diff --git a/third_party/rust_crates/Cargo.lock b/third_party/rust_crates/Cargo.lock
index d2980a7a8e6e6bc1ab10f3f20eedbf427d89c560..13f369f54281e46744dbe5b1b46065a06c7a0e5f 100644
--- a/third_party/rust_crates/Cargo.lock
+++ b/third_party/rust_crates/Cargo.lock
@@ -586,6 +586,7 @@ version = "0.1.0"
 dependencies = [
  "ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "arr_macro 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "arrayvec 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "base64 0.9.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "bincode 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "bit-vec 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/third_party/rust_crates/Cargo.toml b/third_party/rust_crates/Cargo.toml
index 2a395965b3cfdd33495e0b583e54ba41e7f78b60..2a68342b3fbb296b526a272d6c7fd9b77ff7f545 100644
--- a/third_party/rust_crates/Cargo.toml
+++ b/third_party/rust_crates/Cargo.toml
@@ -11,6 +11,7 @@ authors = ["cramertj <cramertj@google.com>"]
 # Keep this sorted alphabetically, please.
 ansi_term = "0.11.0"
 arr_macro = "0.1.0"
+arrayvec = "0.4.10"
 base64 = "0.9"
 bincode = "1"
 bit-vec = "0.5.0"