diff --git a/bootstrap/src/hmc/Grammar.hmh b/bootstrap/src/hmc/Grammar.hmh
new file mode 100644
index 00000000..81ad14a7
--- /dev/null
+++ b/bootstrap/src/hmc/Grammar.hmh
@@ -0,0 +1,9 @@
+open Basis
+open! Basis.Rudiments
+
+type token_and = {source: Source.Slice.t}
+
+include hocc
+    token AND "and" of token_and
+
+    start S ::= epsilon
diff --git a/bootstrap/src/hmc/Grammar.hmhi b/bootstrap/src/hmc/Grammar.hmhi
new file mode 100644
index 00000000..69a2c110
--- /dev/null
+++ b/bootstrap/src/hmc/Grammar.hmhi
@@ -0,0 +1,6 @@
+open Basis
+open! Basis.Rudiments
+
+type token_and = {source: Source.Slice.t}
+
+include hocc
diff --git a/bootstrap/src/hmc/dune b/bootstrap/src/hmc/dune
index dd23e576..e3002e93 100644
--- a/bootstrap/src/hmc/dune
+++ b/bootstrap/src/hmc/dune
@@ -4,3 +4,13 @@
  (libraries Basis)
  (synopsis "Hemlock bootstrap compiler library")
  )
+
+; This rule calls an out-of-tree `hocc`, because the in-tree one depends on `Hmc`.
+(rule
+ (deps
+  (glob_files Grammar.hmh*))
+ (targets Grammar.mli Grammar.ml)
+ (action
+  (with-accepted-exit-codes
+   (or 0 1)
+   (system "hocc -v -a ielr1 -ml -s Grammar"))))