Index: Mk/Uses/cargo.mk
===================================================================
--- Mk/Uses/cargo.mk
+++ Mk/Uses/cargo.mk
@@ -46,7 +46,7 @@
 
 CARGO_BUILDDEP?=	yes
 .if ${CARGO_BUILDDEP:tl} == "yes"
-BUILD_DEPENDS+=	 rust>=1.31.0:lang/rust
+BUILD_DEPENDS+=	${RUST_DEFAULT}>=1.31.0:lang/${RUST_DEFAULT}
 .endif
 
 # Location of cargo binary (default to lang/rust's Cargo binary)
Index: Mk/bsd.default-versions.mk
===================================================================
--- Mk/bsd.default-versions.mk
+++ Mk/bsd.default-versions.mk
@@ -88,6 +88,8 @@
 PYTHON3_DEFAULT?=	3.6
 # Possible values: 2.3, 2.4, 2.5
 RUBY_DEFAULT?=		2.4
+# Possible values: rust, rust-nightly
+RUST_DEFAULT?=		rust
 # Possible values: 4.6, 4.7, 4.8
 SAMBA_DEFAULT?=		4.7
 # Possible values: base, openssl, openssl111, libressl, libressl-devel
Index: Mk/bsd.gecko.mk
===================================================================
--- Mk/bsd.gecko.mk
+++ Mk/bsd.gecko.mk
@@ -339,8 +339,7 @@
 .endif
 
 .if ${PORT_OPTIONS:MRUST} || ${MOZILLA_VER:R:R} >= 54
-BUILD_DEPENDS+=	${RUST_PORT:T}>=1.29:${RUST_PORT}
-RUST_PORT?=		lang/rust
+BUILD_DEPENDS+=	${RUST_DEFAULT}>=1.29:lang/${RUST_DEFAULT}
 . if ${MOZILLA_VER:R:R} < 54
 MOZ_OPTIONS+=	--enable-rust
 . endif
Index: devel/rust-cbindgen/Makefile
===================================================================
--- devel/rust-cbindgen/Makefile
+++ devel/rust-cbindgen/Makefile
@@ -12,7 +12,7 @@
 
 LICENSE=	MPL20
 
-RUN_DEPENDS=	cargo:lang/rust
+RUN_DEPENDS=	cargo:lang/${RUST_DEFAULT}
 
 USES=		cargo
 USE_GITHUB=	yes
Index: net-im/fractal/Makefile
===================================================================
--- net-im/fractal/Makefile
+++ net-im/fractal/Makefile
@@ -13,7 +13,7 @@
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 
 # gmake for the backtrace-sys crate
-BUILD_DEPENDS=	cargo:lang/rust \
+BUILD_DEPENDS=	cargo:lang/${RUST_DEFAULT} \
 		gmake:devel/gmake
 LIB_DEPENDS=	libdbus-1.so:devel/dbus \
 		libgmp.so:math/gmp \
Index: security/kr/Makefile
===================================================================
--- security/kr/Makefile
+++ security/kr/Makefile
@@ -13,7 +13,7 @@
 NOT_FOR_ARCHS=	i386
 NOT_FOR_ARCHS_REASON=	Uses 64bit types
 
-BUILD_DEPENDS=	rust>=1.19.0_2:lang/rust \
+BUILD_DEPENDS=	${RUST_DEFAULT}>=1.19.0_2:lang/${RUST_DEFAULT} \
 		bash>0:shells/bash
 
 USES=		gmake go shebangfix
Index: security/suricata/Makefile
===================================================================
--- security/suricata/Makefile
+++ security/suricata/Makefile
@@ -112,7 +112,7 @@
 				--with-libhiredis-includes=${LOCALBASE}/include \
 				--with-libhiredis-libraries=${LOCALBASE}/lib
 
-RUST_BUILD_DEPENDS=		rustc:lang/rust
+RUST_BUILD_DEPENDS=		rustc:lang/${RUST_DEFAULT}
 RUST_CONFIGURE_ENABLE=		rust
 
 TESTS_CONFIGURE_ENABLE=		unittests
Index: www/cliqz/Makefile
===================================================================
--- www/cliqz/Makefile
+++ www/cliqz/Makefile
@@ -44,7 +44,7 @@
 		png>=1.6.34:graphics/png \
 		${LOCALBASE}/include/pulse/pulseaudio.h:audio/pulseaudio \
 		${PYTHON_PKGNAMEPREFIX}sqlite3>0:databases/py-sqlite3@${PY_FLAVOR} \
-		rust>=1.28:lang/rust \
+		${RUST_DEFAULT}>=1.28:lang/${RUST_DEFAULT} \
 		rust-cbindgen>=0.6.2:devel/rust-cbindgen \
 		sqlite3>=3.24.0:databases/sqlite3 \
 		v4l_compat>0:multimedia/v4l_compat \