diff --git a/frontend/cmd/cmd.h b/frontend/cmd/cmd.h
index df18463..86d6439 100644
--- a/frontend/cmd/cmd.h
+++ b/frontend/cmd/cmd.h
@@ -6,6 +6,7 @@ enum command_id {
 	CMD_ASSEMBLE,
 	CMD_COMPILE,
 	CMD_REPL,
+	CMD_INTERNAL,
 };
 
 #endif
diff --git a/frontend/cmd/internal.c b/frontend/cmd/internal.c
new file mode 100644
index 0000000..e1797ea
--- /dev/null
+++ b/frontend/cmd/internal.c
@@ -0,0 +1,60 @@
+#include <blue/cmd.h>
+#include "cmd.h"
+#include <ivy/lang/lex.h>
+#include <ivy/lang/internal.h>
+#include <blue/term.h>
+
+enum {
+	OPT_PRINT_SYMBOLS = 0x1000,
+	OPT_PRINT_KEYWORDS,
+};
+
+static int internal(const b_command *cmd, const b_arglist *args, const b_array *_)
+{
+	struct ivy_lexer *lex;
+	enum ivy_status status = ivy_lexer_create(&lex);
+	
+	if (status != IVY_OK) {
+		b_err("failed to initialise lexer (error %s)",
+		      ivy_status_to_string(status));
+		return -1;
+	}
+
+	if (b_arglist_get_count(args, OPT_PRINT_SYMBOLS, B_COMMAND_INVALID_ID)) {
+		internal_lexer_print_symbol_tree(lex);
+	}
+
+	if (b_arglist_get_count(args, OPT_PRINT_KEYWORDS, B_COMMAND_INVALID_ID)) {
+		internal_lexer_print_keyword_dict(lex);
+	}
+
+	ivy_lexer_destroy(lex);
+
+	return 0;
+}
+
+B_COMMAND(CMD_INTERNAL, CMD_ROOT)
+{
+	B_COMMAND_NAME("internal");
+	B_COMMAND_SHORT_NAME('X');
+	B_COMMAND_DESC("internal frontend debugging tools.");
+	B_COMMAND_FUNCTION(internal);
+
+	B_COMMAND_OPTION(OPT_PRINT_SYMBOLS)
+	{
+		B_OPTION_LONG_NAME("print-symbols");
+		B_OPTION_SHORT_NAME('s');
+		B_OPTION_DESC(
+			"print the symbol tree used by the language lexer.");
+	}
+
+	B_COMMAND_OPTION(OPT_PRINT_KEYWORDS)
+	{
+		B_OPTION_LONG_NAME("print-keywords");
+		B_OPTION_SHORT_NAME('k');
+		B_OPTION_DESC(
+			"print the keyword dictionary used by the language lexer.");
+	}
+
+	B_COMMAND_HELP_OPTION();
+}