diff --git a/CHANGELOG b/CHANGELOG
deleted file mode 100644
index c2bdccb..0000000
--- a/CHANGELOG
+++ /dev/null
@@ -1,47 +0,0 @@
-# Changelog
-
-## 0.4.1
-
-- persistent_lazy
-- use bin_annot
-
-## 0.4
-
-- API change for persistent
-- more efficient implementation for persistent
-- remove TypeClass
-- API change for min/max (in case the sequence is empty)
-- conversion with Gen
-- use Oasis
-
-## 0.3.7
-
-- decreasing int range
-- printing functions
-
-## 0.3.6.1
-
-- documentation
-- bugfixes
-
-## 0.3.6
-
-- fmap
-- functors to adapt Set and Map
-
-## 0.3.5
-
-- tests and benchmarks
-- join combinator
-- optimization for Sequence.persistent
-
-## 0.3.4
-
-- sort, uniq, group and sort_uniq combinators implemented
-- some conversion functions that use Sequence.t2
-- infix operators in Sequence.Infix
-- Sequence.t2 type for efficient iteration on pairs of elements
-- some combinators are adapted to Sequence.t2
-- zip, unzip and zip_i to convert between t and t2
-- added scan combinator
-
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..08c0e5a
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,65 @@
+# Changelog
+
+## 0.5
+
+- conversion with `klist`
+- add monadic, choice and applicative infix operators and `>|=`
+- add several functions:
+  * `product2`
+  * `find`, `mem`
+  * `doubleton`, `cons`, `snoc`
+  * `drop_while`, `take_while`...
+  * `concat_str`
+- aliases to existing functions
+- use `delimcc` in a new module, `SequenceInvert`, in order to reverse the
+  control flow (here with conversion to Gen)
+- fix examples, tests and doc (about `product`)
+- reading benchmark for persistent sequences.
+- replace `Bench` with `Benchmark`
+
+## 0.4.1
+
+- `persistent_lazy`
+- use bin_annot
+
+## 0.4
+
+- API change for `persistent`
+- more efficient implementation for `persistent`
+- remove `TypeClass`
+- API change for `min`/`max` (in case the sequence is empty)
+- conversion with `Gen`
+- use Oasis
+
+## 0.3.7
+
+- decreasing int range
+- printing functions
+
+## 0.3.6.1
+
+- documentation
+- bugfixes
+
+## 0.3.6
+
+- `fmap`
+- functors to adapt `Set` and `Map`
+
+## 0.3.5
+
+- tests and benchmarks
+- `join` combinator
+- optimization for `Sequence.persistent`
+
+## 0.3.4
+
+- `sort`, `uniq`, `group` and `sort_uniq` combinators implemented
+- some conversion functions that use `Sequence.t2`
+- infix operators in `Sequence.Infix`
+- `Sequence.t2` type for efficient iteration on pairs of elements
+- some combinators are adapted to `Sequence.t2`
+- `zip`, `unzip` and `zip_i` to convert between `t` and `t2`
+- added `scan` combinator
+
+note: git log --no-merges previous_version..HEAD --pretty=%s
diff --git a/Makefile b/Makefile
index 8b51c6e..8a1e499 100644
--- a/Makefile
+++ b/Makefile
@@ -49,4 +49,10 @@ examples:
 push_doc: all doc
 	scp -r sequence.docdir/* cedeela.fr:~/simon/root/software/sequence/
 
-.PHONY: benchs tests examples
+VERSION=$(shell awk '/Version:/ {print $$2}' _oasis)
+
+update_next_tag:
+	@echo "update version to $(VERSION)..."
+	sed -i "s/NEXT_VERSION/$(VERSION)/g" *.ml *.mli
+
+.PHONY: benchs tests examples update_next_tag push_doc
diff --git a/_oasis b/_oasis
index ed0be89..3e48dbe 100644
--- a/_oasis
+++ b/_oasis
@@ -1,6 +1,6 @@
 OASISFormat: 0.4
 Name:        sequence
-Version:     0.4.1
+Version:     0.5
 Homepage:    https://github.com/c-cube/sequence
 Authors:     Simon Cruanes
 License:     BSD-2-clause
diff --git a/sequence.mli b/sequence.mli
index 9f4f260..e2691a9 100644
--- a/sequence.mli
+++ b/sequence.mli
@@ -139,11 +139,11 @@ val exists : ('a -> bool) -> 'a t -> bool
 val mem : ?eq:('a -> 'a -> bool) -> 'a -> 'a t -> bool
   (** Is the value a member of the sequence?
       @param eq the equality predicate to use (default [(=)])
-      @since NEXT_VERSION *)
+      @since 0.5 *)
 
 val find : ('a -> 'b option) -> 'a t -> 'b option
   (** Find the first element on which the function doesn't return [None]
-      @since NEXT_VERSION *)
+      @since 0.5 *)
 
 val length : 'a t -> int
   (** How long is the sequence? Forces the sequence. *)
@@ -172,14 +172,14 @@ val flatMap : ('a -> 'b t) -> 'a t -> 'b t
 
 val flat_map : ('a -> 'b t) -> 'a t -> 'b t
   (** Alias to {!flatMap} with a more explicit name
-      @since NEXT_VERSION *)
+      @since 0.5 *)
 
 val fmap : ('a -> 'b option) -> 'a t -> 'b t
   (** Specialized version of {!flatMap} for options.  *)
 
 val filter_map : ('a -> 'b option) -> 'a t -> 'b t
   (** Alias to {!fmap} with a more explicit name
-      @since NEXT_VERSION *)
+      @since 0.5 *)
 
 val intersperse : 'a -> 'a t -> 'a t
   (** Insert the single element between every element of the sequence *)
@@ -228,7 +228,7 @@ val product : 'a t -> 'b t -> ('a * 'b) t
 
 val product2 : 'a t -> 'b t -> ('a, 'b) t2
   (** Binary version of {!product}. Same requirements.
-      @since NEXT_VERSION *)
+      @since 0.5 *)
 
 val join : join_row:('a -> 'b -> 'c option) -> 'a t -> 'b t -> 'c t
   (** [join ~join_row a b] combines every element of [a] with every
@@ -369,7 +369,7 @@ val to_str :  char t -> string
 val concat_str : string t -> string
   (** Concatenate strings together, eagerly.
       Also see {!intersperse} to add a separator.
-      @since NEXT_VERSION *)
+      @since 0.5 *)
 
 exception OneShotSequence
   (** Raised when the user tries to iterate several times on