diff --git a/src/jetzig/channels/Channel.zig b/src/jetzig/channels/Channel.zig
index 58ae978..8be350c 100644
--- a/src/jetzig/channels/Channel.zig
+++ b/src/jetzig/channels/Channel.zig
@@ -113,11 +113,19 @@ pub fn RoutedChannel(Routes: type) type {
                 break :blk id;
             };
 
-            const connection_key = try std.fmt.allocPrint(channel.allocator, "{s}:{s}", .{ channel.websocket.session_id, connection_id });
+            const connection_key = try std.fmt.allocPrint(
+                channel.allocator,
+                "{s}:{s}",
+                .{ channel.websocket.session_id, connection_id },
+            );
             const channel_state = try channel.websocket.channels.get(channel.data, connection_key) orelse blk: {
                 const channel_state = try channel.data.object();
                 // TODO - store this in a way that won't clobber the key with each new state.
-                try channel_state.put("__connection_url__", try std.fmt.allocPrint(channel.allocator, "http://{s}{s}?key={s}", .{ channel.host, channel.path, connection_key }));
+                try channel_state.put("__connection_url__", try std.fmt.allocPrint(
+                    channel.allocator,
+                    "http://{s}{s}?key={s}",
+                    .{ channel.host, channel.path, connection_key },
+                ));
                 try channel.websocket.channels.put(connection_key, channel_state);
                 break :blk channel_state;
             };
@@ -126,6 +134,7 @@ pub fn RoutedChannel(Routes: type) type {
         }
 
         pub fn connect(channel: Channel, comptime scope: []const u8, session_id: []const u8) !void {
+            std.debug.print("here\n", .{});
             _ = channel;
             _ = scope;
             _ = session_id;
diff --git a/src/jetzig/http/Headers.zig b/src/jetzig/http/Headers.zig
index 3d719a7..cdd70ab 100644
--- a/src/jetzig/http/Headers.zig
+++ b/src/jetzig/http/Headers.zig
@@ -7,16 +7,21 @@ const jetzig = @import("../../jetzig.zig");
 allocator: std.mem.Allocator,
 httpz_headers: *httpz.key_value.StringKeyValue,
 new_headers: std.ArrayList(Header),
+options: Options,
 
 const Headers = @This();
-const Header = struct { name: []const u8, value: []const u8 };
+pub const Header = struct { name: []const u8, value: []const u8 };
 const max_bytes_header_name = jetzig.config.get(u8, "max_bytes_header_name");
 
-pub fn init(allocator: std.mem.Allocator, httpz_headers: *httpz.key_value.StringKeyValue) Headers {
+pub const Options = struct {
+    read_only: bool = false,
+};
+pub fn init(allocator: std.mem.Allocator, httpz_headers: *httpz.key_value.StringKeyValue, options: Options) Headers {
     return .{
         .allocator = allocator,
         .httpz_headers = httpz_headers,
         .new_headers = std.ArrayList(Header).init(allocator),
+        .options = options,
     };
 }
 
@@ -41,6 +46,20 @@ pub fn get(self: Headers, name: []const u8) ?[]const u8 {
     return self.httpz_headers.get(lower);
 }
 
+/// Determine if a header exists. Names are case-insensitive.
+pub fn has(self: Headers, name: []const u8) bool {
+    std.debug.assert(name.len <= max_bytes_header_name);
+
+    var buf: [max_bytes_header_name]u8 = undefined;
+    const lower = std.ascii.lowerString(&buf, name);
+
+    var it = self.httpz_headers.iterator();
+    while (it.next()) |header| {
+        if (std.mem.eql(u8, header.key, lower)) return true;
+    }
+    return false;
+}
+
 /// Get the first value for a given header identified by `name`, which is assumed to be lower case.
 pub fn getLower(self: Headers, name: []const u8) ?[]const u8 {
     std.debug.assert(name.len <= max_bytes_header_name);
@@ -70,6 +89,7 @@ pub fn count(self: Headers) usize {
 
 /// Add `name` and `value` to headers.
 pub fn append(self: *Headers, name: []const u8, value: []const u8) !void {
+    if (self.options.read_only) return error.JetzigReadOnlyHeaders;
     if (self.httpz_headers.len >= self.httpz_headers.keys.len) return error.JetzigTooManyHeaders;
 
     var buf: [max_bytes_header_name]u8 = undefined;
diff --git a/src/jetzig/http/Request.zig b/src/jetzig/http/Request.zig
index 2c06db1..d83f504 100644
--- a/src/jetzig/http/Request.zig
+++ b/src/jetzig/http/Request.zig
@@ -162,7 +162,7 @@ pub fn init(
 
     const response_data = try allocator.create(jetzig.data.Data);
     response_data.* = jetzig.data.Data.init(allocator);
-    const headers = jetzig.http.Headers.init(allocator, httpz_request.headers);
+    const headers = jetzig.http.Headers.init(allocator, httpz_request.headers, .{ .read_only = true });
     const host = headers.getLower("host") orelse "";
 
     return .{
diff --git a/src/jetzig/http/Response.zig b/src/jetzig/http/Response.zig
index db1e843..f08a07b 100644
--- a/src/jetzig/http/Response.zig
+++ b/src/jetzig/http/Response.zig
@@ -23,7 +23,7 @@ pub fn init(
         .httpz_response = httpz_response,
         .status_code = .no_content,
         .content = "",
-        .headers = jetzig.http.Headers.init(allocator, &httpz_response.headers),
+        .headers = jetzig.http.Headers.init(allocator, &httpz_response.headers, .{}),
     };
 }
 
