diff --git a/lang/ott/Makefile b/lang/ott/Makefile
index a9b98f77a508..cf12e9630334 100644
--- a/lang/ott/Makefile
+++ b/lang/ott/Makefile
@@ -1,27 +1,29 @@
 PORTNAME=	ott
-PORTVERSION=	0.28
-PORTREVISION=	1
+DISTVERSION=	0.33
 CATEGORIES=	lang
 
 MAINTAINER=	domagoj.stolfa@cl.cam.ac.uk
 COMMENT=	Tool for writing definitions of programming languages and calculi
 WWW=		https://github.com/ott-lang/ott
 
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENCE
 
-USES=	gmake
+BUILD_DEPENDS=	${OCAMLFIND_DEPEND} \
+		ocaml-ocamlgraph>=0:math/ocaml-ocamlgraph
 
-ALL_TARGET=	world
+USES=		gmake
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	ott-lang
 
 USE_OCAML=	yes
 
+ALL_TARGET=	world
+
 PLIST_FILES=	bin/ott
 
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/bin/ott ${STAGEDIR}${PREFIX}/bin
 
 .include <bsd.port.mk>
diff --git a/lang/ott/distinfo b/lang/ott/distinfo
index 1313a4ff43b9..ee2894ac8018 100644
--- a/lang/ott/distinfo
+++ b/lang/ott/distinfo
@@ -1,3 +1,3 @@
-TIMESTAMP = 1537137485
-SHA256 (ott-lang-ott-0.28_GH0.tar.gz) = 30c7613802cdd7f03eb1df1d634da3e13197e210d5697252382d29b5f03618f2
-SIZE (ott-lang-ott-0.28_GH0.tar.gz) = 3263773
+TIMESTAMP = 1718314215
+SHA256 (ott-lang-ott-0.33_GH0.tar.gz) = d64ec4527f8ace56a407fc67957840d1653980fb0112d7fa8f2b0fc958501f7b
+SIZE (ott-lang-ott-0.33_GH0.tar.gz) = 3533658