diff --git a/Cargo.toml b/Cargo.toml
index 546db24..9258d71 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,7 +2,7 @@
 name = "graphene"
 version = "0.1.5"
 authors = ["Emad Jacob Maroun <emoun.open@gmail.com>"]
-edition = "2018"
+edition = "2021"
 
 description = "A general purpose, extensible Graph Theory data type and algorithm library for Rust."
 
@@ -19,7 +19,7 @@ categories = ["data-structures","algorithms"]
 travis-ci = {repository = "Emoun/graphene"}
 
 [dependencies]
-delegate = "0.4.2"
+delegate = "0.13.1"
 tt-equal = "0.1"
 tt-call = "1.0"
 num-traits = "0.2"
@@ -29,4 +29,4 @@ rand = "0.7"
 quickcheck = "0.9"
 quickcheck_macros = "0.9"
 static_assertions = "1.1.0"
-duplicate = "0.2.9"
\ No newline at end of file
+duplicate = "2.0.0"
diff --git a/rustfmt.toml b/rustfmt.toml
index cb4cc24..dc2746e 100644
--- a/rustfmt.toml
+++ b/rustfmt.toml
@@ -6,7 +6,7 @@ empty_item_single_line=true
 force_multiline_blocks=true
 format_strings=true
 hard_tabs=true
-merge_imports=true
+imports_granularity="Crate"
 newline_style="Unix"
 normalize_comments=true
 normalize_doc_attributes=true
diff --git a/src/common/adjacency_list/impl_graph.rs b/src/common/adjacency_list/impl_graph.rs
index bf4fa96..d718f81 100644
--- a/src/common/adjacency_list/impl_graph.rs
+++ b/src/common/adjacency_list/impl_graph.rs
@@ -16,9 +16,9 @@ where
 	type Vertex = usize;
 	type VertexWeight = Vw;
 
-	fn all_vertices_weighted<'a>(
-		&'a self,
-	) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>
+	fn all_vertices_weighted(
+		&self,
+	) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>
 	{
 		Box::new(self.vertices.iter().enumerate().map(|(v, (w, _))| (v, w)))
 	}
diff --git a/src/common/adjacency_list/mod.rs b/src/common/adjacency_list/mod.rs
index c4b1dec..59bbb76 100644
--- a/src/common/adjacency_list/mod.rs
+++ b/src/common/adjacency_list/mod.rs
@@ -1,6 +1,5 @@
 mod impl_graph;
 
-pub use self::impl_graph::*;
 use crate::core::{Directed, Directedness};
 use std::marker::PhantomData;
 
diff --git a/src/core/graph.rs b/src/core/graph.rs
index 9163a92..ab74790 100644
--- a/src/core/graph.rs
+++ b/src/core/graph.rs
@@ -75,9 +75,9 @@ pub trait Graph
 	type Directedness: Directedness;
 
 	/// Returns copies of all current vertex values in the graph.
-	fn all_vertices_weighted<'a>(
-		&'a self,
-	) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+	fn all_vertices_weighted(
+		&self,
+	) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 
 	/// Returns the weights of all edges that are sourced in v1 and sinked in
 	/// v2. I.e. all edges where e == (v1,v2,_).
@@ -216,11 +216,12 @@ pub trait Graph
 	{
 		self.edges_between(v1.borrow(), v2.borrow())
 			.next()
-			.is_some() || (Self::Directedness::directed()
-			&& self
-				.edges_between(v2.borrow(), v1.borrow())
-				.next()
-				.is_some())
+			.is_some()
+			|| (Self::Directedness::directed()
+				&& self
+					.edges_between(v2.borrow(), v1.borrow())
+					.next()
+					.is_some())
 	}
 }
 
