diff --git a/src/kmer.gleam b/src/kmer.gleam
index 2bcfb24..0d2f8ff 100644
--- a/src/kmer.gleam
+++ b/src/kmer.gleam
@@ -102,7 +102,7 @@ fn decode_map(
 ) -> DecoderResult(List(#(DecodedValue, DecodedValue))) {
   use #(length, rest) <- try(decode_int(bits))
   use #(entries, remainder) <- try(decode_next_n([], rest, length * 2))
-  use pairs <- try(into_pairs(entries))
+  use pairs <- try(into_pairs([], entries))
   Ok(#(pairs, remainder))
 }
 
@@ -128,18 +128,14 @@ fn decode_simple(bits: BitArray) -> DecodeResult {
   }
 }
 
-fn into_pairs(list: List(a)) -> Result(List(#(a, a)), DecodeError) {
-  into_pairs_aggr([], list)
-}
-
-fn into_pairs_aggr(
+fn into_pairs(
   accum: List(#(a, a)),
   remaining: List(a),
 ) -> Result(List(#(a, a)), DecodeError) {
   case remaining {
     [] -> Ok(reverse(accum))
     [_] -> Error(Malformed)
-    [key, value, ..rest] -> into_pairs_aggr([#(key, value), ..accum], rest)
+    [key, value, ..rest] -> into_pairs([#(key, value), ..accum], rest)
   }
 }