diff --git a/build.zig b/build.zig
index b0938b9..884b675 100644
--- a/build.zig
+++ b/build.zig
@@ -121,15 +121,15 @@ fn makeSQLiteLib(b: *std.Build, dep: *std.Build.Dependency, c_flags: []const []c
         .root_module = mod,
     });
 
-    lib.addIncludePath(dep.path("."));
-    lib.addIncludePath(b.path("c"));
+    lib.root_module.addIncludePath(dep.path("."));
+    lib.root_module.addIncludePath(b.path("c"));
     if (sqlite_c == .with) {
-        lib.addCSourceFile(.{
+        lib.root_module.addCSourceFile(.{
             .file = dep.path("sqlite3.c"),
             .flags = c_flags,
         });
     }
-    lib.addCSourceFile(.{
+    lib.root_module.addCSourceFile(.{
         .file = b.path("c/workaround.c"),
         .flags = c_flags,
     });
@@ -242,9 +242,9 @@ pub fn build(b: *std.Build) !void {
             .name = test_name,
             .root_module = mod,
         });
-        tests.addIncludePath(b.path("c"));
-        tests.addIncludePath(sqlite_dep.path("."));
-        tests.linkLibrary(test_sqlite_lib);
+        tests.root_module.addIncludePath(b.path("c"));
+        tests.root_module.addIncludePath(sqlite_dep.path("."));
+        tests.root_module.linkLibrary(test_sqlite_lib);
 
         const tests_options = b.addOptions();
         tests.root_module.addImport("build_options", tests_options.createModule());
@@ -367,6 +367,7 @@ const PreprocessStep = struct {
     fn make(step: *std.Build.Step, _: std.Build.Step.MakeOptions) !void {
         const ps: *PreprocessStep = @fieldParentPtr("step", step);
         const owner = step.owner;
+        var threaded: std.Io.Threaded = .init_single_threaded;
 
         const sqlite3_h = try ps.source.path(owner, "sqlite3.h").getPath3(owner, step).toString(owner.allocator);
         const sqlite3ext_h = try ps.source.path(owner, "sqlite3ext.h").getPath3(owner, step).toString(owner.allocator);
@@ -374,7 +375,7 @@ const PreprocessStep = struct {
         const loadable_sqlite3_h = try ps.target.path(owner, "loadable-ext-sqlite3.h").getPath3(owner, step).toString(owner.allocator);
         const loadable_sqlite3ext_h = try ps.target.path(owner, "loadable-ext-sqlite3ext.h").getPath3(owner, step).toString(owner.allocator);
 
-        try Preprocessor.sqlite3(owner.allocator, sqlite3_h, loadable_sqlite3_h);
-        try Preprocessor.sqlite3ext(owner.allocator, sqlite3ext_h, loadable_sqlite3ext_h);
+        try Preprocessor.sqlite3(owner.allocator, threaded.io(), sqlite3_h, loadable_sqlite3_h);
+        try Preprocessor.sqlite3ext(owner.allocator, threaded.io(), sqlite3ext_h, loadable_sqlite3ext_h);
     }
 };
diff --git a/build/Preprocessor.zig b/build/Preprocessor.zig
index f3d0dc6..19100b8 100644
--- a/build/Preprocessor.zig
+++ b/build/Preprocessor.zig
@@ -1,6 +1,7 @@
 const std = @import("std");
 const debug = std.debug;
 const mem = std.mem;
+const Io = std.Io;
 
 // This tool is used to preprocess the sqlite3 headers to make them usable to build loadable extensions.
 //
@@ -24,11 +25,11 @@ const mem = std.mem;
 // This works but it requires fairly extensive modifications of both sqlite3.h and sqlite3ext.h which is time consuming to do manually;
 // this tool is intended to automate all these modifications.
 
-fn readOriginalData(allocator: mem.Allocator, path: []const u8) ![]const u8 {
-    var file = try std.fs.cwd().openFile(path, .{});
-    defer file.close();
+fn readOriginalData(allocator: mem.Allocator, io: Io, path: []const u8) ![]const u8 {
+    var file = try std.Io.Dir.cwd().openFile(io, path, .{});
+    defer file.close(io);
     var buf: [1024]u8 = undefined;
-    var reader = file.reader(&buf);
+    var reader = file.reader(io, &buf);
 
     const data = reader.interface.readAlloc(allocator, 1024 * 1024);
     return data;
@@ -153,8 +154,8 @@ const Processor = struct {
     }
 };
 
-pub fn sqlite3(allocator: mem.Allocator, input_path: []const u8, output_path: []const u8) !void {
-    const data = try readOriginalData(allocator, input_path);
+pub fn sqlite3(allocator: mem.Allocator, io: Io, input_path: []const u8, output_path: []const u8) !void {
+    const data = try readOriginalData(allocator, io, input_path);
 
     var processor = try Processor.init(allocator, data);
 
@@ -192,17 +193,17 @@ pub fn sqlite3(allocator: mem.Allocator, input_path: []const u8, output_path: []
 
