diff --git a/lib/types/types.ww b/lib/types/types.ww
index be9df930..daa16f01 100644
--- a/lib/types/types.ww
+++ b/lib/types/types.ww
@@ -18,3 +18,10 @@ def U8_MAX:  u8  = 255;
 def U16_MAX: u16 = 65535;
 def U32_MAX: u32 = 4294967295;
 def U64_MAX: u64 = 18446744073709551615;
+
+def U8_MIN:  u8  = 0;
+def U16_MIN: u16 = 0;
+def U32_MIN: u32 = 0;
+def U64_MIN: u64 = 0;
+
+def RUNE_MIN: rune = '\0';
diff --git a/selfhost/cmd/w6a/main.combined.ww b/selfhost/cmd/w6a/main.combined.ww
index 05b22889..b899ee9b 100644
--- a/selfhost/cmd/w6a/main.combined.ww
+++ b/selfhost/cmd/w6a/main.combined.ww
@@ -771,6 +771,13 @@ def U16_MAX: u16 = 65535;
 def U32_MAX: u32 = 4294967295;
 def U64_MAX: u64 = 18446744073709551615;
 
+def U8_MIN:  u8  = 0;
+def U16_MIN: u16 = 0;
+def U32_MIN: u32 = 0;
+def U64_MIN: u64 = 0;
+
+def RUNE_MIN: rune = '\0';
+
 // bytes — slice operations over []u8. Mirrors Hare's bytes module
 // (ref/hare/bytes/) for the in-tree subset: search/equality/prefix
 // helpers used by lib/encoding, lib/bufio, lib/memio.
diff --git a/selfhost/cmd/w6c/main.combined.ww b/selfhost/cmd/w6c/main.combined.ww
index 816a4e37..f284840b 100644
--- a/selfhost/cmd/w6c/main.combined.ww
+++ b/selfhost/cmd/w6c/main.combined.ww
@@ -771,6 +771,13 @@ def U16_MAX: u16 = 65535;
 def U32_MAX: u32 = 4294967295;
 def U64_MAX: u64 = 18446744073709551615;
 
+def U8_MIN:  u8  = 0;
+def U16_MIN: u16 = 0;
+def U32_MIN: u32 = 0;
+def U64_MIN: u64 = 0;
+
+def RUNE_MIN: rune = '\0';
+
 // bytes — slice operations over []u8. Mirrors Hare's bytes module
 // (ref/hare/bytes/) for the in-tree subset: search/equality/prefix
 // helpers used by lib/encoding, lib/bufio, lib/memio.
diff --git a/selfhost/cmd/w6l/main.combined.ww b/selfhost/cmd/w6l/main.combined.ww
index 837b2a28..90daa61d 100644
--- a/selfhost/cmd/w6l/main.combined.ww
+++ b/selfhost/cmd/w6l/main.combined.ww
@@ -880,6 +880,13 @@ def U16_MAX: u16 = 65535;
 def U32_MAX: u32 = 4294967295;
 def U64_MAX: u64 = 18446744073709551615;
 
+def U8_MIN:  u8  = 0;
+def U16_MIN: u16 = 0;
+def U32_MIN: u32 = 0;
+def U64_MIN: u64 = 0;
+
+def RUNE_MIN: rune = '\0';
+
 // bytes — slice operations over []u8. Mirrors Hare's bytes module
 // (ref/hare/bytes/) for the in-tree subset: search/equality/prefix
 // helpers used by lib/encoding, lib/bufio, lib/memio.
diff --git a/selfhost/cmd/ww/main.combined.ww b/selfhost/cmd/ww/main.combined.ww
index e789cc9a..a43bb127 100644
--- a/selfhost/cmd/ww/main.combined.ww
+++ b/selfhost/cmd/ww/main.combined.ww
@@ -771,6 +771,13 @@ def U16_MAX: u16 = 65535;
 def U32_MAX: u32 = 4294967295;
 def U64_MAX: u64 = 18446744073709551615;
 
+def U8_MIN:  u8  = 0;
+def U16_MIN: u16 = 0;
+def U32_MIN: u32 = 0;
+def U64_MIN: u64 = 0;
+
+def RUNE_MIN: rune = '\0';
+
 // bytes — slice operations over []u8. Mirrors Hare's bytes module
 // (ref/hare/bytes/) for the in-tree subset: search/equality/prefix
 // helpers used by lib/encoding, lib/bufio, lib/memio.
diff --git a/selfhost/cmd/wwdump/main.combined.ww b/selfhost/cmd/wwdump/main.combined.ww
index a572cf9d..034e78a0 100644
--- a/selfhost/cmd/wwdump/main.combined.ww
+++ b/selfhost/cmd/wwdump/main.combined.ww
@@ -748,6 +748,13 @@ def U16_MAX: u16 = 65535;
 def U32_MAX: u32 = 4294967295;
 def U64_MAX: u64 = 18446744073709551615;
 
+def U8_MIN:  u8  = 0;
+def U16_MIN: u16 = 0;
+def U32_MIN: u32 = 0;
+def U64_MIN: u64 = 0;
+
+def RUNE_MIN: rune = '\0';
+
 // bytes — slice operations over []u8. Mirrors Hare's bytes module
 // (ref/hare/bytes/) for the in-tree subset: search/equality/prefix
 // helpers used by lib/encoding, lib/bufio, lib/memio.