diff --git a/cabal.project b/cabal.project
index f49f3537..935bc01b 100644
--- a/cabal.project
+++ b/cabal.project
@@ -8,7 +8,7 @@ source-repository-package
 source-repository-package
     type: git
     location: https://github.com/nomeata/haskell-candid
-    tag: bff9fcf23e6c60bb8cd7c1ac1ae3d39f6fc05ec0
+    tag: 0.4
 
 source-repository-package
     type: git
diff --git a/cabal.project.freeze b/cabal.project.freeze
index 7ab8a135..07428ab5 100644
--- a/cabal.project.freeze
+++ b/cabal.project.freeze
@@ -41,7 +41,7 @@ constraints: any.FloatingHex ==0.5,
              any.bytes ==0.17.1,
              any.bytestring ==0.10.12.1,
              any.call-stack ==0.4.0,
-             any.candid ==0.3.1,
+             any.candid ==0.4,
              any.case-insensitive ==1.2.1.0,
              any.cborg ==0.2.7.0,
              any.cereal ==0.5.8.2,
diff --git a/nix/sources.json b/nix/sources.json
index b2bb7cdd..ea382531 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -6,10 +6,10 @@
         "homepage": null,
         "owner": "nomeata",
         "repo": "haskell-candid",
-        "rev": "bff9fcf23e6c60bb8cd7c1ac1ae3d39f6fc05ec0",
-        "sha256": "0zw9zr4gipaa8vqki6y75gq05hy9cn3c5f33q41allj2kl5v8a9j",
+        "rev": "87a4f01eb9cb93c827a0a7f5f29af0ee19135308",
+        "sha256": "0mcmj62x49k241k5rpc7j37yczjlcsgyssjwy1ncfs8ss0b8b03r",
         "type": "tarball",
-        "url": "https://github.com/nomeata/haskell-candid/archive/bff9fcf23e6c60bb8cd7c1ac1ae3d39f6fc05ec0.tar.gz",
+        "url": "https://github.com/nomeata/haskell-candid/archive/87a4f01eb9cb93c827a0a7f5f29af0ee19135308.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "leb128-cereal": {