nodes)) return parser.DOMError.HierarchyRequest;
+
+        // remove existing children
+        try removeChildren(self);
+
         // add new children
         for (nodes.?.slice) |node| {
             _ = try parser.nodeAppendChild(self, node);
diff --git a/src/dom/text.zig b/src/dom/text.zig
index a64c4d88..4ac35ed5 100644
--- a/src/dom/text.zig
+++ b/src/dom/text.zig
@@ -28,6 +28,8 @@ const parser = @import("../netsurf.zig");
 const CharacterData = @import("character_data.zig").CharacterData;
 const CDATASection = @import("cdata_section.zig").CDATASection;
 
+const UserContext = @import("../user_context.zig").UserContext;
+
 // Text interfaces
 pub const Interfaces = generate.Tuple(.{
     CDATASection,
@@ -38,6 +40,13 @@ pub const Text = struct {
     pub const prototype = *CharacterData;
     pub const mem_guarantied = true;
 
+    pub fn constructor(userctx: UserContext, data: ?[]const u8) !*parser.Text {
+        return parser.documentCreateTextNode(
+            parser.documentHTMLToDocument(userctx.document),
+            data orelse "",
+        );
+    }
+
     // JS funcs
     // --------
 
@@ -62,6 +71,15 @@ pub fn testExecFn(
     _: std.mem.Allocator,
     js_env: *jsruntime.Env,
 ) anyerror!void {
+    var constructor = [_]Case{
+        .{ .src = "let t = new Text('foo')", .ex = "undefined" },
+        .{ .src = "t.data", .ex = "foo" },
+
+        .{ .src = "let emptyt = new Text()", .ex = "undefined" },
+        .{ .src = "emptyt.data", .ex = "" },
+    };
+    try checkCases(js_env, &constructor);
+
     var get_whole_text = [_]Case{
         .{ .src = "let text = document.getElementById('link').firstChild", .ex = "undefined" },
         .{ .src = "text.wholeText === 'OK'", .ex = "true" },
diff --git a/src/main.zig b/src/main.zig
index 1c032b68..ab4fb585 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -25,6 +25,7 @@ const apiweb = @import("apiweb.zig");
 const Window = @import("html/window.zig").Window;
 
 pub const Types = jsruntime.reflect(apiweb.Interfaces);
+pub const UserContext = apiweb.UserContext;
 
 const socket_path = "/tmp/browsercore-server.sock";
 
@@ -103,5 +104,5 @@ pub fn main() !void {
     try server.listen(addr);
     std.debug.print("Listening on: {s}...\n", .{socket_path});
 
-    try jsruntime.loadEnv(&arena, execJS);
+    try jsruntime.loadEnv(&arena, null, execJS);
 }
diff --git a/src/main_get.zig b/src/main_get.zig
index 579edca2..387106a6 100644
--- a/src/main_get.zig
+++ b/src/main_get.zig
@@ -23,6 +23,7 @@ const jsruntime = @import("jsruntime");
 const apiweb = @import("apiweb.zig");
 
 pub const Types = jsruntime.reflect(apiweb.Interfaces);
+pub const UserContext = apiweb.UserContext;
 
 pub const std_options = struct {
     pub const log_level = .debug;
diff --git a/src/main_shell.zig b/src/main_shell.zig
index 4b4967d1..6eb6c11a 100644
--- a/src/main_shell.zig
+++ b/src/main_shell.zig
@@ -28,6 +28,8 @@ const storage = @import("storage/storage.zig");
 const html_test = @import("html_test.zig").html;
 
 pub const Types = jsruntime.reflect(apiweb.Interfaces);
+pub const UserContext = apiweb.UserContext;
+const Client = @import("async/Client.zig");
 
 var doc: *parser.DocumentHTML = undefined;
 
@@ -39,6 +41,14 @@ fn execJS(
     try js_env.start(alloc);
     defer js_env.stop();
 
