diff --git a/README.md b/README.md
index 05a13cc7b011030984ef8c9914e798529b327024..d1a634f3d3f8e163ba5ea1e0435c67643c5b05ab 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 ![loc](https://sloc.xyz/github/nektro/zig-oauth2)
 [![license](https://img.shields.io/github/license/nektro/zig-oauth2.svg)](https://github.com/nektro/zig-oauth2/blob/master/LICENSE)
 [![nektro @ github sponsors](https://img.shields.io/badge/sponsors-nektro-purple?logo=github)](https://github.com/sponsors/nektro)
-[![Zig](https://img.shields.io/badge/Zig-0.15-f7a41d)](https://ziglang.org/)
+[![Zig](https://img.shields.io/badge/Zig-0.16-f7a41d)](https://ziglang.org/)
 [![Zigmod](https://img.shields.io/badge/Zigmod-latest-f7a41d)](https://github.com/nektro/zigmod)
 
 HTTP handler functions to allow you to easily add OAuth2 login support to your Zig application.
diff --git a/build.zig b/build.zig
index c8b2f465b5dea81068c5ee06448be09756f48b84..691ea5f05fe8afee54f787f133ee48b396977f8f 100644
--- a/build.zig
+++ b/build.zig
@@ -14,7 +14,7 @@ pub fn build(b: *std.Build) void {
         }),
     });
     deps.addAllTo(tests);
-    tests.linkLibC();
+    tests.root_module.link_libc = true;
     tests.use_llvm = !disable_llvm;
     tests.use_lld = !disable_llvm;
     b.getInstallStep().dependOn(&tests.step);
diff --git a/oauth2.zig b/oauth2.zig
index d53e23bb76877e7aca413e78ffe687b0b25fb94e..258697eb47386b7d0a1348b89dc3914acf3d4f42 100644
--- a/oauth2.zig
+++ b/oauth2.zig
@@ -9,6 +9,8 @@ const url = @import("url");
 const http = @import("http");
 const nio = @import("nio");
 const json = @import("json");
+const builtin = @import("builtin");
+const root = @import("root");
 const Base = @This();
 
 pub const Provider = struct {
@@ -266,11 +268,6 @@ pub fn clientByProviderId(clients: []const Client, name: string) ?Client {
 }
 
 pub fn Handlers(comptime T: type) type {
-    comptime std.debug.assert(@hasDecl(T, "isLoggedIn"));
-    comptime std.debug.assert(@hasDecl(T, "doneUrl"));
-    comptime std.debug.assert(@hasDecl(T, "saveInfo"));
-    comptime std.debug.assert(@hasDecl(T, "callbackPath"));
-
     return struct {
         const Self = @This();
         pub var clients: []Client = &.{};
@@ -298,8 +295,9 @@ pub fn Handlers(comptime T: type) type {
             const client = clientByProviderId(Self.clients, state) orelse return try fail(response_status, body_writer, "error: No handler found for provider: {s}\n", .{state});
             const code = query.get("code") orelse return try fail(response_status, body_writer, "", .{});
 
+            const io = if (!builtin.is_test) root.io else std.Options.debug_io;
             var buf: [4096]u8 = @splat(0);
-            var http_client: std.http.Client = .{ .allocator = alloc };
+            var http_client: std.http.Client = .{ .allocator = alloc, .io = io };
             defer http_client.deinit();
 
             var params = url.SearchParams.init(alloc);
diff --git a/test.zig b/test.zig
index 1fa8d9433083b22b6f6589f8d0b9926262558e8e..4d20bdde09fb73536274f25408e109a0edb805d4 100644
--- a/test.zig
+++ b/test.zig
@@ -1,7 +1,32 @@
 const std = @import("std");
 const oauth2 = @import("oauth2");
+const nio = @import("nio");
+const http = @import("http");
+const json = @import("json");
 
-// TODO: how do we make this better?
 test {
-    std.testing.refAllDeclsRecursive(oauth2);
+    _ = &oauth2.Provider;
+    _ = &oauth2.Client;
+    std.testing.refAllDecls(oauth2.providers);
+    std.testing.refAllDecls(oauth2.dynamic_providers);
+    _ = &oauth2.providerById;
+    _ = &oauth2.clientByProviderId;
+    _ = &oauth2.pek_domain;
+}
+test {
+    const S = struct {
+        pub const callbackPath = "/-/callback";
+        pub const doneUrl = "/";
+
+        pub fn isLoggedIn(_: *http.ServerRequest, _: std.mem.Allocator) !bool {
+            return false;
+        }
+        pub fn saveInfo(_: *http.HeadersMap, _: std.mem.Allocator, _: oauth2.Provider, _: []const u8, _: []const u8, _: json.Document, _: json.Document) !void {
+            //
+        }
+    };
+    const H = oauth2.Handlers(S);
+    std.testing.refAllDecls(oauth2.Handlers(S));
+    _ = @TypeOf(H.login(undefined, nio.NullWriter{}, undefined, undefined, undefined, undefined, undefined));
+    _ = @TypeOf(H.callback(undefined, nio.NullWriter{}, undefined, undefined, undefined, undefined, undefined));
 }
diff --git a/zig.mod b/zig.mod
index cc1473b87db0e338c02b190ab10b1d27fdcfb2db..089e315eef3c21979fd7c1c640c9b1c859401e51 100644
--- a/zig.mod
+++ b/zig.mod
@@ -12,3 +12,7 @@ dependencies:
   - src: git https://github.com/nektro/zig-net-http
   - src: git https://github.com/nektro/zig-nio
   - src: git https://github.com/nektro/zig-json
+root_dependencies:
+  - src: git https://github.com/nektro/zig-nio
+  - src: git https://github.com/nektro/zig-net-http
+  - src: git https://github.com/nektro/zig-json