diff --git a/.ocamlformat b/.ocamlformat
index 8a3b53e..9ed4c26 100644
--- a/.ocamlformat
+++ b/.ocamlformat
@@ -1 +1 @@
-version = 0.26.2
+version = 0.27.0
diff --git a/bin/day2401.ml b/bin/day2401.ml
index 7a6e0b0..148a926 100644
--- a/bin/day2401.ml
+++ b/bin/day2401.ml
@@ -1,12 +1,12 @@
-(** [pair_nums_from_string s] takes a string of two numbers separated by 
+(** [pair_nums_from_string s] takes a string of two numbers separated by
     whitespace and returns the pair of the numbers *)
 let pair_ints_of_string s =
-  match Aoc.ints_of_string s with
+  match Aoc.ints_of_string ~sep:" " s with
   | [ h; h' ] -> (h, h')
   | _ -> raise (Invalid_argument "pair_nums_from_string")
 
-(** [rev_split lst] takes a list of pairs and returns a pair of lists.  Is 
-    equivalent to List.split (List.rev lst) but more efficient (and tail 
+(** [rev_split lst] takes a list of pairs and returns a pair of lists. Is
+    equivalent to List.split (List.rev lst) but more efficient (and tail
     recursive). *)
 let rev_split lst =
   let rec impl acc acc' = function
@@ -16,7 +16,7 @@ let rev_split lst =
   impl [] [] lst
 
 (** [count lst n] counts the number of times [n] appears as an element in [lst].
-    *)
+*)
 let count lst n =
   List.fold_left (fun acc x -> if x = n then acc + 1 else acc) 0 lst
 
diff --git a/bin/day2405.ml b/bin/day2405.ml
index 103d8ef..d406a0f 100644
--- a/bin/day2405.ml
+++ b/bin/day2405.ml
@@ -14,7 +14,7 @@ let find_rule a b m =
   | Some s -> ( match IntSet.find_opt b s with Some _ -> true | None -> false)
   | None -> false
 
-(** [compare m a b] is a total ordering on pages in the rule map [m].  Returns
+(** [compare m a b] is a total ordering on pages in the rule map [m]. Returns
     [-1] if [a] should appear before [b], [0] if [a = b], and [1] if [b] should
     appear before [a]. *)
 let compare m a b =
@@ -35,9 +35,9 @@ let rec is_page_order_valid m pages =
   in
   match pages with h :: t -> impl h t && is_page_order_valid m t | [] -> true
 
-(** [parse_rules lst] parses the rules in the list [lst] stopping when 
-    encountering an empty line.  Returns a pair [(rule_map, tail)]. 
-    [tail] starts the line after the empty line. *)
+(** [parse_rules lst] parses the rules in the list [lst] stopping when
+    encountering an empty line. Returns a pair [(rule_map, tail)]. [tail] starts
+    the line after the empty line. *)
 let parse_rules =
   let m = Hashtbl.create 17 in
   let rec impl = function
@@ -52,7 +52,7 @@ let parse_rules =
   in
   impl
 
-(** [parse_page_orders lst] parses a list of page orders.  *)
+(** [parse_page_orders lst] parses a list of page orders. *)
 let parse_page_orders =
   let rec impl acc = function
     | [] -> acc
diff --git a/lib/aoc.mli b/lib/aoc.mli
index 473de53..3acc871 100644
--- a/lib/aoc.mli
+++ b/lib/aoc.mli
@@ -1,18 +1,17 @@
 val ints_of_string : ?sep:string -> string -> int list
 (** [nums_from_string ?sep s] takes a string of integers separated by [sep] and
-    gives back a list of the integers.  By default [sep] is " " *)
+    gives back a list of the integers. By default [sep] is " " *)
 
 val distance1 : int -> int -> int
 (** [distance1 a b] returns the absolute difference between [a] and [b]. *)
 
 val strings_of_file : string -> string list
-(** [strings_from_file fname] returns a list of strings from the file 
-    [fname].  Each string represents a line from the file. *)
+(** [strings_from_file fname] returns a list of strings from the file [fname].
+    Each string represents a line from the file. *)
 
 val main : (string -> 'a) -> (('b -> string) * ('a -> 'b)) list -> unit
-(** [main prep parts] executes an advent of code problem.  [prep fname] should
-    be a function that returns the input from [fname].  Each elemet of
-    [parts] is a pair of functions.  The first converts the output to a string
-    (for example [string_of_int]).  The second executes the given part.
-    Output is given as if done by: 
-    [print_string ( prep fname |> snd |> fst )] *)
+(** [main prep parts] executes an advent of code problem. [prep fname] should be
+    a function that returns the input from [fname]. Each elemet of [parts] is a
+    pair of functions. The first converts the output to a string (for example
+    [string_of_int]). The second executes the given part. Output is given as if
+    done by: [print_string ( prep fname |> snd |> fst )] *)