+    var cli = Client{ .allocator = alloc, .loop = js_env.nat_ctx.loop };
+    defer cli.deinit();
+
+    try js_env.setUserContext(UserContext{
+        .document = doc,
+        .httpClient = &cli,
+    });
+
     var storageShelf = storage.Shelf.init(alloc);
     defer storageShelf.deinit();
 
diff --git a/src/main_wpt.zig b/src/main_wpt.zig
index 06c6a249..bc9927fd 100644
--- a/src/main_wpt.zig
+++ b/src/main_wpt.zig
@@ -49,6 +49,7 @@ const Out = enum {
 
 pub const Types = jsruntime.reflect(apiweb.Interfaces);
 pub const GlobalType = apiweb.GlobalType;
+pub const UserContext = apiweb.UserContext;
 
 // TODO For now the WPT tests run is specific to WPT.
 // It manually load js framwork libs, and run the first script w/ js content in
diff --git a/src/netsurf.zig b/src/netsurf.zig
index f5b3a141..0c4f3b8a 100644
--- a/src/netsurf.zig
+++ b/src/netsurf.zig
@@ -1763,21 +1763,29 @@ pub inline fn domImplementationCreateDocumentType(
     return dt.?;
 }
 
-pub inline fn domImplementationCreateHTMLDocument(title: ?[]const u8) !*Document {
-    var doc: ?*Document = undefined;
-    const err = c.dom_implementation_create_document(
-        c.DOM_IMPLEMENTATION_HTML,
-        null,
-        null,
-        null,
-        null,
-        null,
-        &doc,
-    );
-    try DOMErr(err);
-    // TODO set title
-    _ = title;
-    return doc.?;
+pub inline fn domImplementationCreateHTMLDocument(title: ?[]const u8) !*DocumentHTML {
+    const doc_html = try documentCreateDocument(title);
+    const doc = documentHTMLToDocument(doc_html);
+
+    // add hierarchy: html, head, body.
+    const html = try documentCreateElement(doc, "html");
+    _ = try nodeAppendChild(documentToNode(doc), elementToNode(html));
+
+    const head = try documentCreateElement(doc, "head");
+    _ = try nodeAppendChild(elementToNode(html), elementToNode(head));
+
+    if (title) |t| {
+        try documentHTMLSetTitle(doc_html, t);
+        const htitle = try documentCreateElement(doc, "title");
+        const txt = try documentCreateTextNode(doc, t);
+        _ = try nodeAppendChild(elementToNode(htitle), @as(*Node, @ptrCast(txt)));
+        _ = try nodeAppendChild(elementToNode(head), elementToNode(htitle));
+    }
+
+    const body = try documentCreateElement(doc, "body");
+    _ = try nodeAppendChild(elementToNode(html), elementToNode(body));
+
+    return doc_html;
 }
 
 // Document
@@ -1833,6 +1841,28 @@ pub inline fn documentGetInputEncoding(doc: *Document) ![]const u8 {
     return strToData(s.?);
 }
 
+pub inline fn documentSetInputEncoding(doc: *Document, enc: []const u8) !void {
+    const err = documentVtable(doc).dom_document_set_input_encoding.?(doc, try strFromData(enc));
+    try DOMErr(err);
+}
+
+pub inline fn documentCreateDocument(title: ?[]const u8) !*DocumentHTML {
+    var doc: ?*Document = undefined;
+    const err = c.dom_implementation_create_document(
+        c.DOM_IMPLEMENTATION_HTML,
+        null,
+        null,
+        null,
+        null,
+        null,
+        &doc,
+    );
+    try DOMErr(err);
+    const doc_html = @as(*DocumentHTML, @ptrCast(doc.?));
+    if (title) |t| try documentHTMLSetTitle(doc_html, t);
+    return doc_html;
+}
+
 pub inline fn documentCreateElement(doc: *Document, tag_name: []const u8) !*Element {
     var elem: ?*Element = undefined;
     const err = documentVtable(doc).dom_document_create_element.?(doc, try strFromData(tag_name), &elem);
diff --git a/src/run_tests.zig b/src/run_tests.zig
index 3fe20b3f..700d15c0 100644
--- a/src/run_tests.zig
+++ b/src/run_tests.zig
@@ -30,6 +30,7 @@ const xhr = @import("xhr/xhr.zig");
 const storage = @import("storage/storage.zig");
 const url = @import("url/url.zig");
 const urlquery = @import("url/query.zig");
+const Client = @import("async/Client.zig");
 
