diff --git a/kernmantle/src/Control/Kernmantle/Rope.hs b/kernmantle/src/Control/Kernmantle/Rope.hs
index adf1572..04daa1e 100644
--- a/kernmantle/src/Control/Kernmantle/Rope.hs
+++ b/kernmantle/src/Control/Kernmantle/Rope.hs
@@ -110,7 +110,7 @@ newtype Rope (record::RopeRec) (mantle::[Strand]) (core::BinEff) a b =
            , ThrowEffect ex, TryEffect ex
            , SieveTrans f
            , HasAutoIdent eff
-           , Bifunctor, Biapplicative
+           , Functor, Bifunctor, Biapplicative
            )
 
 runRope :: Rope record mantle core a b -> record (Weaver core) mantle -> core a b
@@ -199,7 +199,7 @@ tighten r = mkRope $ runRope r . fromARec
 
 -- | Turn a 'TightRope' into a 'LooseRope'. This is very often the first step
 -- in a chain of 'weave's.
-loosen :: (NatToInt (RLength m))
+loosen :: (ToARec m, NatToInt (RLength m))
        => TightRope m core :-> LooseRope m core
 loosen r = mkRope $ runRope r . toARec
 {-# INLINE loosen #-}
diff --git a/kernmantle/src/Control/Kernmantle/Rope/Internal.hs b/kernmantle/src/Control/Kernmantle/Rope/Internal.hs
index 72587e1..990b407 100644
--- a/kernmantle/src/Control/Kernmantle/Rope/Internal.hs
+++ b/kernmantle/src/Control/Kernmantle/Rope/Internal.hs
@@ -19,6 +19,7 @@ import Data.Bifunctor
 import Data.Biapplicative
 import Data.Bifunctor.Tannen
 import Data.Functor.Identity
+import Data.Kind (Type)
 import Data.Profunctor.Cayley
 import Data.Profunctor.EffFunctor
 import Data.Profunctor.Monad
@@ -36,10 +37,10 @@ import Control.Kernmantle.Error
 
 -- | The kind for all binary effects. First param is usually an input
 -- (contravariant) of the effect and second one an output (covariant).
-type BinEff = * -> * -> *
+type BinEff = Type -> Type -> Type
 
 -- | The kind for unary effects
-type UnaryEff = * -> *
+type UnaryEff = Type -> Type
 
 -- | The kind for a named binary effect. Must remain a tuple because that's what
 -- vinyl expects.
@@ -53,9 +54,9 @@ type family StrandEff t where
 
 -- | The kind for records that will contain 'Weaver's. First type param will
 -- most often be @Weaver someCore@
-type RopeRec = (Strand -> *) -> [Strand] -> *
+type RopeRec = (Strand -> Type) -> [Strand] -> Type
 
--- | Runs one @strand@ (* -> * -> * effect) in a @interp@ effect. Is
+-- | Runs one @strand@ (Type -> Type -> Type effect) in a @interp@ effect. Is
 -- parameterized over a Strand (and not just a BinEffect) even if it ignores its
 -- name internally because that's what is expect by the 'RopeRec'
 newtype Weaver (interp::BinEff) (strand::Strand) = Weaver
@@ -90,6 +91,9 @@ newtype RopeRunner (record::RopeRec) (mantle::[Strand]) (interp::BinEff) (core::
   deriving (EffFunctor, EffPointedFunctor)
     via Tannen ((->) (record (Weaver interp) mantle))
 
+instance Functor (core a) => Functor (RopeRunner record mantle interp core a) where
+    fmap f (RopeRunner run) = RopeRunner $ \record -> fmap f (run record)
+
 instance (RMap m) => EffProfunctor (RopeRunner Rec m) where
   effdimap f g (RopeRunner run) = RopeRunner $
     g . run . rmap (mapWeaverInterp f)