@@ -232,9 +233,9 @@ pub trait Graph
 /// methods plus some additional utilities.
 pub trait GraphMut: Graph
 {
-	fn all_vertices_weighted_mut<'a>(
-		&'a mut self,
-	) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a mut Self::VertexWeight)>>;
+	fn all_vertices_weighted_mut(
+		&mut self,
+	) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &mut Self::VertexWeight)>>;
 
 	fn edges_between_mut<'a: 'b, 'b>(
 		&'a mut self,
diff --git a/src/core/property/acyclic.rs b/src/core/property/acyclic.rs
index 2aa0952..8aa8cc6 100644
--- a/src/core/property/acyclic.rs
+++ b/src/core/property/acyclic.rs
@@ -8,9 +8,7 @@ use crate::{
 use std::borrow::Borrow;
 
 /// An acyclic graph
-pub trait Acyclic: NoLoops
-{
-}
+pub trait Acyclic: NoLoops {}
 
 #[derive(Clone, Debug)]
 pub struct AcyclicGraph<C: Ensure>(C);
diff --git a/src/core/property/connected.rs b/src/core/property/connected.rs
index 5ac7e1d..4266e86 100644
--- a/src/core/property/connected.rs
+++ b/src/core/property/connected.rs
@@ -15,9 +15,7 @@ use std::borrow::Borrow;
 ///
 /// A graph is connected if there is a path from any vertex to any other vertex.
 /// Graphs with one or zero vertices count as connected.
-pub trait Connected: Unilateral
-{
-}
+pub trait Connected: Unilateral {}
 
 #[derive(Clone, Debug)]
 pub struct ConnectedGraph<C: Ensure>(C);
diff --git a/src/core/property/directedness_ensurers.rs b/src/core/property/directedness_ensurers.rs
index 8558560..3b73d5e 100644
--- a/src/core/property/directedness_ensurers.rs
+++ b/src/core/property/directedness_ensurers.rs
@@ -27,9 +27,9 @@ impl<C: Ensure> Graph for DirectedGraph<C>
 
 	delegate! {
 		to self.0.graph() {
-			fn all_vertices_weighted<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 
 			fn edges_between<'a: 'b, 'b>(
 				&'a self,
@@ -70,9 +70,9 @@ impl<C: Ensure> Graph for UndirectedGraph<C>
 
 	delegate! {
 		to self.0.graph() {
-			fn all_vertices_weighted<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 
 			fn edges_between<'a: 'b, 'b>(
 				&'a self,
diff --git a/src/core/property/impl_ensurer.rs b/src/core/property/impl_ensurer.rs
index 8c47040..575b158 100644
--- a/src/core/property/impl_ensurer.rs
+++ b/src/core/property/impl_ensurer.rs
@@ -244,9 +244,9 @@ macro_rules! impl_properties {
 
 				delegate::delegate! {
 					to $crate::core::GraphDeref::graph(&self$($delegate)+){
-						fn all_vertices_weighted<'a>(
-							&'a self,
-						) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+						fn all_vertices_weighted(
+							&self,
+						) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 
 						fn edges_between<'a: 'b, 'b>(
 							&'a self,
@@ -275,11 +275,9 @@ macro_rules! impl_properties {
 			@implement {
 				delegate::delegate! {
 					to $crate::core::GraphDerefMut::graph_mut(&mut self$($delegate)+) {
-						fn all_vertices_weighted_mut<'a>(
-							&'a mut self,
-						) -> Box<dyn 'a + Iterator<
-							Item = (Self::Vertex, &'a mut Self::VertexWeight)
-						>>;
+						fn all_vertices_weighted_mut(
+							&mut self,
+						) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &mut Self::VertexWeight)>>;
 
 						fn edges_between_mut<'a: 'b, 'b>(
 							&'a mut self,
@@ -511,7 +509,7 @@ macro_rules! impl_properties {
 			@implement {
 				delegate::delegate!{
 					to $crate::core::GraphDeref::graph(&self$($delegate)+) {
-						fn exit_edges<'a>(&'a self) -> Box<dyn 'a + Iterator<Item=
+						fn exit_edges(&self) -> Box<dyn '_ + Iterator<Item=
 							(Self::Vertex, Self::Vertex)>>;
 					}
 				}
diff --git a/src/core/property/mod.rs b/src/core/property/mod.rs
index fa50723..dcc1f0b 100644
--- a/src/core/property/mod.rs
+++ b/src/core/property/mod.rs
@@ -14,9 +14,8 @@ mod unique;
 mod weak;
 