 const documentTestExecFn = @import("dom/document.zig").testExecFn;
 const HTMLDocumentTestExecFn = @import("html/document.zig").testExecFn;
@@ -46,6 +47,8 @@ const NodeListTestExecFn = @import("dom/nodelist.zig").testExecFn;
 const AttrTestExecFn = @import("dom/attribute.zig").testExecFn;
 const EventTargetTestExecFn = @import("dom/event_target.zig").testExecFn;
 const ProcessingInstructionTestExecFn = @import("dom/processing_instruction.zig").testExecFn;
+const CommentTestExecFn = @import("dom/comment.zig").testExecFn;
+const DocumentFragmentTestExecFn = @import("dom/document_fragment.zig").testExecFn;
 const EventTestExecFn = @import("events/event.zig").testExecFn;
 const XHRTestExecFn = xhr.testExecFn;
 const ProgressEventTestExecFn = @import("xhr/progress_event.zig").testExecFn;
@@ -54,6 +57,7 @@ const URLTestExecFn = url.testExecFn;
 const HTMLElementTestExecFn = @import("html/elements.zig").testExecFn;
 
 pub const Types = jsruntime.reflect(apiweb.Interfaces);
+pub const UserContext = @import("user_context.zig").UserContext;
 
 var doc: *parser.DocumentHTML = undefined;
 
@@ -81,6 +85,14 @@ fn testExecFn(
         std.debug.print("documentHTMLClose error: {s}\n", .{@errorName(err)});
     };
 
+    var cli = Client{ .allocator = alloc, .loop = js_env.nat_ctx.loop };
+    defer cli.deinit();
+
+    try js_env.setUserContext(.{
+        .document = doc,
+        .httpClient = &cli,
+    });
+
     // alias global as self and window
     var window = Window.create(null);
 
@@ -111,6 +123,8 @@ fn testsAllExecFn(
         DOMTokenListExecFn,
         NodeListTestExecFn,
         AttrTestExecFn,
+        CommentTestExecFn,
+        DocumentFragmentTestExecFn,
         EventTargetTestExecFn,
         EventTestExecFn,
         XHRTestExecFn,
@@ -315,7 +329,7 @@ fn testJSRuntime(alloc: std.mem.Allocator) !void {
     var arena_alloc = std.heap.ArenaAllocator.init(alloc);
     defer arena_alloc.deinit();
 
-    try jsruntime.loadEnv(&arena_alloc, testsAllExecFn);
+    try jsruntime.loadEnv(&arena_alloc, null, testsAllExecFn);
 }
 
 test "DocumentHTMLParseFromStr" {
diff --git a/src/test_runner.zig b/src/test_runner.zig
index d385c813..8b138d0b 100644
--- a/src/test_runner.zig
+++ b/src/test_runner.zig
@@ -21,6 +21,7 @@ const std = @import("std");
 const tests = @import("run_tests.zig");
 
 pub const Types = tests.Types;
+pub const UserContext = tests.UserContext;
 
