diff --git a/compiler/src/thrift.l b/compiler/src/thrift.l
new file mode 100644
index 0000000..5164c89
--- /dev/null
+++ b/compiler/src/thrift.l
@@ -0,0 +1,59 @@
+/**
+ * Thrift scanner.
+ * 
+ * Tokenizes a thrift definition file.
+ * @author Mark Slee <mcslee@facebook.com>
+ */
+%{
+
+#include "main.h"
+#include "parse/t_program.h"
+
+/** Must be included AFTER parse/t_program.h */
+#include "thrift.tab.hh"
+
+%}
+
+/** Provides yylineno global */
+%option lex-compat 	
+
+/** Helper definitions */
+intconstant  ([0-9]+)
+identifier   ([a-zA-Z_][a-zA-Z_0-9]*)
+whitespace   ([ \t\r\n]*)
+multicomm    ("/*""/"*([^*/]|[^*]"/"|"*"[^/])*"*"*"*/")
+comment      ("//"[^\n]*)
+symbol       ([\,\{\}\(\)\=])
+
+%%
+
+{whitespace}  { /* do nothing */ }
+{multicomm}   { /* do nothing */ }
+{comment}     { /* do nothing */ }
+
+{symbol}      { return yytext[0];   }
+
+"byte"        { return tok_byte;     }
+"string"      { return tok_string;   }
+"i32"         { return tok_i32;      }
+"u32"         { return tok_u32;      }
+"i64"         { return tok_i64;      }
+"u64"         { return tok_u64;      }
+
+"map"         { return tok_map;      }
+"list"        { return tok_list;     }
+"set"         { return tok_set;      }
+
+"void"        { return tok_void;     }
+"async"       { return tok_async;    }
+
+"typedef"     { return tok_typedef;  }
+"struct"      { return tok_struct;   }
+"function"    { return tok_function; }
+"service"     { return tok_service;  }
+"enum"        { return tok_enum;     }
+
+{intconstant} { yylval.iconst = atoi(yytext) ; return tok_int_constant; }
+{identifier}  { yylval.id = strdup(yytext); return tok_identifier; }
+
+%%