diff --git a/src/jetzig/http/Server.zig b/src/jetzig/http/Server.zig
index 20bab44..aa733a3 100644
--- a/src/jetzig/http/Server.zig
+++ b/src/jetzig/http/Server.zig
@@ -184,7 +184,9 @@ pub fn RoutedServer(Routes: type) type {
             }
 
             try self.renderResponse(&request);
-            try request.response.headers.append("Content-Type", response.contentType());
+            if (!request.response.headers.has("content-type")) {
+                try request.response.headers.append("Content-Type", response.contentType());
+            }
 
             try jetzig.http.middleware.beforeResponse(&middleware_data, &request);
             try request.respond();
@@ -241,8 +243,7 @@ pub fn RoutedServer(Routes: type) type {
                 if (request.redirect_state) |state| {
                     try request.renderRedirect(state);
                 } else if (request.rendered_view) |rendered| {
-                    // TODO: Allow middleware to set content
-                    request.setResponse(.{ .view = rendered, .content = "" }, .{});
+                    request.setResponse(.{ .view = rendered, .content = rendered.content orelse "" }, .{});
                 }
                 try request.response.headers.append("Content-Type", response.contentType());
                 try request.respond();
@@ -272,7 +273,13 @@ pub fn RoutedServer(Routes: type) type {
                     };
                     request.setResponse(rendered, .{ .content_type = route.content_type });
                     return;
-                } else unreachable; // In future a MiddlewareRoute might provide a render function etc.
+                } else if (request.rendered_view) |rendered_view| {
+                    request.setResponse(
+                        .{ .view = rendered_view, .content = rendered_view.content orelse "" },
+                        .{ .content_type = route.content_type },
+                    );
+                    return;
+                }
             }
 
             const maybe_route = self.matchCustomRoute(request) orelse try self.matchRoute(request, false);
@@ -281,9 +288,7 @@ pub fn RoutedServer(Routes: type) type {
                 if (!route.validateFormat(request)) {
                     return request.setResponse(try self.renderNotFound(request), .{});
                 }
-            }
 
-            if (maybe_route) |route| {
                 for (route.before_callbacks) |callback| {
                     try callback(request, route);
                     if (request.rendered_view) |view| {
@@ -352,10 +357,9 @@ pub fn RoutedServer(Routes: type) type {
                         return request.setResponse(rendered_error, .{});
                     };
 
-                    return if (request.isRendered() or request.dynamic_assigned_template != null)
-                        request.setResponse(rendered, .{})
-                    else
-                        request.setResponse(try self.renderNotFound(request), .{});
+                    return if (request.isRendered() or request.dynamic_assigned_template != null) blk: {
+                        break :blk request.setResponse(rendered, .{});
+                    } else request.setResponse(try self.renderNotFound(request), .{});
                 }
             } else {
                 // If no matching route found, try to render a Markdown file in views directory.
@@ -425,7 +429,7 @@ pub fn RoutedServer(Routes: type) type {
                 },
                 .rendered_text => {
                     const view = request.rendered_view.?; // a panic here is a bug.
-                    return .{ .view = view, .content = request.response.content };
+                    return .{ .view = view, .content = view.content orelse request.response.content };
                 },
                 else => {},
             }
diff --git a/src/jetzig/middleware/ChannelsMiddleware.zig b/src/jetzig/middleware/ChannelsMiddleware.zig
index bef43e4..eb4b184 100644
--- a/src/jetzig/middleware/ChannelsMiddleware.zig
+++ b/src/jetzig/middleware/ChannelsMiddleware.zig
@@ -32,5 +32,6 @@ pub const Blocks = struct {
 };
 
 pub fn renderChannels(request: *jetzig.Request) !jetzig.View {
+    try request.response.headers.append("Content-Type", "text/javascript");
     return request.renderContent(.ok, @embedFile("channels/channels.js"));
 }
diff --git a/src/jetzig/middleware/channels/channels.js b/src/jetzig/middleware/channels/channels.js
index 7a16b2b..6b95344 100644
--- a/src/jetzig/middleware/channels/channels.js
+++ b/src/jetzig/middleware/channels/channels.js
@@ -180,7 +180,7 @@ const Jetzig = window.Jetzig;
       }
     });
     channel.websocket.addEventListener("open", (event) => {
-      // TODO
+      // TODO - init callback
       channel.publish("websockets", {});
     });
   };
diff --git a/src/jetzig/websockets/Websocket.zig b/src/jetzig/websockets/Websocket.zig
index 39b8f3a..75e52da 100644
--- a/src/jetzig/websockets/Websocket.zig
+++ b/src/jetzig/websockets/Websocket.zig
@@ -56,6 +56,7 @@ pub fn RoutedWebsocket(Routes: type) type {
         }
 
         pub fn afterInit(websocket: *Websocket, context: Context) !void {
+            std.debug.print("afterInit\n", .{});
             _ = context;
             if (router.encoded_params.get(websocket.route.path)) |params| {
                 var stack_fallback = std.heap.stackFallback(4096, websocket.allocator);