diff --git a/build.zig b/build.zig
index cc85cb4..8090aa9 100644
--- a/build.zig
+++ b/build.zig
@@ -1,7 +1,7 @@
 const std = @import("std");
 const build_facilio = @import("facil.io/build.zig").build_facilio;
 
-pub fn build(b: *std.build.Builder) !void {
+pub fn build(b: *std.Build) !void {
     const target = b.standardTargetOptions(.{});
     // Standard release options allow the person running `zig build` to select
     // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall.
@@ -16,12 +16,12 @@ pub fn build(b: *std.build.Builder) !void {
     };
 
     // create a module to be used internally.
-    const zap_module = b.createModule(.{
-        .source_file = .{ .path = "src/zap.zig" },
+    const zap_module = b.addModule("zap", .{
+        .root_source_file = .{ .path = "src/zap.zig" },
     });
 
     // register the module so it can be referenced using the package manager.
-    try b.modules.put(b.dupe("zap"), zap_module);
+    // try b.modules.put(b.dupe("zap"), zap_module);
 
     const facilio = try build_facilio("facil.io", b, target, optimize, use_openssl);
 
@@ -95,8 +95,8 @@ pub fn build(b: *std.build.Builder) !void {
             .optimize = optimize,
         });
 
+        example.root_module.addImport("zap", zap_module);
         example.linkLibrary(facilio);
-        example.addModule("zap", zap_module);
 
         // const example_run = example.run();
         const example_run = b.addRunArtifact(example);
@@ -131,7 +131,7 @@ pub fn build(b: *std.build.Builder) !void {
         .optimize = optimize,
     });
     auth_tests.linkLibrary(facilio);
-    auth_tests.addModule("zap", zap_module);
+    auth_tests.root_module.addImport("zap", zap_module);
 
     const run_auth_tests = b.addRunArtifact(auth_tests);
     const install_auth_tests = b.addInstallArtifact(auth_tests, .{});
@@ -144,7 +144,7 @@ pub fn build(b: *std.build.Builder) !void {
         .optimize = optimize,
     });
     mustache_tests.linkLibrary(facilio);
-    mustache_tests.addModule("zap", zap_module);
+    mustache_tests.root_module.addImport("zap", zap_module);
 
     const run_mustache_tests = b.addRunArtifact(mustache_tests);
     const install_mustache_tests = b.addInstallArtifact(mustache_tests, .{});
@@ -158,7 +158,8 @@ pub fn build(b: *std.build.Builder) !void {
     });
 
     httpparams_tests.linkLibrary(facilio);
-    httpparams_tests.addModule("zap", zap_module);
+    httpparams_tests.root_module.addImport("zap", zap_module);
+
     const run_httpparams_tests = b.addRunArtifact(httpparams_tests);
     // TODO: for some reason, tests aren't run more than once unless
     //       dependencies have changed.
@@ -175,7 +176,7 @@ pub fn build(b: *std.build.Builder) !void {
     });
 
     sendfile_tests.linkLibrary(facilio);
-    sendfile_tests.addModule("zap", zap_module);
+    sendfile_tests.root_module.addImport("zap", zap_module);
     const run_sendfile_tests = b.addRunArtifact(sendfile_tests);
     const install_sendfile_tests = b.addInstallArtifact(sendfile_tests, .{});
 
@@ -229,7 +230,7 @@ pub fn build(b: *std.build.Builder) !void {
         .optimize = optimize,
     });
     docserver_exe.linkLibrary(facilio);
-    docserver_exe.addModule("zap", zap_module);
+    docserver_exe.root_module.addImport("zap", zap_module);
     var docserver_step = b.step("docserver", "Build docserver");
     const docserver_build_step = b.addInstallArtifact(docserver_exe, .{});
     docserver_step.dependOn(&docserver_build_step.step);
diff --git a/facil.io/build.zig b/facil.io/build.zig
index 2c2fd80..690eb9a 100644
--- a/facil.io/build.zig
+++ b/facil.io/build.zig
@@ -2,11 +2,11 @@ const std = @import("std");
 
 pub fn build_facilio(
     comptime subdir: []const u8,
-    b: *std.build.Builder,
-    target: std.zig.CrossTarget,
+    b: *std.Build,
+    target: std.Build.ResolvedTarget,
     optimize: std.builtin.OptimizeMode,
     use_openssl: bool,
-) !*std.build.CompileStep {
+) !*std.Build.Step.Compile {
     const lib = b.addStaticLibrary(.{
         .name = "facil.io",
         .target = target,
@@ -15,7 +15,7 @@ pub fn build_facilio(
 
     // Generate flags
     var flags = std.ArrayList([]const u8).init(std.heap.page_allocator);
-    if (lib.optimize != .Debug) try flags.append("-Os");
+    if (optimize != .Debug) try flags.append("-Os");
     try flags.append("-Wno-return-type-c-linkage");
     try flags.append("-fno-sanitize=undefined");
 
@@ -26,7 +26,7 @@ pub fn build_facilio(
     //
 
     try flags.append("-DFIO_HTTP_EXACT_LOGGING");
-    if (target.getAbi() == .musl)
+    if (target.result.abi == .musl)
         try flags.append("-D_LARGEFILE64_SOURCE");
     if (use_openssl)
         try flags.append("-DHAVE_OPENSSL -DFIO_TLS_FOUND");
diff --git a/flake.lock b/flake.lock
index fc268f1..23ac743 100644
--- a/flake.lock
+++ b/flake.lock
@@ -92,11 +92,11 @@
       },
       "locked": {
         "dir": "contrib",
-        "lastModified": 1703884419,
-        "narHash": "sha256-Cth9deiBGnMhW0+QgaPJ/axiRZT1vGBZOlwLkquucMI=",
+        "lastModified": 1704461694,
+        "narHash": "sha256-dQc9Bkh5uf0R4po3NWnCGx+3eqOZR7iSR4jmRvNNm+E=",
         "owner": "neovim",
         "repo": "neovim",
-        "rev": "c5e9acca6471280e32fbcaa30849aa68358155ca",
+        "rev": "c509f4907bf7405c9c2ae3f7eff76c5d552944cc",
         "type": "github"
       },
       "original": {
@@ -108,11 +108,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1703875886,
-        "narHash": "sha256-WJ0s5WWOBUnXAfPwxLm0cI4XjeLXPdI95Znwjrsfd2A=",
+        "lastModified": 1704290814,
+        "narHash": "sha256-LWvKHp7kGxk/GEtlrGYV68qIvPHkU9iToomNFGagixU=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "0fce51a5077927de454b94ffae41c2749fa15ba2",
+        "rev": "70bdadeb94ffc8806c0570eb5c2695ad29f0e421",
         "type": "github"
       },
       "original": {
@@ -184,11 +184,11 @@
         "nixpkgs": "nixpkgs_2"
       },
       "locked": {
-        "lastModified": 1703636531,
-        "narHash": "sha256-gaXmic+so/NhvsXwoiM759HxE41tdFdjuepFmgXhpQE=",
+        "lastModified": 1704456535,
+        "narHash": "sha256-hR5ACOZ59qg2Ghop+fp5DJHfZHy4Mz/7xootwnVoxd0=",
         "owner": "mitchellh",
         "repo": "zig-overlay",
-        "rev": "d6cc5ac1207d2e4ae717515737fc47a705e57d76",
+        "rev": "b97c02c5de441db91f6de78db1e0077b36e3c869",
         "type": "github"
       },
       "original": {