     // Write the result
 
-    var output_file = try std.fs.cwd().createFile(output_path, .{ .mode = 0o0644 });
-    defer output_file.close();
-
-    try output_file.writeAll("/* sqlite3.h edited by the zig-sqlite build script */\n");
+    var output_file = try std.Io.Dir.cwd().createFile(io, output_path, .{}); // FIXME: Can't set .mode as an octal. Is it really necessary to have it 0644 instead of 0666?
+    defer output_file.close(io);
     var buf: [1024]u8 = undefined;
-    var out_writer = output_file.writer(&buf);
+    var out_writer = output_file.writer(io, &buf);
+    try out_writer.interface.writeAll("/* sqlite3.h edited by the zig-sqlite build script */\n");
+
     try processor.dump(&out_writer);
 }
 
-pub fn sqlite3ext(allocator: mem.Allocator, input_path: []const u8, output_path: []const u8) !void {
-    const data = try readOriginalData(allocator, input_path);
+pub fn sqlite3ext(allocator: mem.Allocator, io: Io, input_path: []const u8, output_path: []const u8) !void {
+    const data = try readOriginalData(allocator, io, input_path);
 
     var processor = try Processor.init(allocator, data);
 
@@ -230,11 +231,11 @@ pub fn sqlite3ext(allocator: mem.Allocator, input_path: []const u8, output_path:
 
     // Write the result
 
-    var output_file = try std.fs.cwd().createFile(output_path, .{ .mode = 0o0644 });
-    defer output_file.close();
+    var output_file = try std.Io.Dir.cwd().createFile(io, output_path, .{}); // FIXME: Can't set .mode as an octal. Is it really necessary to have it 0644 instead of 0666?
 
-    try output_file.writeAll("/* sqlite3ext.h edited by the zig-sqlite build script */\n");
+    defer output_file.close(io);
     var buf: [1024]u8 = undefined;
-    var out_writer = output_file.writer(&buf);
+    var out_writer = output_file.writer(io, &buf);
+    try out_writer.interface.writeAll("/* sqlite3ext.h edited by the zig-sqlite build script */\n");
     try processor.dump(&out_writer);
 }
diff --git a/query.zig b/query.zig
index 3f33e08..d430ad8 100644
--- a/query.zig
+++ b/query.zig
@@ -161,21 +161,8 @@ pub fn ParsedQuery(comptime tmp_query: []const u8) type {
                     .bind_marker_type => switch (c) {
                         '}' => {
                             state = .start;
-
                             const type_info_string = current_bind_marker_type[0..current_bind_marker_type_pos];
-                            // Handles optional types
-                            const typ = if (type_info_string[0] == '?') blk: {
-                                const child_type = ParseType(type_info_string[1..]);
-                                break :blk @Type(std.builtin.Type{
-                                    .optional = .{
-                                        .child = child_type,
-                                    },
-                                });
-                            } else blk: {
-                                break :blk ParseType(type_info_string);
-                            };
-
-                            tmp_bind_markers[nb_tmp_bind_markers].typed = typ;
+                            tmp_bind_markers[nb_tmp_bind_markers].typed = ParseType(type_info_string);
                             nb_tmp_bind_markers += 1;
                         },
                         else => {
@@ -222,18 +209,18 @@ pub fn ParsedQuery(comptime tmp_query: []const u8) type {
 fn ParseType(comptime type_info: []const u8) type {
     if (type_info.len <= 0) @compileError("invalid type info " ++ type_info);
 
+    if (type_info[0] == '?') {
+        const parsed_type = ParseType(type_info[1..]);
+        return ?parsed_type;
+    }
+
     // Integer
     if (mem.eql(u8, "usize", type_info)) return usize;
     if (mem.eql(u8, "isize", type_info)) return isize;
 
     if (type_info[0] == 'u' or type_info[0] == 'i') {
-        return @Type(std.builtin.Type{
-            .int = std.builtin.Type.Int{
-                .signedness = if (type_info[0] == 'i') .signed else .unsigned,
-                .bits = std.fmt.parseInt(usize, type_info[1..type_info.len], 10) catch {
-                    @compileError("invalid type info " ++ type_info);
-                },
-            },
+        return @Int(if (type_info[0] == 'i') .signed else .unsigned, std.fmt.parseInt(usize, type_info[1..type_info.len], 10) catch {
+            @compileError("invalid type info " ++ type_info);
         });
     }
 
diff --git a/sqlite.zig b/sqlite.zig
index dcf05a1..5d7ac10 100644
--- a/sqlite.zig
+++ b/sqlite.zig
@@ -1470,7 +1470,7 @@ pub fn Iterator(comptime Type: type) type {
                     },
                     inline .@"struct", .@"union" => |TI| {
                         if (TI.layout == .@"packed" and !@hasField(FieldType, "readField")) {
-                            const Backing = @Type(.{ .int = .{ .signedness = .unsigned, .bits = @bitSizeOf(FieldType) } });
+                            const Backing = @Int(.unsigned, @bitSizeOf(FieldType));
                             return @bitCast(self.readInt(Backing, i));
                         }
 
@@ -1701,7 +1701,7 @@ pub const DynamicStatement = struct {
                 },
                 .@"union" => |info| {
                     if (info.layout == .@"packed") {
-                        const Backing = @Type(.{ .int = .{ .signedness = .unsigned, .bits = @bitSizeOf(FieldType) } });
+                        const Backing = @Int(.unsigned, @bitSizeOf(FieldType));
                         try self.bindField(Backing, options, field_name, i, @as(Backing, @bitCast(field)));
                         return;
                     }