vec: rework part 1

Cargo.lock

@@ -138,6 +138,12 @@ dependencies = [
  "derive_arbitrary",
 ]
 
+[[package]]
+name = "arc-swap"
+version = "1.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69f7f8c3906b62b754cd5326047894316021dcfe5a194c8ea52bdd94934a3457"
+
 [[package]]
 name = "arrayvec"
 version = "0.7.6"
@@ -548,6 +554,8 @@ dependencies = [
 name = "brk_vec"
 version = "0.0.19"
 dependencies = [
+ "arc-swap",
+ "axum",
  "memmap2",
  "rayon",
  "serde",