diff --git a/src/error.rs b/src/error.rs
index b447a81..a9a52c1 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -183,7 +183,7 @@ impl fmt::Display for Error {
 }
 
 impl failure::Fail for Error {
-    fn cause(&self) -> Option<&failure::Fail> {
+    fn cause(&self) -> Option<&dyn failure::Fail> {
         match *self {
             Error::CallbackError { ref cause, .. } => Some(cause.as_ref()),
             Error::ExternalError(ref err) => err.as_fail().cause(),
diff --git a/src/types.rs b/src/types.rs
index 300467c..90e76fd 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -17,7 +17,7 @@ pub type Number = ffi::lua_Number;
 pub struct LightUserData(pub *mut c_void);
 
 pub(crate) type Callback<'lua, 'a> =
-    Box<Fn(&'lua Lua, MultiValue<'lua>) -> Result<MultiValue<'lua>> + 'a>;
+    Box<dyn Fn(&'lua Lua, MultiValue<'lua>) -> Result<MultiValue<'lua>> + 'a>;
 
 /// An auto generated key into the Lua registry.
 ///
diff --git a/src/util.rs b/src/util.rs
index 544f9d7..57b6441 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -661,11 +661,11 @@ pub unsafe fn init_error_metatables(state: *mut ffi::lua_State) {
 }
 
 struct WrappedError(pub Error);
-struct WrappedPanic(pub Option<Box<Any + Send>>);
+struct WrappedPanic(pub Option<Box<dyn Any + Send>>);
 
 // Pushes a WrappedError::Panic to the top of the stack.  Uses two stack spaces and does not call
 // lua_checkstack.
-unsafe fn push_wrapped_panic(state: *mut ffi::lua_State, panic: Box<Any + Send>) {
+unsafe fn push_wrapped_panic(state: *mut ffi::lua_State, panic: Box<dyn Any + Send>) {
     gc_guard(state, || {
         let ud = ffi::lua_newuserdata(state, mem::size_of::<WrappedPanic>()) as *mut WrappedPanic;
         ptr::write(ud, WrappedPanic(Some(panic)))