diff --git a/src/link/Wasm.zig b/src/link/Wasm.zig
index ed07756345..da9a878720 100644
--- a/src/link/Wasm.zig
+++ b/src/link/Wasm.zig
@@ -651,7 +651,12 @@ fn resolveSymbolsInArchives(wasm: *Wasm) !void {
     }
 }
 
-fn validateFeatures(wasm: *const Wasm, arena: Allocator) !void {
+fn validateFeatures(
+    wasm: *const Wasm,
+    arena: Allocator,
+    to_emit: *[@typeInfo(std.Target.wasm.Feature).Enum.fields.len]bool,
+    emit_features_count: *u32,
+) !void {
     const cpu_features = wasm.base.options.target.cpu.features;
     const infer = cpu_features.isEmpty(); // when the user did not define any features, we infer them from linked objects.
     var allowed = std.AutoHashMap(std.Target.wasm.Feature, void).init(arena);
@@ -755,6 +760,13 @@ fn validateFeatures(wasm: *const Wasm, arena: Allocator) !void {
     if (!valid_feature_set) {
         return error.InvalidFeatureSet;
     }
+
+    if (allowed.count() > 0) {
+        emit_features_count.* = allowed.count();
+        for (to_emit) |*feature_enabled, feature_index| {
+            feature_enabled.* = allowed.contains(@intToEnum(std.Target.wasm.Feature, feature_index));
+        }
+    }
 }
 
 fn checkUndefinedSymbols(wasm: *const Wasm) !void {
@@ -2264,7 +2276,9 @@ pub fn flushModule(wasm: *Wasm, comp: *Compilation, prog_node: *std.Progress.Nod
         try wasm.resolveSymbolsInObject(@intCast(u16, object_index));
     }
 
-    try wasm.validateFeatures(arena);
+    var emit_features_count: u32 = 0;
+    var enabled_features: [@typeInfo(std.Target.wasm.Feature).Enum.fields.len]bool = undefined;
+    try wasm.validateFeatures(arena, &enabled_features, &emit_features_count);
     try wasm.resolveSymbolsInArchives();
     try wasm.checkUndefinedSymbols();
 
@@ -2710,6 +2724,9 @@ pub fn flushModule(wasm: *Wasm, comp: *Compilation, prog_node: *std.Progress.Nod
         }
 
         try emitProducerSection(&binary_bytes);
+        if (emit_features_count > 0) {
+            try emitFeaturesSection(&binary_bytes, &enabled_features, emit_features_count);
+        }
     }
 
     // Only when writing all sections executed properly we write the magic
@@ -2802,6 +2819,32 @@ fn emitProducerSection(binary_bytes: *std.ArrayList(u8)) !void {
     );
 }
 
+fn emitFeaturesSection(binary_bytes: *std.ArrayList(u8), enabled_features: []const bool, features_count: u32) !void {
+    const header_offset = try reserveCustomSectionHeader(binary_bytes);
+
+    const writer = binary_bytes.writer();
+    const target_features = "target_features";
+    try leb.writeULEB128(writer, @intCast(u32, target_features.len));
+    try writer.writeAll(target_features);
+
+    try leb.writeULEB128(writer, features_count);
+    for (enabled_features) |enabled, feature_index| {
+        if (enabled) {
+            const feature: types.Feature = .{ .prefix = .used, .tag = @intToEnum(types.Feature.Tag, feature_index) };
+            try leb.writeULEB128(writer, @enumToInt(feature.prefix));
+            const string = feature.toString();
+            try leb.writeULEB128(writer, @intCast(u32, string.len));
+            try writer.writeAll(string);
+        }
+    }
+
+    try writeCustomSectionHeader(
+        binary_bytes.items,
+        header_offset,
+        @intCast(u32, binary_bytes.items.len - header_offset - 6),
+    );
+}
+
 fn emitNameSection(wasm: *Wasm, binary_bytes: *std.ArrayList(u8), arena: std.mem.Allocator) !void {
     const Name = struct {
         index: u32,