diff --git a/argmin/src/core/executor.rs b/argmin/src/core/executor.rs
index 184f9c970..f77ee66fe 100644
--- a/argmin/src/core/executor.rs
+++ b/argmin/src/core/executor.rs
@@ -152,14 +152,15 @@ where
                 let interp = interrupt.clone();
                 // This is currently a hack to allow checkpoints to be run again within the
                 // same program (usually not really a use case anyway). Unfortunately, this
-                // means that any subsequent run started afterwards will have not Ctrl-C
+                // means that any subsequent run started afterwards will not have Ctrl-C
                 // handling available... This should also be a problem in case one tries to run
                 // two consecutive optimizations. There is ongoing work in the ctrlc crate
                 // (channels and such) which may solve this problem. So far, we have to live
                 // with this.
-                match ctrlc::set_handler(move || {
+                let handler = move || {
                     interp.store(true, Ordering::SeqCst);
-                }) {
+                };
+                match ctrlc::set_handler(handler) {
                     Err(ctrlc::Error::MultipleHandlers) => Ok(()),
                     interp => interp,
                 }?;
diff --git a/argmin/src/core/problem.rs b/argmin/src/core/problem.rs
index 763f44e39..9e1048440 100644
--- a/argmin/src/core/problem.rs
+++ b/argmin/src/core/problem.rs
@@ -605,7 +605,7 @@ impl<O: Operator> Problem<O> {
     /// # assert_eq!(res[0], vec![1.0f64, 1.0f64]);
     /// # assert_eq!(res[1], vec![1.0f64, 1.0f64]);
     /// ```
-    pub fn bulk_apply<P>(&mut self, params: &Vec<P>) -> Result<Vec<O::Output>, Error>
+    pub fn bulk_apply<P>(&mut self, params: &[P]) -> Result<Vec<O::Output>, Error>
     where
         P: std::borrow::Borrow<O::Param> + SyncAlias,
         O::Output: SendAlias,
@@ -686,7 +686,7 @@ impl<O: CostFunction> Problem<O> {
     /// # assert_eq!(res[0], 4.0f64);
     /// # assert_eq!(res[1], 4.0f64);
     /// ```
-    pub fn bulk_cost<P>(&mut self, params: &Vec<P>) -> Result<Vec<O::Output>, Error>
+    pub fn bulk_cost<P>(&mut self, params: &[P]) -> Result<Vec<O::Output>, Error>
     where
         P: std::borrow::Borrow<O::Param> + SyncAlias,
         O::Output: SendAlias,
@@ -767,7 +767,7 @@ impl<O: Gradient> Problem<O> {
     /// # assert_eq!(res[0], vec![1.0f64, 1.0f64]);
     /// # assert_eq!(res[1], vec![1.0f64, 1.0f64]);
     /// ```
-    pub fn bulk_gradient<P>(&mut self, params: &Vec<P>) -> Result<Vec<O::Gradient>, Error>
+    pub fn bulk_gradient<P>(&mut self, params: &[P]) -> Result<Vec<O::Gradient>, Error>
     where
         P: std::borrow::Borrow<O::Param> + SyncAlias,
         O::Gradient: SendAlias,
@@ -847,7 +847,7 @@ impl<O: Hessian> Problem<O> {
     /// # assert_eq!(res[0], vec![vec![1.0f64, 0.0f64], vec![0.0f64, 1.0f64]]);
     /// # assert_eq!(res[1], vec![vec![1.0f64, 0.0f64], vec![0.0f64, 1.0f64]]);
     /// ```
-    pub fn bulk_hessian<P>(&mut self, params: &Vec<P>) -> Result<Vec<O::Hessian>, Error>
+    pub fn bulk_hessian<P>(&mut self, params: &[P]) -> Result<Vec<O::Hessian>, Error>
     where
         P: std::borrow::Borrow<O::Param> + SyncAlias,
         O::Hessian: SendAlias,
@@ -926,7 +926,7 @@ impl<O: Jacobian> Problem<O> {
     /// # assert_eq!(res[0], vec![vec![1.0f64, 0.0f64], vec![0.0f64, 1.0f64]]);
     /// # assert_eq!(res[1], vec![vec![1.0f64, 0.0f64], vec![0.0f64, 1.0f64]]);
     /// ```
-    pub fn bulk_jacobian<P>(&mut self, params: &Vec<P>) -> Result<Vec<O::Jacobian>, Error>
+    pub fn bulk_jacobian<P>(&mut self, params: &[P]) -> Result<Vec<O::Jacobian>, Error>
     where
         P: std::borrow::Borrow<O::Param> + SyncAlias,
         O::Jacobian: SendAlias,