diff --git a/packages/azure-cosmos-db/azure-cosmos-db.0.1.2/opam b/packages/azure-cosmos-db/azure-cosmos-db.0.1.2/opam
index a8ae16160a9e..684a5e512992 100644
--- a/packages/azure-cosmos-db/azure-cosmos-db.0.1.2/opam
+++ b/packages/azure-cosmos-db/azure-cosmos-db.0.1.2/opam
@@ -14,7 +14,7 @@ depends: [
   "atdgen" {< "2.16.0"}
   "ocsigenserver"
   "ocamlnet"
-  "base64"
+  "base64" {>= "3.0.0"}
   "uri"
   "cohttp"
   "cohttp-lwt-unix"
diff --git a/packages/azure-cosmos-db/azure-cosmos-db.0.1.3/opam b/packages/azure-cosmos-db/azure-cosmos-db.0.1.3/opam
index 8182b076bfd3..6c292a21566f 100644
--- a/packages/azure-cosmos-db/azure-cosmos-db.0.1.3/opam
+++ b/packages/azure-cosmos-db/azure-cosmos-db.0.1.3/opam
@@ -14,7 +14,7 @@ depends: [
   "atdgen" {< "2.16.0"}
   "ocsigenserver"
   "ocamlnet"
-  "base64"
+  "base64" {>= "3.0.0"}
   "uri"
   "cohttp"
   "cohttp-lwt-unix"
diff --git a/packages/azure-cosmos-db/azure-cosmos-db.0.1.4/opam b/packages/azure-cosmos-db/azure-cosmos-db.0.1.4/opam
index 3eec0d117aac..7742f0706674 100644
--- a/packages/azure-cosmos-db/azure-cosmos-db.0.1.4/opam
+++ b/packages/azure-cosmos-db/azure-cosmos-db.0.1.4/opam
@@ -14,7 +14,7 @@ depends: [
   "atdgen" {< "2.16.0"}
   "ocsigenserver"
   "ocamlnet"
-  "base64"
+  "base64" {>= "3.0.0"}
   "uri"
   "cohttp"
   "cohttp-lwt-unix"
diff --git a/packages/azure-cosmos-db/azure-cosmos-db.0.1.5/opam b/packages/azure-cosmos-db/azure-cosmos-db.0.1.5/opam
index 7c36063d3f54..1be1917c890f 100644
--- a/packages/azure-cosmos-db/azure-cosmos-db.0.1.5/opam
+++ b/packages/azure-cosmos-db/azure-cosmos-db.0.1.5/opam
@@ -13,7 +13,7 @@ depends: [
   "lwt_ppx"
   "atdgen" {< "2.16.0"}
   "tls" {< "1.0.0"} | "ssl"
-  "base64"
+  "base64" {>= "3.0.0"}
   "uri"
   "cohttp"
   "cohttp-lwt-unix"
diff --git a/packages/azure-cosmos-db/azure-cosmos-db.0.1.6/opam b/packages/azure-cosmos-db/azure-cosmos-db.0.1.6/opam
index e8e46d7f7dfa..e8289bf73c78 100644
--- a/packages/azure-cosmos-db/azure-cosmos-db.0.1.6/opam
+++ b/packages/azure-cosmos-db/azure-cosmos-db.0.1.6/opam
@@ -13,7 +13,7 @@ depends: [
   "lwt_ppx"
   "atdgen" {< "2.16.0"}
   "tls" {< "1.0.0"} | "ssl"
-  "base64"
+  "base64" {>= "3.0.0"}
   "uri"
   "cohttp"
   "cohttp-lwt-unix"
diff --git a/packages/calculon-web/calculon-web.0.6/opam b/packages/calculon-web/calculon-web.0.6/opam
index d5a9c0c144e4..e85083c726dc 100644
--- a/packages/calculon-web/calculon-web.0.6/opam
+++ b/packages/calculon-web/calculon-web.0.6/opam
@@ -15,6 +15,7 @@ depends: [
   "uri"
   "curly"
   "atdgen" {< "2.16.0"}
+  "yojson" {>= "1.7.0"}
   "lambdasoup"
