diff --git a/tiny/lisp-nontail.c b/tiny/lisp-nontail.c
index d115eb2..7239ed5 100644
--- a/tiny/lisp-nontail.c
+++ b/tiny/lisp-nontail.c
@@ -26,8 +26,13 @@
 #include <ctype.h>
 #include <sys/types.h>
 
+#ifdef __LP64__
+typedef u_int64_t value_t;
+typedef int64_t number_t;
+#else
 typedef u_int32_t value_t;
 typedef int32_t number_t;
+#endif
 
 typedef struct {
     value_t car;
diff --git a/tiny/lisp2.c b/tiny/lisp2.c
index 3fb68c0..a705041 100644
--- a/tiny/lisp2.c
+++ b/tiny/lisp2.c
@@ -47,8 +47,13 @@
 #include <ctype.h>
 #include <sys/types.h>
 
+#ifdef __LP64__
+typedef u_int64_t value_t;
+typedef int64_t number_t;
+#else
 typedef u_int32_t value_t;
 typedef int32_t number_t;
+#endif
 
 typedef struct {
     value_t car;
diff --git a/tiny/lispf.c b/tiny/lispf.c
index 61c6e40..43feb1a 100644
--- a/tiny/lispf.c
+++ b/tiny/lispf.c
@@ -32,12 +32,21 @@
 #include <ctype.h>
 #include <sys/types.h>
 
+#ifdef __LP64__
+typedef u_int64_t value_t;
+#else
 typedef u_int32_t value_t;
+#endif
+
 #ifdef FLOAT
 typedef float number_t;
 #else
+#ifdef __LP64__
+typedef int64_t number_t;
+#else
 typedef int32_t number_t;
 #endif
+#endif
 
 typedef struct {
     value_t car;