diff --git a/benches/arrays.rs b/benches/arrays.rs
index 74c30ed3..06e36577 100644
--- a/benches/arrays.rs
+++ b/benches/arrays.rs
@@ -109,6 +109,15 @@ config = Criterion::default().with_profiler(PProfProfiler::new(100, Output::Flam
         name = "sort normal",
         path = "arrays/sort",
         args = (20),
+    }, {
+        name = "sum normal 50",
+        path = "arrays/sum",
+        args = (50),
+    }, {
+        name = "sum deepseq 50",
+        path = "arrays/sum",
+        args = (50),
+        eval_mode = EvalMode::DeepSeq,
     }
 }
 criterion_main!(benches);
diff --git a/benches/arrays/primes.ncl b/benches/arrays/primes.ncl
new file mode 100644
index 00000000..dd932b77
--- /dev/null
+++ b/benches/arrays/primes.ncl
@@ -0,0 +1,37 @@
+let range
+  | doc "Generate an array of integers in the range [`start`, `end`)."
+  | Num -> Num -> Array Num
+  = fun start end =>
+    if end <= start then 
+      []
+    else
+      array.generate (fun x => x + start) (end - start) 
+in
+
+let is_prime 
+  | doc "Returns true if the argument is a prime number."
+  = fun x => x > 1 && array.all (fun d => x % d != 0) (range 2 (x - 1))
+in
+
+let Prime = contract.from_predicate is_prime in
+
+let primes 
+  | doc "Generate `max` primes using Sieve of Eratosthenes."
+  | Num -> Array Prime
+  = fun max =>
+    let limit = num.pow max (1 / 2) in # sqrt(max)
+    let drop_multiples = fun x xs => 
+      let to_drop = max
+        |> array.generate (fun y => (y + 2) * x)
+        |> array.filter (fun y => y <= max) in
+      array.filter (fun y => array.all ((!=) y) to_drop) xs in
+    let rec loop = fun x xs =>
+      if x > limit then
+        xs
+      else
+        loop (x + 1) (drop_multiples x xs) in
+    loop 2 (range 2 max) in
+
+{
+  run = primes
+}
diff --git a/benches/arrays/sum.ncl b/benches/arrays/sum.ncl
new file mode 100644
index 00000000..d5cc1ff2
--- /dev/null
+++ b/benches/arrays/sum.ncl
@@ -0,0 +1,8 @@
+let sum
+  | Array Num -> Num 
+  = fun xs =>
+    if array.length xs == 0 then 0
+    else array.head xs + sum (array.tail xs)
+in {
+  run = fun n => array.generate (fun x => x + 1) n |> sum
+}