 pub fn main() !void {
     try tests.main();
diff --git a/src/user_context.zig b/src/user_context.zig
new file mode 100644
index 00000000..4860100d
--- /dev/null
+++ b/src/user_context.zig
@@ -0,0 +1,8 @@
+const std = @import("std");
+const parser = @import("netsurf.zig");
+const Client = @import("async/Client.zig");
+
+pub const UserContext = struct {
+    document: *parser.DocumentHTML,
+    httpClient: *Client,
+};
diff --git a/src/wpt/run.zig b/src/wpt/run.zig
index c7c263a5..4322ee40 100644
--- a/src/wpt/run.zig
+++ b/src/wpt/run.zig
@@ -30,6 +30,8 @@ const Window = @import("../html/window.zig").Window;
 const storage = @import("../storage/storage.zig");
 
 const Types = @import("../main_wpt.zig").Types;
+const UserContext = @import("../main_wpt.zig").UserContext;
+const Client = @import("../async/Client.zig");
 
 // runWPT parses the given HTML file, starts a js env and run the first script
 // tags containing javascript sources.
@@ -50,7 +52,14 @@ pub fn run(arena: *std.heap.ArenaAllocator, comptime dir: []const u8, f: []const
     // create JS env
     var loop = try Loop.init(alloc);
     defer loop.deinit();
-    var js_env = try Env.init(alloc, &loop);
+
+    var cli = Client{ .allocator = alloc, .loop = &loop };
+    defer cli.deinit();
+
+    var js_env = try Env.init(alloc, &loop, UserContext{
+        .document = html_doc,
+        .httpClient = &cli,
+    });
     defer js_env.deinit();
 
     var storageShelf = storage.Shelf.init(alloc);
diff --git a/src/xhr/xhr.zig b/src/xhr/xhr.zig
index 8719e2fc..e395144a 100644
--- a/src/xhr/xhr.zig
+++ b/src/xhr/xhr.zig
@@ -37,6 +37,8 @@ const Client = @import("../async/Client.zig");
 
 const parser = @import("../netsurf.zig");
 
+const UserContext = @import("../user_context.zig").UserContext;
+
 const log = std.log.scoped(.xhr);
 
 // XHR interfaces
@@ -149,7 +151,7 @@ pub const XMLHttpRequest = struct {
 
     proto: XMLHttpRequestEventTarget = XMLHttpRequestEventTarget{},
     alloc: std.mem.Allocator,
-    cli: Client,
+    cli: *Client,
     impl: YieldImpl,
 
     priv_state: PrivState = .new,
@@ -185,7 +187,7 @@ pub const XMLHttpRequest = struct {
 
     const min_delay: u64 = 50000000; // 50ms
 
-    pub fn constructor(alloc: std.mem.Allocator, loop: *Loop) !XMLHttpRequest {
+    pub fn constructor(alloc: std.mem.Allocator, loop: *Loop, userctx: UserContext) !XMLHttpRequest {
         return .{
             .alloc = alloc,
             .headers = .{ .allocator = alloc, .owned = true },
@@ -195,8 +197,7 @@ pub const XMLHttpRequest = struct {
             .url = null,
             .uri = undefined,
             .state = UNSENT,
-            // TODO retrieve the HTTP client globally to reuse existing connections.
-            .cli = .{ .allocator = alloc, .loop = loop },
+            .cli = userctx.httpClient,
         };
     }
 
@@ -235,9 +236,6 @@ pub const XMLHttpRequest = struct {
         self.response_headers.deinit();
 
         self.proto.deinit(alloc);
-
-        // TODO the client must be shared between requests.
-        self.cli.deinit();
     }
 
     pub fn get_readyState(self: *XMLHttpRequest) u16 {
diff --git a/vendor/zig-js-runtime b/vendor/zig-js-runtime
index fff1a677..d4a2eaef 160000
--- a/vendor/zig-js-runtime
+++ b/vendor/zig-js-runtime
@@ -1 +1 @@
-Subproject commit fff1a6778dfc91d71d77e5c593283b2aba78432f
+Subproject commit d4a2eaefd8390b9483e5ad58d2992dc381632559