   "odoc" {with-doc}
   "ocaml" { >= "4.03.0" }
diff --git a/packages/elasticsearch-cli/elasticsearch-cli.0.5/opam b/packages/elasticsearch-cli/elasticsearch-cli.0.5/opam
index 81f0f4a8c77d..9eba5b50b0db 100644
--- a/packages/elasticsearch-cli/elasticsearch-cli.0.5/opam
+++ b/packages/elasticsearch-cli/elasticsearch-cli.0.5/opam
@@ -19,6 +19,7 @@ depends: [
   "lwt_ppx"
   "re2" {>= "v0.9.0"}
   "atdgen" {>= "1.6.0" & < "2.16.0"}
+  "yojson" {>= "1.6.0"}
 ]
 synopsis: "Command-line client for Elasticsearch"
 url {
diff --git a/packages/github/github.4.1.0/opam b/packages/github/github.4.1.0/opam
index 5d4f6ad2741b..07abb21988e8 100644
--- a/packages/github/github.4.1.0/opam
+++ b/packages/github/github.4.1.0/opam
@@ -31,7 +31,7 @@ depends: [
   "cohttp-lwt" {>= "0.99"}
   "lwt" {>= "2.4.4"}
   "atdgen" {>= "2.0.0" & < "2.16.0"}
-  "yojson" {>= "1.6.0"}
+  "yojson" {>= "1.7.0"}
   "stringext"
 ]
 build: [
diff --git a/packages/github/github.4.2.0/opam b/packages/github/github.4.2.0/opam
index 676054b248a3..3cdf59a7be47 100644
--- a/packages/github/github.4.2.0/opam
+++ b/packages/github/github.4.2.0/opam
@@ -37,7 +37,7 @@ depends: [
   "cohttp-lwt" {>= "0.99"}
   "lwt" {>= "2.4.4"}
   "atdgen" {>= "2.0.0" & < "2.16.0"}
-  "yojson" {>= "1.6.0"}
+  "yojson" {>= "1.7.0"}
   "stringext"
 ]
 url {
diff --git a/packages/github/github.4.3.0/opam b/packages/github/github.4.3.0/opam
index 802857c08817..ec682ad056ee 100644
--- a/packages/github/github.4.3.0/opam
+++ b/packages/github/github.4.3.0/opam
@@ -37,7 +37,7 @@ depends: [
   "cohttp-lwt" {>= "0.99"}
   "lwt" {>= "2.4.4"}
   "atdgen" {>= "2.0.0" & < "2.16.0"}
-  "yojson" {>= "1.6.0"}
+  "yojson" {>= "1.7.0"}
   "stringext"
 ]
 url {
diff --git a/packages/github/github.4.3.1/opam b/packages/github/github.4.3.1/opam
index eae8da4b0867..5c3819cd72a1 100644
--- a/packages/github/github.4.3.1/opam
+++ b/packages/github/github.4.3.1/opam
@@ -37,7 +37,7 @@ depends: [
   "cohttp-lwt" {>= "0.99"}
   "lwt" {>= "2.4.4"}
   "atdgen" {>= "2.0.0" & < "2.16.0"}
-  "yojson" {>= "1.6.0"}
+  "yojson" {>= "1.7.0"}
   "stringext"
 ]
 url {
diff --git a/packages/jupyter-kernel/jupyter-kernel.0.6/opam b/packages/jupyter-kernel/jupyter-kernel.0.6/opam
index dbbf53d1296e..615ff13c8756 100644
--- a/packages/jupyter-kernel/jupyter-kernel.0.6/opam
+++ b/packages/jupyter-kernel/jupyter-kernel.0.6/opam
@@ -13,7 +13,7 @@ depends: [
     "result"
     "base-unix"
     "zmq"
-    "atdgen"
+    "atdgen" {< "2.16.0"}
     "yojson" { >= "1.6" }
     "uuidm"
     "lwt"
diff --git a/packages/jupyter-kernel/jupyter-kernel.0.7/opam b/packages/jupyter-kernel/jupyter-kernel.0.7/opam