 pub use self::{
-	acyclic::*, base_props::*, connected::*, directedness_ensurers::*, has_vertex::*,
-	impl_ensurer::*, no_loops::*, reflexive::*, rooted::*, subgraph::*, unilateral::*, unique::*,
-	weak::*,
+	acyclic::*, base_props::*, connected::*, directedness_ensurers::*, has_vertex::*, no_loops::*,
+	reflexive::*, rooted::*, subgraph::*, unilateral::*, unique::*, weak::*,
 };
 use crate::core::{
 	proxy::{EdgeProxyGraph, ProxyVertex, VertexProxyGraph},
diff --git a/src/core/property/no_loops.rs b/src/core/property/no_loops.rs
index fb73529..6a93965 100644
--- a/src/core/property/no_loops.rs
+++ b/src/core/property/no_loops.rs
@@ -6,9 +6,7 @@ use std::borrow::Borrow;
 /// In graph theory, a loop is an edge that connects a vertex to itself.
 /// This trait guarantees that there are no loops in the graph and that no loops
 /// can be added to it.
-pub trait NoLoops: Graph
-{
-}
+pub trait NoLoops: Graph {}
 
 pub struct NoLoopsGraph<C: Ensure>(C);
 
diff --git a/src/core/property/subgraph.rs b/src/core/property/subgraph.rs
index ab093bc..0eaa8a1 100644
--- a/src/core/property/subgraph.rs
+++ b/src/core/property/subgraph.rs
@@ -3,7 +3,7 @@ use crate::core::{Edge, Graph};
 pub trait Subgraph: Graph
 {
 	/// Edges who's sources are in this subgraph but who's sinks aren't.
-	fn exit_edges<'a>(&'a self) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, Self::Vertex)>>;
+	fn exit_edges(&self) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, Self::Vertex)>>;
 
 	/// Whether this subgraph can reach a vertex in the other subgraph, either
 	/// by sharing a vertex with it, or having an axit edge to one of its
diff --git a/src/core/property/unilateral.rs b/src/core/property/unilateral.rs
index 2a4f19c..bba2270 100644
--- a/src/core/property/unilateral.rs
+++ b/src/core/property/unilateral.rs
@@ -23,9 +23,7 @@ use std::borrow::Borrow;
 /// For undirected graph, simply use `ConnectedGraph`.
 ///
 /// For type safety reasons, the trait itself does not restrict directedness.
-pub trait Unilateral: Weak
-{
-}
+pub trait Unilateral: Weak {}
 
 #[derive(Clone, Debug)]
 pub struct UnilateralGraph<C: Ensure>(C)
diff --git a/src/core/property/weak.rs b/src/core/property/weak.rs
index 5c9889e..a60af23 100644
--- a/src/core/property/weak.rs
+++ b/src/core/property/weak.rs
@@ -19,9 +19,7 @@ use std::borrow::Borrow;
 /// undirected graph, simply use `ConnectedGraph`.
 ///
 /// For type safety reasons, the trait itself does not restrict directedness.
-pub trait Weak: Graph
-{
-}
+pub trait Weak: Graph {}
 
 #[derive(Clone, Debug)]
 pub struct WeakGraph<C: Ensure>(C)
diff --git a/src/core/proxy/edge_proxy.rs b/src/core/proxy/edge_proxy.rs
index 97893d3..d7a459f 100644
--- a/src/core/proxy/edge_proxy.rs
+++ b/src/core/proxy/edge_proxy.rs
@@ -3,7 +3,7 @@ use crate::core::{
 	Directedness, Edge, Ensure, Graph, GraphDerefMut, GraphMut,
 };
 use delegate::delegate;
-use std::borrow::Borrow;
+use std::{borrow::Borrow, cell::UnsafeCell};
 
 /// A wrapper around a graph, that allows for addition and removal
 /// of edges, without mutating the underlying graph.
@@ -55,9 +55,9 @@ impl<C: Ensure> Graph for EdgeProxyGraph<C>
 
 	delegate! {
 		to self.graph.graph() {
-			fn all_vertices_weighted<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 		}
 	}
 
