diff --git a/demo/src/app/views/redirect.zig b/demo/src/app/views/redirect.zig
index efef2fd..7b951c4 100644
--- a/demo/src/app/views/redirect.zig
+++ b/demo/src/app/views/redirect.zig
@@ -5,7 +5,15 @@ pub fn index(request: *jetzig.Request, data: *jetzig.Data) !jetzig.View {
     _ = data;
     const params = try request.params();
     if (params.get("redirect")) |location| {
-        return request.redirect(try location.toString(), .moved_permanently);
+        switch (location.*) {
+            // Value is `.Null` when param is empty, e.g.:
+            // `http://localhost:8080/redirect?redirect`
+            .Null => return request.redirect("http://www.example.com/", .moved_permanently),
+            // Value is `.string` when param is present, e.g.:
+            // `http://localhost:8080/redirect?redirect=https://jetzig.dev/`
+            .string => |string| return request.redirect(string.value, .moved_permanently),
+            else => unreachable,
+        }
     }
 
     return request.render(.ok);
diff --git a/src/jetzig/http/Query.zig b/src/jetzig/http/Query.zig
index 5faaaff..14c76d1 100644
--- a/src/jetzig/http/Query.zig
+++ b/src/jetzig/http/Query.zig
@@ -1,7 +1,7 @@
 const std = @import("std");
 const jetzig = @import("../../jetzig.zig");
 
-const Self = @This();
+const Query = @This();
 
 allocator: std.mem.Allocator,
 query_string: []const u8,
@@ -10,10 +10,10 @@ data: *jetzig.data.Data,
 
 pub const QueryItem = struct {
     key: []const u8,
-    value: []const u8,
+    value: ?[]const u8,
 };
 
-pub fn init(allocator: std.mem.Allocator, query_string: []const u8, data: *jetzig.data.Data) Self {
+pub fn init(allocator: std.mem.Allocator, query_string: []const u8, data: *jetzig.data.Data) Query {
     return .{
         .allocator = allocator,
         .query_string = query_string,
@@ -22,19 +22,19 @@ pub fn init(allocator: std.mem.Allocator, query_string: []const u8, data: *jetzi
     };
 }
 
-pub fn deinit(self: *Self) void {
+pub fn deinit(self: *Query) void {
     self.query_items.deinit();
     self.data.deinit();
 }
 
-pub fn parse(self: *Self) !void {
+pub fn parse(self: *Query) !void {
     var pairs_it = std.mem.splitScalar(u8, self.query_string, '&');
 
     while (pairs_it.next()) |pair| {
         var key_value_it = std.mem.splitScalar(u8, pair, '=');
         var count: u2 = 0;
         var key: []const u8 = undefined;
-        var value: []const u8 = undefined;
+        var value: ?[]const u8 = null;
 
         while (key_value_it.next()) |key_or_value| {
             switch (count) {
@@ -53,27 +53,27 @@ pub fn parse(self: *Self) !void {
         if (arrayParam(item.key)) |key| {
             if (params.get(key)) |value| {
                 switch (value.*) {
-                    .array => try value.array.append(self.data.string(item.value)),
+                    .array => try value.array.append(self.dataValue(item.value)),
                     else => return error.JetzigQueryParseError,
                 }
             } else {
                 var array = try self.data.createArray();
-                try array.append(self.data.string(item.value));
+                try array.append(self.dataValue(item.value));
                 try params.put(key, array);
             }
         } else if (mappingParam(item.key)) |mapping| {
             if (params.get(mapping.key)) |value| {
                 switch (value.*) {
-                    .object => try value.object.put(mapping.field, self.data.string(item.value)),
+                    .object => try value.object.put(mapping.field, self.dataValue(item.value)),
                     else => return error.JetzigQueryParseError,
                 }
             } else {
                 var object = try self.data.createObject();
-                try object.put(mapping.field, self.data.string(item.value));
+                try object.put(mapping.field, self.dataValue(item.value));
                 try params.put(mapping.key, object);
             }
         } else {
-            try params.put(item.key, self.data.string(item.value));
+            try params.put(item.key, self.dataValue(item.value));
         }
     }
 }
@@ -103,6 +103,14 @@ fn mappingParam(input: []const u8) ?struct { key: []const u8, field: []const u8
     };
 }
 
+fn dataValue(self: Query, value: ?[]const u8) *jetzig.data.Data.Value {
+    if (value) |item_value| {
+        return self.data.string(item_value);
+    } else {
+        return self.data._null();
+    }
+}
+
 test "simple query string" {
     const allocator = std.testing.allocator;
     const query_string = "foo=bar&baz=qux";
@@ -155,3 +163,26 @@ test "query string with mapping values" {
         else => unreachable,
     }
 }
+
+test "query string with param without value" {
+    const allocator = std.testing.allocator;
+    const query_string = "foo&bar";
+    var data = jetzig.data.Data.init(allocator);
+
+    var query = init(allocator, query_string, &data);
+    defer query.deinit();
+
+    try query.parse();
+
+    const foo = try data.get("foo");
+    try switch (foo.*) {
+        .Null => {},
+        else => std.testing.expect(false),
+    };
+
+    const bar = try data.get("bar");
+    try switch (bar.*) {
+        .Null => {},
+        else => std.testing.expect(false),
+    };
+}
diff --git a/src/jetzig/http/Server.zig b/src/jetzig/http/Server.zig
index 349d3f9..1a12a2c 100644
--- a/src/jetzig/http/Server.zig
+++ b/src/jetzig/http/Server.zig
@@ -146,6 +146,7 @@ fn renderHTML(
     if (route) |matched_route| {
         const template = zmpl.find(matched_route.template);
         if (template == null) {
+            request.response_data.noop(bool, false); // FIXME: Weird Zig bug ? Any call here fixes it.
             if (try self.renderMarkdown(request, route)) |rendered_markdown| {
                 return request.setResponse(rendered_markdown, .{});
             }
@@ -376,7 +377,7 @@ fn renderNotFound(request: *jetzig.http.Request) !RenderedView {
 fn renderBadRequest(request: *jetzig.http.Request) !RenderedView {
     request.response_data.reset();
 
-    const status: jetzig.http.StatusCode = .not_found;
+    const status: jetzig.http.StatusCode = .bad_request;
     const content = try request.formatStatus(status);
     return .{
         .view = jetzig.views.View{ .data = request.response_data, .status_code = status },