diff --git a/builtin-benchmarks/foldl.jsonnet b/builtin-benchmarks/foldl.jsonnet
new file mode 100644
index 0000000..7acd4e0
--- /dev/null
+++ b/builtin-benchmarks/foldl.jsonnet
@@ -0,0 +1,3 @@
+local input = std.makeArray(10000, function(i) 'xxxxx');
+
+std.foldl(function(acc, value) acc + value, input, '')
diff --git a/builtins_benchmark_test.go b/builtins_benchmark_test.go
index aa2926c..dcaaafb 100644
--- a/builtins_benchmark_test.go
+++ b/builtins_benchmark_test.go
@@ -67,3 +67,7 @@ func Benchmark_Builtin_comparison(b *testing.B) {
 func Benchmark_Builtin_comparison2(b *testing.B) {
 	RunBenchmark(b, "comparison2")
 }
+
+func Benchmark_Builtin_foldl(b *testing.B) {
+	RunBenchmark(b, "foldl")
+}