@@ -94,9 +94,9 @@ where
 {
 	delegate! {
 		to self.graph.graph_mut() {
-			fn all_vertices_weighted_mut<'a>(
-				&'a mut self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a mut Self::VertexWeight)>>;
+			fn all_vertices_weighted_mut(
+				&mut self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &mut Self::VertexWeight)>>;
 		}
 	}
 
@@ -109,7 +109,7 @@ where
 		// Safe because &mut () can't mutate anything
 		Box::new(
 			self.edges_between(source, sink)
-				.map(|w| unsafe { &mut *((w as *const ()) as *mut ()) }),
+				.map(|_| unsafe { &mut *UnsafeCell::new(()).get() }),
 		)
 	}
 }
diff --git a/src/core/proxy/reverse_graph.rs b/src/core/proxy/reverse_graph.rs
index b4f51d6..9223a9f 100644
--- a/src/core/proxy/reverse_graph.rs
+++ b/src/core/proxy/reverse_graph.rs
@@ -32,8 +32,8 @@ where
 
 	delegate! {
 		to self.0.graph() {
-			fn all_vertices_weighted<'a>(&'a self) -> Box<dyn 'a + Iterator<Item=
-				(Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(&self) -> Box<dyn '_ + Iterator<Item=
+				(Self::Vertex, &Self::VertexWeight)>>;
 		}
 	}
 
@@ -53,8 +53,8 @@ where
 {
 	delegate! {
 		to self.0.graph_mut() {
-			fn all_vertices_weighted_mut<'a>(&'a mut self) -> Box<dyn 'a + Iterator<Item=
-				(Self::Vertex, &'a mut Self::VertexWeight)>>;
+			fn all_vertices_weighted_mut(&mut self) -> Box<dyn '_ + Iterator<Item=
+				(Self::Vertex, &mut Self::VertexWeight)>>;
 		}
 	}
 
diff --git a/src/core/proxy/subgraph_proxy.rs b/src/core/proxy/subgraph_proxy.rs
index 159f2e0..9af9244 100644
--- a/src/core/proxy/subgraph_proxy.rs
+++ b/src/core/proxy/subgraph_proxy.rs
@@ -69,9 +69,9 @@ impl<C: Ensure> Graph for SubgraphProxy<C>
 	type Vertex = <C::Graph as Graph>::Vertex;
 	type VertexWeight = <C::Graph as Graph>::VertexWeight;
 
-	fn all_vertices_weighted<'a>(
-		&'a self,
-	) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>
+	fn all_vertices_weighted(
+		&self,
+	) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>
 	{
 		Box::new(
 			self.graph
diff --git a/src/core/proxy/undirected_proxy.rs b/src/core/proxy/undirected_proxy.rs
index 11f4fc9..2351887 100644
--- a/src/core/proxy/undirected_proxy.rs
+++ b/src/core/proxy/undirected_proxy.rs
@@ -31,9 +31,9 @@ where
 
 	delegate! {
 		to self.0.graph() {
-			fn all_vertices_weighted<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 		}
 	}
 
diff --git a/src/core/proxy/vertex_proxy.rs b/src/core/proxy/vertex_proxy.rs
index 1ae7b45..a4c2196 100644
--- a/src/core/proxy/vertex_proxy.rs
+++ b/src/core/proxy/vertex_proxy.rs
@@ -50,9 +50,9 @@ impl<C: Ensure> Graph for VertexProxyGraph<C>
 	type Vertex = ProxyVertex<<C::Graph as Graph>::Vertex>;
 	type VertexWeight = ();
 
