diff --git a/doc/Peg.md b/doc/Peg.md
index c57a3dda..93a04489 100644
--- a/doc/Peg.md
+++ b/doc/Peg.md
@@ -109,6 +109,8 @@ can be thought of as the looping and branching forms in a traditional language
 | `(! patt)`   | Alias for `(not patt)` |
 | `(look offset patt)` | Matches only if patt matches at a fixed offset. offset can be any integer. patt will not produce captures and the peg will not advance any characters. |
 | `(> offset patt)` | Alias for `(look offset patt)` |
+| `(opt patt)` | Alias for `(between 0 1 patt)` |
+| `(? patt)` | Alias for `(between 0 1 patt)` |
 
 PEGs try to match an input text with a pattern in a greedy manner.
 This means that if a rule fails to match, that rule will fail and not try again. The only
diff --git a/src/core/peg.c b/src/core/peg.c
index ca1ce448..551a2452 100644
--- a/src/core/peg.c
+++ b/src/core/peg.c
@@ -713,7 +713,6 @@ static void spec_replace(Builder *b, int32_t argc, const Janet *argv) {
     emit_2(r, RULE_REPLACE, subrule, constant);
 }
 
-/* For some and any, really just short-hand for (^ rule n) */
 static void spec_repeater(Builder *b, int32_t argc, const Janet *argv, int32_t min) {
     peg_fixarity(b, argc, 1);
     Reserve r = reserve(b, 4);
@@ -744,6 +743,13 @@ static void spec_atmost(Builder *b, int32_t argc, const Janet *argv) {
     emit_3(r, RULE_BETWEEN, 0, n, subrule);
 }
 
+static void spec_opt(Builder *b, int32_t argc, const Janet *argv) {
+    peg_fixarity(b, argc, 1);
+    Reserve r = reserve(b, 4);
+    uint32_t subrule = compile1(b, argv[0]);
+    emit_3(r, RULE_BETWEEN, 0, 1, subrule);
+}
+
 static void spec_matchtime(Builder *b, int32_t argc, const Janet *argv) {
     peg_fixarity(b, argc, 2);
     Reserve r = reserve(b, 3);
@@ -773,6 +779,7 @@ static const SpecialPair specials[] = {
     {"/", spec_replace},
     {"<-", spec_capture},
     {">", spec_look},
+    {"?", spec_opt},
     {"any", spec_any},
     {"argument", spec_argument},
     {"at-least", spec_atleast},
@@ -788,6 +795,7 @@ static const SpecialPair specials[] = {
     {"if-not", spec_ifnot},
     {"look", spec_look},
     {"not", spec_not},
+    {"opt", spec_opt},
     {"position", spec_position},
     {"range", spec_range},
     {"replace", spec_replace},
diff --git a/test/suite3.janet b/test/suite3.janet
index 4c98385a..acf002be 100644
--- a/test/suite3.janet
+++ b/test/suite3.janet
@@ -319,4 +319,13 @@
 (check-match janet-longstring "``` `` ```" true)
 (check-match janet-longstring "``  ```" false)
 
+# Optional
+
+(check-match '(* (opt "hi") -1) "" true)
+(check-match '(* (opt "hi") -1) "hi" true)
+(check-match '(* (opt "hi") -1) "no" false)
+(check-match '(* (? "hi") -1) "" true)
+(check-match '(* (? "hi") -1) "hi" true)
+(check-match '(* (? "hi") -1) "no" false)
+
 (end-suite)