diff --git a/_oasis b/_oasis
index 40bbc4d4..86ba9536 100644
--- a/_oasis
+++ b/_oasis
@@ -1,6 +1,6 @@
 OASISFormat: 0.4
 Name:        containers
-Version:     0.22
+Version:     0.22.1
 Homepage:    https://github.com/c-cube/ocaml-containers
 Authors:     Simon Cruanes
 License:     BSD-2-clause
diff --git a/opam b/opam
index cb986615..bc7dbeff 100644
--- a/opam
+++ b/opam
@@ -1,6 +1,6 @@
 opam-version: "1.2"
 name: "containers"
-version: "0.21"
+version: "0.22.1"
 author: "Simon Cruanes"
 maintainer: "simon.cruanes@inria.fr"
 build: [
diff --git a/src/advanced/CCLinq.ml b/src/advanced/CCLinq.ml
index 06d2fe0e..a04701c8 100644
--- a/src/advanced/CCLinq.ml
+++ b/src/advanced/CCLinq.ml
@@ -212,7 +212,7 @@ module PMap = struct
     seq
 
   let flatten_l m =
-    let seq = Sequence.flatMap
+    let seq = Sequence.flat_map
         (fun (k,v) -> Sequence.map (fun v' -> k,v') (Sequence.of_list v))
         m.to_seq
     in
diff --git a/src/core/META b/src/core/META
index d39e8bdb..53089f3b 100644
--- a/src/core/META
+++ b/src/core/META
@@ -1,6 +1,6 @@
 # OASIS_START
-# DO NOT EDIT (digest: a16455ed7ae2b2e8c42add2f54bd446e)
-version = "0.22"
+# DO NOT EDIT (digest: e46e29f7bdcb542070b9b01d13e70831)
+version = "0.22.1"
 description = "A modular standard library focused on data structures."
 requires = "bytes result"
 archive(byte) = "containers.cma"
@@ -9,7 +9,7 @@ archive(native) = "containers.cmxa"
 archive(native, plugin) = "containers.cmxs"
 exists_if = "containers.cma"
 package "unix" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "bytes unix"
  archive(byte) = "containers_unix.cma"
@@ -20,7 +20,7 @@ package "unix" (
 )
 
 package "top" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires =
  "compiler-libs.common containers containers.data containers.bigarray containers.string containers.unix containers.sexp containers.iter"
@@ -32,7 +32,7 @@ package "top" (
 )
 
 package "thread" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "containers threads"
  archive(byte) = "containers_thread.cma"
@@ -43,7 +43,7 @@ package "thread" (
 )
 
 package "string" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "bytes"
  archive(byte) = "containers_string.cma"
@@ -54,7 +54,7 @@ package "string" (
 )
 
 package "sexp" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "bytes"
  archive(byte) = "containers_sexp.cma"
@@ -65,7 +65,7 @@ package "sexp" (
 )
 
 package "iter" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  archive(byte) = "containers_iter.cma"
  archive(byte, plugin) = "containers_iter.cma"
@@ -75,7 +75,7 @@ package "iter" (
 )
 
 package "io" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "bytes"
  archive(byte) = "containers_io.cma"
@@ -86,7 +86,7 @@ package "io" (
 )
 
 package "data" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "bytes"
  archive(byte) = "containers_data.cma"
@@ -97,7 +97,7 @@ package "data" (
 )
 
 package "bigarray" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "containers bigarray bytes"
  archive(byte) = "containers_bigarray.cma"
@@ -108,7 +108,7 @@ package "bigarray" (
 )
 
 package "advanced" (
- version = "0.22"
+ version = "0.22.1"
  description = "A modular standard library focused on data structures."
  requires = "containers sequence"
  archive(byte) = "containers_advanced.cma"