-	fn all_vertices_weighted<'a>(
-		&'a self,
-	) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>
+	fn all_vertices_weighted(
+		&self,
+	) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>
 	{
 		Box::new(
 			self.graph
diff --git a/tests/algo/bfs.rs b/tests/algo/bfs.rs
index bc7acb9..265dbe1 100644
--- a/tests/algo/bfs.rs
+++ b/tests/algo/bfs.rs
@@ -1,5 +1,5 @@
 use crate::mock_graph::{arbitrary::Arb, MockGraph};
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::{
 	algo::Bfs,
 	core::{
@@ -9,7 +9,7 @@ use graphene::{
 };
 use std::collections::HashSet;
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [ Directed ]; [ Undirected ]
 )]
 mod __
diff --git a/tests/algo/dfs.rs b/tests/algo/dfs.rs
index 892981d..8be2d0e 100644
--- a/tests/algo/dfs.rs
+++ b/tests/algo/dfs.rs
@@ -1,7 +1,7 @@
 //! Tests `Dfs`
 
 use crate::mock_graph::{arbitrary::Arb, MockGraph, MockVertex};
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::{
 	algo::Dfs,
 	core::{
@@ -11,7 +11,7 @@ use graphene::{
 };
 use std::cell::Cell;
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [ Directed ]; [ Undirected ]
 )]
 mod __
diff --git a/tests/algo/dijkstra_shortest_paths.rs b/tests/algo/dijkstra_shortest_paths.rs
index c6f770f..24a5bbb 100644
--- a/tests/algo/dijkstra_shortest_paths.rs
+++ b/tests/algo/dijkstra_shortest_paths.rs
@@ -1,7 +1,7 @@
 use crate::mock_graph::arbitrary::{Arb, VerticesIn};
 /// tests `DijkstraShortestPath`
 use crate::mock_graph::{MockEdgeWeight, MockGraph};
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::{
 	algo::DijkstraShortestPaths,
 	core::{
@@ -11,7 +11,7 @@ use graphene::{
 };
 use std::collections::{HashMap, HashSet};
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [ Directed ]; [ Undirected ]
 )]
 mod __
diff --git a/tests/algo/search.rs b/tests/algo/search.rs
index 7fc1a96..f4e7eb0 100644
--- a/tests/algo/search.rs
+++ b/tests/algo/search.rs
@@ -1,7 +1,7 @@
 use crate::mock_graph::arbitrary::Arb;
 /// Common tests for all 'searching' algorithms.
 use crate::mock_graph::{MockEdgeWeight, MockGraph};
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::{
 	algo::{Bfs, Dfs, Spfs},
 	core::{
@@ -19,7 +19,7 @@ fn spfs_new<G: HasVertex<EdgeWeight = MockEdgeWeight>>(g: &G) -> Spfs<G, u32>
 	Spfs::new(g, |v| v.value)
 }
 
-#[duplicate(
+#[duplicate_item(
 	module		search_algo_new;
 	[ dfs ]		[ Dfs::new_simple ];
 	[ bfs ]		[ Bfs::new ];
@@ -30,7 +30,7 @@ mod module
 	use super::*;
 	use crate::mock_graph::arbitrary::VerticesIn;
 
-	#[duplicate(
+	#[duplicate_item(
 		directedness; [ Directed ]; [ Undirected ]
 	)]
 	mod __
diff --git a/tests/common/adjacency_list/impl_graph.rs b/tests/common/adjacency_list/impl_graph.rs
index 338a66d..6c61fde 100644
--- a/tests/common/adjacency_list/impl_graph.rs
+++ b/tests/common/adjacency_list/impl_graph.rs
@@ -8,13 +8,13 @@ use crate::{
 		MockGraph,
 	},
 };
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::core::{
 	property::{EdgeCount, HasVertex, RemoveEdge, RemoveVertex, VertexCount, VertexInGraph},
 	Directed, Graph, GraphMut, ReleaseUnloaded, Undirected,
 };
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [Directed]; [Undirected];
 )]
 mod __
diff --git a/tests/common/ensured.rs b/tests/common/ensured.rs
index 15ae70b..23d60fe 100644
--- a/tests/common/ensured.rs
+++ b/tests/common/ensured.rs
@@ -2,7 +2,7 @@
 //! the new versions of each method give the same result
 //! as the original.
 use crate::mock_graph::{arbitrary::Arb, MockGraph, MockVertex, MockVertexWeight};
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::{
 	common::Ensured,
 	core::{
@@ -17,7 +17,7 @@ use graphene::{
 /// for both calls. This will ensure even through one of them is
 /// renamed (using a tool to find and rename usages automatically), this
 /// will fail to compile if the other isn't renamed too.
-#[duplicate(
+#[duplicate_item(
 	contains_vertex; [contains_vertex]
 )]
 #[quickcheck]
@@ -35,7 +35,7 @@ fn contains_vertex(Arb(graph): Arb<MockGraph<Directed>>, v: MockVertex) -> bool
 
