diff --git a/kraken.krak b/kraken.krak
index 37b0f39..28b89c8 100644
--- a/kraken.krak
+++ b/kraken.krak
@@ -22,9 +22,14 @@ fun main(argc: int, argv: **char):int {
     }
     var input_file_offset = 1
     var interpret_instead = false
-    if (string(argv[1]) == "-i") {
+    var argv1_str = string(argv[1])
+    var opt_str = string("-O3")
+    if (argv1_str == "-i") {
         interpret_instead = true
         input_file_offset++
+    } else if (argv1_str.length() > 2 && argv1_str.slice(0,2) == "-O") {
+        opt_str = argv1_str
+        input_file_offset++
     }
     var kraken_file_name = string(argv[input_file_offset])
     var executable_name = string(".").join(kraken_file_name.split('.').slice(0,-2))
@@ -87,7 +92,7 @@ fun main(argc: int, argv: **char):int {
         var kraken_c_output_name = kraken_file_name + ".c"
         write_file(kraken_c_output_name, c_output_pair.first)
         /*println(string("linker string: ") + c_output_pair.second)*/
-        var compile_string = "cc -g -O3 -Wno-int-to-pointer-cast -Wno-pointer-to-int-cast -std=c99 " + c_output_pair.second + " " + kraken_c_output_name + " -o " + executable_name
+        var compile_string = "cc -g " + opt_str + " -Wno-int-to-pointer-cast -Wno-pointer-to-int-cast -std=c99 " + c_output_pair.second + " " + kraken_c_output_name + " -o " + executable_name
         printlnerr(compile_string)
         system(compile_string)
     }