index 9e9614708d27..cccee7a21d63 100644
--- a/packages/jupyter-kernel/jupyter-kernel.0.7/opam
+++ b/packages/jupyter-kernel/jupyter-kernel.0.7/opam
@@ -16,7 +16,7 @@ depends: [
     "zmq" { >= "5.0" & < "6.0" }
     "zmq-lwt" { >= "5.0" & < "6.0" }
     "atdgen" {< "2.16.0"}
-    "yojson" { >= "1.6" }
+    "yojson" { >= "1.7" }
     "uuidm"
     "lwt"
     "digestif"
diff --git a/packages/libdash/libdash.0.3/opam b/packages/libdash/libdash.0.3/opam
index 80a285ff52e0..1d62d151ea9d 100644
--- a/packages/libdash/libdash.0.3/opam
+++ b/packages/libdash/libdash.0.3/opam
@@ -10,7 +10,7 @@ depends: [
   "ocamlfind" {>= "1.8.0"}
   "ctypes" {>= "0.18.0"}
   "ctypes-foreign" {>= "0.18.0"}
-  "atdgen" {>= "2.3.2"}
+  "atdgen" {>= "2.3.2" & < "2.16.0"}
   "conf-autoconf" {build}
   "conf-aclocal" {build}
   "conf-libtool" {build}
@@ -40,4 +40,3 @@ url {
     "md5=e6d8f86ca8973336f92d2010de21b1ea"
   ]
 }
-
diff --git a/packages/sanddb/sanddb.0.1/opam b/packages/sanddb/sanddb.0.1/opam
index 77c4349f7d13..90a6996a92fe 100644
--- a/packages/sanddb/sanddb.0.1/opam
+++ b/packages/sanddb/sanddb.0.1/opam
@@ -13,7 +13,7 @@ build: [
 depends: [
   "ocaml" {>= "4.04.2"}
   "jbuilder"
-  "atdgen" {>= "1.12.0"}
+  "atdgen" {>= "1.12.0" & < "2.16.0"}
   "lwt" {>= "3.3.0"}
   "uuidm" {>= "0.9.6"}
   "base" {>= "v0.11.0" & < "v0.17"}
diff --git a/packages/uritemplate/uritemplate.0.1.0/opam b/packages/uritemplate/uritemplate.0.1.0/opam
index 5bc058408abf..bbd237a7f578 100644
--- a/packages/uritemplate/uritemplate.0.1.0/opam
+++ b/packages/uritemplate/uritemplate.0.1.0/opam
@@ -8,10 +8,10 @@ homepage: "https://github.com/CorinChappy/uritemplate-ocaml"
 bug-reports: "https://github.com/CorinChappy/uritemplate-ocaml/issues"
 doc: "https://corinchappy.github.io/uritemplate-ocaml/"
 depends: [
-  "dune"
+  "dune" {>= "1.2"}
   "stdcompat" {>= "5"}
   "ounit" {with-test}
-  "atdgen" {with-test}
+  "atdgen" {with-test & < "2.16.0"}
   "odoc" {with-doc}
 ]
 build: [
diff --git a/packages/uritemplate/uritemplate.0.2.0/opam b/packages/uritemplate/uritemplate.0.2.0/opam
index 8faecf08fcd8..c7c81794c4c5 100644
--- a/packages/uritemplate/uritemplate.0.2.0/opam
+++ b/packages/uritemplate/uritemplate.0.2.0/opam
@@ -9,10 +9,10 @@ bug-reports: "https://github.com/CorinChappy/uritemplate-ocaml/issues"
 doc: "https://corinchappy.github.io/uritemplate-ocaml/"
 depends: [
   "ocaml"
-  "dune"
+  "dune" {>= "1.2"}
   "stdcompat" {>= "5"}
   "ounit" {with-test}
-  "atdgen" {with-test}
+  "atdgen" {with-test & < "2.16.0"}
   "odoc" {with-doc}
 ]
 build: [