 /// Tests that `new_vertex` and `new_vertex_weighted` for EnsureGraph are
 /// identical to their originals.
-#[duplicate(
+#[duplicate_item(
 	new_vertex				arguments;
 	[new_vertex_weighted]	[_w.clone()];
 	[new_vertex]			[]
diff --git a/tests/core/ensure.rs b/tests/core/ensure.rs
index 580a043..0f7c7f7 100644
--- a/tests/core/ensure.rs
+++ b/tests/core/ensure.rs
@@ -70,13 +70,13 @@ impl<C: Ensure> Graph for MockEnsurer<C>
 
 	delegate! {
 		to self.0.graph() {
-			fn all_vertices_weighted<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 
-			fn all_edges<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, Self::Vertex, &'a Self::EdgeWeight)>>;
+			fn all_edges(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, Self::Vertex, &Self::EdgeWeight)>>;
 
 			fn edges_between<'a: 'b, 'b>(
 				&'a self,
@@ -92,9 +92,9 @@ where
 {
 	delegate! {
 		to self.0.graph_mut() {
-			fn all_vertices_weighted_mut<'a>(
-				&'a mut self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a mut Self::VertexWeight)>>;
+			fn all_vertices_weighted_mut(
+				&mut self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &mut Self::VertexWeight)>>;
 
 			fn edges_between_mut<'a: 'b, 'b>(
 				&'a mut self,
@@ -171,13 +171,13 @@ impl<C: Ensure> Graph for MockUnloadedEnsurer<C>
 
 	delegate! {
 		to self.0.graph() {
-			fn all_vertices_weighted<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, &'a Self::VertexWeight)>>;
+			fn all_vertices_weighted(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, &Self::VertexWeight)>>;
 
-			fn all_edges<'a>(
-				&'a self,
-			) -> Box<dyn 'a + Iterator<Item = (Self::Vertex, Self::Vertex, &'a Self::EdgeWeight)>>;
+			fn all_edges(
+				&self,
+			) -> Box<dyn '_ + Iterator<Item = (Self::Vertex, Self::Vertex, &Self::EdgeWeight)>>;
 
 			fn edges_between<'a: 'b, 'b>(
 				&'a self,
diff --git a/tests/core/graph/edge_lookup_methods.rs b/tests/core/graph/edge_lookup_methods.rs
index f899589..4dea7a5 100644
--- a/tests/core/graph/edge_lookup_methods.rs
+++ b/tests/core/graph/edge_lookup_methods.rs
@@ -4,7 +4,7 @@ use crate::mock_graph::{
 	utilities::*,
 	MockGraph,
 };
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::core::{
 	property::{HasVertex, VertexInGraph},
 	Directed, Edge, Graph, ReleaseUnloaded, Undirected,
@@ -12,22 +12,24 @@ use graphene::core::{
 
 use crate::mock_graph::arbitrary::{Arb, TwoVerticesIn};
 
