diff -r 402d717bb5c0 -r dab30b331f49 src/convex.rs
--- a/src/convex.rs	Mon Sep 01 20:55:34 2025 -0500
+++ b/src/convex.rs	Mon Sep 01 23:03:27 2025 -0500
@@ -4,7 +4,7 @@
 
 use crate::error::DynResult;
 use crate::euclidean::Euclidean;
-use crate::instance::{ClosedSpace, DecompositionMut, Instance};
+use crate::instance::{DecompositionMut, Instance};
 use crate::linops::{IdOp, Scaled, SimpleZeroOp, AXPY};
 use crate::mapping::{DifferentiableImpl, LipschitzDifferentiableImpl, Mapping, Space};
 use crate::norms::*;
@@ -202,7 +202,6 @@
 impl<F, E, Domain> Mapping<Domain> for NormProjection<F, E>
 where
     Domain: Normed<F> + Projection<F, E>,
-    Domain::OwnedSpace: ClosedSpace,
     F: Float,
     E: NormExponent,
 {
@@ -412,10 +411,10 @@
     F: Float,
     X: Euclidean<F>,
 {
-    type Derivative = X::Owned;
+    type Derivative = X::OwnedEuclidean;
 
     fn differential_impl<I: Instance<X>>(&self, x: I) -> Self::Derivative {
-        x.own().into_owned()
+        x.into_owned()
     }
 }