diff --git a/CHANGES.md b/CHANGES.md
index 5561af63..351de987 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,4 +1,12 @@
 
+## 0.20
+
+- eio backend, second try (#95)
+- hardening bugfixes
+- feat WS: abstraction for critical section
+- feat route: add `to_url`, to produce a URL path from a route
+- fix some warnings
+
 ## 0.19
 
 - feat(headers): `set` will not reallocate whole list if not needed
diff --git a/dune-project b/dune-project
index 5eaf279c..a1e53b90 100644
--- a/dune-project
+++ b/dune-project
@@ -1,51 +1,73 @@
 (lang dune 3.2)
+
 (name tiny_httpd)
+
 (generate_opam_files true)
 
 (authors c-cube)
+
 (maintainers c-cube)
-(version 0.19)
-(source (github c-cube/tiny_httpd))
+
+(version 0.20)
+
+(source
+ (github c-cube/tiny_httpd))
+
 (homepage https://github.com/c-cube/tiny_httpd/)
+
 (license MIT)
 
 (package
-  (name tiny_httpd)
-  (synopsis "Minimal HTTP server using threads")
-  (tags (http thread server tiny_httpd http_of_dir simplehttpserver))
-  (depopts
-    logs
-    magic-mime
-    (mtime (>= 2.0)))
-  (depends
-    seq
-    base-threads
-    result
-    hmap
-    (iostream (>= 0.2))
-    (ocaml (>= 4.13))
-    (odoc :with-doc)
-    (logs :with-test)
-    (conf-libcurl :with-test)
-    (ptime :with-test)
-    (qcheck-core (and (>= 0.91) :with-test))))
+ (name tiny_httpd)
+ (synopsis "Minimal HTTP server using threads")
+ (tags
+  (http thread server tiny_httpd http_of_dir simplehttpserver))
+ (depopts
+  logs
+  magic-mime
+  (mtime
+   (>= 2.0)))
+ (depends
+  seq
+  base-threads
+  result
+  hmap
+  (iostream
+   (>= 0.2))
+  (ocaml
+   (>= 4.13))
+  (odoc :with-doc)
+  (logs :with-test)
+  (conf-libcurl :with-test)
+  (ptime :with-test)
+  (qcheck-core
+   (and
+    (>= 0.91)
+    :with-test))))
 
 (package
-  (name tiny_httpd_camlzip)
-  (synopsis "Interface to camlzip for tiny_httpd")
-  (depends
-    (tiny_httpd (= :version))
-    (camlzip (>= 1.06))
-    (iostream-camlzip (>= 0.2.1))
-    (logs :with-test)
-    (odoc :with-doc)))
+ (name tiny_httpd_camlzip)
+ (synopsis "Interface to camlzip for tiny_httpd")
+ (depends
+  (tiny_httpd
+   (= :version))
+  (camlzip
+   (>= 1.06))
+  (iostream-camlzip
+   (>= 0.2.1))
+  (logs :with-test)
+  (odoc :with-doc)))
 
 (package
-  (name tiny_httpd_eio)
-  (synopsis "Use eio for tiny_httpd")
-  (depends
-    (tiny_httpd (= :version))
-    (eio (and (>= 1.0) (< 2.0)))
-    base-unix
-    (logs :with-test)
-    (odoc :with-doc)))
+ (name tiny_httpd_eio)
+ (synopsis "Use eio for tiny_httpd")
+ (depends
+  (tiny_httpd
+   (= :version))
+  (eio
+   (and
+    (>= 1.0)
+    (< 2.0)))
+  base-unix
+  (logs :with-test)
+  (odoc :with-doc)))
diff --git a/tiny_httpd.opam b/tiny_httpd.opam
index 7fbbe020..d7f7347c 100644
--- a/tiny_httpd.opam
+++ b/tiny_httpd.opam
@@ -1,6 +1,6 @@
 # This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-version: "0.19"
+version: "0.20"
 synopsis: "Minimal HTTP server using threads"
 maintainer: ["c-cube"]
 authors: ["c-cube"]
diff --git a/tiny_httpd_camlzip.opam b/tiny_httpd_camlzip.opam
index 09d3511a..38c94e66 100644
--- a/tiny_httpd_camlzip.opam
+++ b/tiny_httpd_camlzip.opam
@@ -1,6 +1,6 @@
 # This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-version: "0.19"
+version: "0.20"
 synopsis: "Interface to camlzip for tiny_httpd"
 maintainer: ["c-cube"]
 authors: ["c-cube"]
diff --git a/tiny_httpd_eio.opam b/tiny_httpd_eio.opam
index 51f27557..4156ea02 100644
--- a/tiny_httpd_eio.opam
+++ b/tiny_httpd_eio.opam
@@ -1,6 +1,6 @@
 # This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-version: "0.19"
+version: "0.20"
 synopsis: "Use eio for tiny_httpd"
 maintainer: ["c-cube"]
 authors: ["c-cube"]