-#[duplicate(
-	#[
-		module_nested				method_nested		closure_nested		directedness_nested;
-		[edges_sourced_in_directed]	[edges_sourced_in]	[e.source() == v]	[ Directed ];
-		[edges_sinked_in_directed]	[edges_sinked_in]	[e.sink() == v]		[ Directed ];
-		[edges_incident_directed]	[edges_incident_on]	[e.source() == v
-															|| e.sink() == v]	[ Directed ];
-		#[
-			module							method;
-			[edges_sourced_in_undirected]	[edges_sourced_in];
-			[edges_sinked_in_undirected]	[edges_sinked_in];
-			[edges_incident_undirected]		[edges_incident_on];
-		][
-			[module]	[method]	[e.source() == v || e.sink() == v]	[ Undirected ];
+#[duplicate_item(
+	duplicate!{
+		[
+			module_nested				method_nested		closure_nested		directedness_nested;
+			[edges_sourced_in_directed]	[edges_sourced_in]	[e.source() == v]	[ Directed ];
+			[edges_sinked_in_directed]	[edges_sinked_in]	[e.sink() == v]		[ Directed ];
+			[edges_incident_directed]	[edges_incident_on]	[e.source() == v
+																|| e.sink() == v]	[ Directed ];
+			duplicate!{
+				[
+					module							method;
+					[edges_sourced_in_undirected]	[edges_sourced_in];
+					[edges_sinked_in_undirected]	[edges_sinked_in];
+					[edges_incident_undirected]		[edges_incident_on];
+				]
+				[module]	[method]	[e.source() == v || e.sink() == v]	[ Undirected ];
+			}
 		]
-	][
 		[
 			module					[ module_nested ]
 			method 					[ method_nested ]
@@ -39,12 +41,13 @@ use crate::mock_graph::arbitrary::{Arb, TwoVerticesIn};
 			arb_invalid_graph 		[ VertexOutside ]
 			base_graph 				[ MockGraph<directedness_nested> ]
 		]
-	]
-	#[
-		module_nested				directedness 	closure_additional;
-		[edges_between_directed] 	[Directed]		[ false ];
-		[edges_between_undirected] 	[Undirected]	[ (e.source() == _v2 && e.sink() == v) ];
-	][
+	}
+	duplicate!{
+		[
+			module_nested				directedness 	closure_additional;
+			[edges_between_directed] 	[Directed]		[ false ];
+			[edges_between_undirected] 	[Undirected]	[ (e.source() == _v2 && e.sink() == v) ];
+		]
 		[
 			module					[module_nested]
 			method 					[edges_between]
@@ -64,7 +67,7 @@ use crate::mock_graph::arbitrary::{Arb, TwoVerticesIn};
 			arb_invalid_graph 		[ EdgeOutside ]
 			base_graph 				[ MockGraph<directedness> ]
 		]
-	]
+	}
 )]
 mod module
 {
diff --git a/tests/core/property/acyclic.rs b/tests/core/property/acyclic.rs
index 393d486..3d4e597 100644
--- a/tests/core/property/acyclic.rs
+++ b/tests/core/property/acyclic.rs
@@ -4,14 +4,14 @@ use crate::mock_graph::{
 	arbitrary::{Arb, EdgeIn, TwoReachableVerticesIn},
 	MockEdgeWeight, MockGraph,
 };
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::core::{
 	property::{Acyclic, AcyclicGraph, AddEdge, HasVertex, NoLoops, RemoveEdge},
 	Directed, EnsureUnloaded, Graph, ReleaseUnloaded, Undirected,
 };
 use static_assertions::assert_impl_all;
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [ Directed ]; [ Undirected ]
 )]
 mod __
diff --git a/tests/core/property/connectedness.rs b/tests/core/property/connectedness.rs
index b5263b6..a3d4380 100644
--- a/tests/core/property/connectedness.rs
+++ b/tests/core/property/connectedness.rs
@@ -4,7 +4,7 @@ use crate::mock_graph::{
 	arbitrary::{Arb, TwoVerticesIn, UnconnectedGraph},
 	MockDirectedness, MockEdgeWeight, MockGraph, MockVertexWeight,
 };
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::core::{
 	property::{
 		AddEdge, Connected, ConnectedGraph, HasVertex, NewVertex, RemoveEdge, RemoveVertex,
@@ -14,12 +14,13 @@ use graphene::core::{
 };
 use static_assertions::assert_impl_all;
 
