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diff --git a/src/compat.zig b/src/compat.zig
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+/// Compatibility support for very old versions of Zig and recent versions before
+/// commit efa25e7d5 (Merge pull request #14498 from ziglang/zig-build-api).
+///
+/// Versions of Zig from before 0.6.0 cannot do the version check and will just
+/// fail to compile, but 0.5.0 was a long time ago, it is unlikely that anyone
+/// who attempts these exercises is still using it.
+const std = @import("std");
+const builtin = @import("builtin");
+
+const debug = std.debug;
+
+// Very old versions of Zig used warn instead of print.
+const print = if (@hasDecl(debug, "print")) debug.print else debug.warn;
+
+// When changing this version, be sure to also update README.md in two places:
+//     1) Getting Started
+//     2) Version Changes
+const needed_version_str = "0.11.0-dev.2401";
+
+fn isCompatible() bool {
+    if (!@hasDecl(builtin, "zig_version") or !@hasDecl(std, "SemanticVersion")) {
+        return false;
+    }
+
+    const needed_version = std.SemanticVersion.parse(needed_version_str) catch unreachable;
+    const version = builtin.zig_version;
+    const order = version.order(needed_version);
+
+    return order != .lt;
+}
+
+pub fn die() noreturn {
+    const error_message =
+        \\ERROR: Sorry, it looks like your version of zig is too old. :-(
+        \\
+        \\Ziglings requires development build
+        \\
+        \\    {s}
+        \\
+        \\or higher. Please download a development ("master") build from
+        \\
+        \\    https://ziglang.org/download/
+        \\
+        \\
+    ;
+
+    print(error_message, .{needed_version_str});
+
+    // Use exit code 2, to differentiate from a normal Zig compiler error.
+    std.os.exit(2);
+}
+
+// A separate function is required because very old versions of Zig doesn't
+// support labeled block expressions.
+pub const is_compatible: bool = isCompatible();
+
+/// This is the type to be used only for the build function definition, since
+/// the type must be compatible with the build runner.
+///
+/// Don't use std.Build.Builder, since it is deprecated and may be removed in
+/// future.
+pub const Build = if (is_compatible) std.Build else std.build.Builder;
+
+/// This is the type to be used for accessing the build namespace.
+pub const build = if (is_compatible) std.Build else std.build;