diff --git a/ocamlrep/Cargo.toml b/ocamlrep/Cargo.toml
index a604414c..1b2226af 100644
--- a/ocamlrep/Cargo.toml
+++ b/ocamlrep/Cargo.toml
@@ -16,7 +16,7 @@ doctest = false
 [dependencies]
 bstr = { version = "1.4.0", features = ["serde", "std", "unicode"] }
 bumpalo = { version = "3.14.0", features = ["allocator_api", "collections"] }
-indexmap = { version = "2.1.0", features = ["arbitrary", "rayon", "serde"] }
+indexmap = { version = "2.2.6", features = ["arbitrary", "rayon", "serde"] }
 ocamlrep_derive = { path = "../ocamlrep_derive" }
 rustc-hash = "1.1.0"
 serde = { version = "1.0.185", features = ["derive", "rc"] }
diff --git a/rust_to_ocaml/rust_to_ocaml/Cargo.toml b/rust_to_ocaml/rust_to_ocaml/Cargo.toml
index b41eb040..5a465dbb 100644
--- a/rust_to_ocaml/rust_to_ocaml/Cargo.toml
+++ b/rust_to_ocaml/rust_to_ocaml/Cargo.toml
@@ -20,7 +20,7 @@ attr_parser = { path = "../attr_parser" }
 clap = { version = "3.2.25", features = ["derive", "env", "regex", "unicode", "wrap_help"] }
 convert_case = "0.4.0"
 derive_more = "0.99.17"
-indexmap = { version = "2.1.0", features = ["arbitrary", "rayon", "serde"] }
+indexmap = { version = "2.2.6", features = ["arbitrary", "rayon", "serde"] }
 serde = { version = "1.0.185", features = ["derive", "rc"] }
 signed_source = { path = "../../signed_source" }
 syn = { version = "1.0.109", features = ["extra-traits", "fold", "full", "visit", "visit-mut"] }