-#[duplicate(
-	#[
-		module_connected		directedness;
-		[connected_directed]	[Directed];
-		[connected_undirected]	[Undirected]
-	][
+#[duplicate_item(
+	duplicate!{
+		[
+			module_connected		directedness;
+			[connected_directed]	[Directed];
+			[connected_undirected]	[Undirected]
+		]
 		[
 			module				[ module_connected ]
 			connected_graph		[ ConnectedGraph ]
@@ -27,7 +28,7 @@ use static_assertions::assert_impl_all;
 			arb_unconnected		[ UnconnectedGraph<directedness> ]
 			arb_reject_remove	[ ConnectedGraph<MockGraph<directedness>> ]
 		]
-	]
+	}
 	[
 		module				[ unilateral ]
 		connected_graph		[ UnilateralGraph ]
diff --git a/tests/core/property/has_vertex_rooted.rs b/tests/core/property/has_vertex_rooted.rs
index 02283a4..bb45da9 100644
--- a/tests/core/property/has_vertex_rooted.rs
+++ b/tests/core/property/has_vertex_rooted.rs
@@ -4,7 +4,7 @@ use crate::mock_graph::{
 	arbitrary::{Arb, TwoVerticesIn},
 	MockGraph, MockVertexWeight,
 };
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::core::{
 	property::{
 		HasVertex, HasVertexGraph, NewVertex, RemoveVertex, Rooted, RootedGraph, VertexInGraph,
@@ -12,7 +12,7 @@ use graphene::core::{
 	Directed, Undirected,
 };
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [ Directed ]; [ Undirected ]
 )]
 mod __
@@ -65,7 +65,7 @@ mod __
 		}
 	}
 
-	#[duplicate(
+	#[duplicate_item(
 		GraphStruct 		get_method 		set_method;
 		[ VertexInGraph ] 	[ get_vertex ] 	[ set_vertex ];
 		[ RootedGraph ] 	[ root ] 		[ set_root ]
diff --git a/tests/core/property/unique.rs b/tests/core/property/unique.rs
index bdfc607..895f5c9 100644
--- a/tests/core/property/unique.rs
+++ b/tests/core/property/unique.rs
@@ -3,13 +3,13 @@ use crate::mock_graph::{
 	arbitrary::{Arb, EdgeIn, NonUniqueGraph},
 	MockEdgeWeight, MockGraph, MockVertexWeight,
 };
-use duplicate::duplicate;
+use duplicate::duplicate_item;
 use graphene::core::{
 	property::{AddEdge, HasVertex, NewVertex, UniqueGraph, VertexInGraph},
 	Directed, EnsureUnloaded, Graph, ReleaseUnloaded, Undirected,
 };
 
-#[duplicate(
+#[duplicate_item(
 	directedness; [ Directed ]; [ Undirected ]
 )]
 mod __
diff --git a/tests/mock_graph/arbitrary/combinations/edge_outside.rs b/tests/mock_graph/arbitrary/combinations/edge_outside.rs
index bd8022a..43730bb 100644
--- a/tests/mock_graph/arbitrary/combinations/edge_outside.rs
+++ b/tests/mock_graph/arbitrary/combinations/edge_outside.rs
@@ -76,7 +76,8 @@ where
 				.map(|g| Self(g, self.1, self.2)),
 		);
 
-		// 	We then shrink the vertices, ensuring that at least one of them stays invalid
+		// 	We then shrink the vertices, ensuring that at least one of them stays
+		// invalid
 		result.extend(
 			self.1
 				.shrink()
diff --git a/tests/mock_graph/arbitrary/mod.rs b/tests/mock_graph/arbitrary/mod.rs
index ae4207e..70bf663 100644
--- a/tests/mock_graph/arbitrary/mod.rs
+++ b/tests/mock_graph/arbitrary/mod.rs
@@ -7,6 +7,5 @@ mod unique_graph;
 mod vertex_in_graph;
 
 pub use self::{
-	acyclic_graph::*, combinations::*, connected_graph::*, guided_arb_graph::*, mock_graph::*,
-	unique_graph::*, vertex_in_graph::*,
+	acyclic_graph::*, combinations::*, connected_graph::*, guided_arb_graph::*, unique_graph::*,
 };