diff --git a/Cargo.toml b/Cargo.toml
index a856c4e..cb3fb29 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,7 +11,7 @@ name = "parabole"
 path = "examples/parabole.rs"
 
 [dev-dependencies]
-rand = "0.3"
+rand = "0.4"
 criterion = "0.2"
 
 [[bench]]
diff --git a/benches/parabole.rs b/benches/parabole.rs
index 7f67e8f..93e2ac2 100644
--- a/benches/parabole.rs
+++ b/benches/parabole.rs
@@ -50,9 +50,9 @@ impl Individual for Parabole {
     }
 
     fn mutate(&mut self) {
-        let between = Range::new(-1.0, 1.0);
+        let mut rng = rand::weak_rng();
 
-        let mut rng = rand::thread_rng();
+        let between = Range::new(-1.0, 1.0);
         let offset = between.ind_sample(&mut rng);
 
         self.x += offset;
@@ -104,7 +104,7 @@ fn criterion_benchmark(c: &mut Criterion) {
                     )
                     .map(|(a, b)| a.individual.mate(&b.individual))
                     .map(|individual| Wrapper {
-                        individual: individual,
+                        individual,
                         fitness: None,
                     })
                     .for_each(|wrapper| {
@@ -119,7 +119,7 @@ fn criterion_benchmark(c: &mut Criterion) {
                         individual.mutate();
 
                         Wrapper {
-                            individual: individual,
+                            individual,
                             fitness: None,
                         }
                     })
diff --git a/examples/parabole.rs b/examples/parabole.rs
index 32950ab..cd5b76c 100644
--- a/examples/parabole.rs
+++ b/examples/parabole.rs
@@ -7,7 +7,7 @@ use std::cmp::Ordering;
 use rand::distributions::{IndependentSample, Range};
 use rayon::prelude::*;
 
-use genetisk::{Individual, MaximizeSelector, MinimizeSelector, Select, Simulation, Wrapper};
+use genetisk::{Individual, Simulation, Wrapper};
 
 #[derive(Clone, Copy, Debug)]
 struct Fitness(f64);
@@ -47,9 +47,9 @@ impl Individual for Parabole {
     }
 
     fn mutate(&mut self) {
-        let between = Range::new(-1.0, 1.0);
+        let mut rng = rand::weak_rng();
 
-        let mut rng = rand::thread_rng();
+        let between = Range::new(-1.0, 1.0);
         let offset = between.ind_sample(&mut rng);
 
         self.x += offset;
@@ -90,7 +90,7 @@ fn main() {
                 )
                 .map(|(a, b)| a.individual.mate(&b.individual))
                 .map(|individual| Wrapper {
-                    individual: individual,
+                    individual,
                     fitness: None,
                 })
                 .for_each(|wrapper| {
@@ -105,7 +105,7 @@ fn main() {
                     individual.mutate();
 
                     Wrapper {
-                        individual: individual,
+                        individual,
                         fitness: None,
                     }
                 })