diff --git a/Cargo.lock b/Cargo.lock
index 6e1107d22..87c5b635c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2755,6 +2755,7 @@ dependencies = [
  "hex",
  "hex-literal",
  "rand 0.8.4",
+ "rand_chacha 0.3.1",
  "serde",
  "signature",
  "thiserror",
diff --git a/crates/tor-netdir/Cargo.toml b/crates/tor-netdir/Cargo.toml
index 41651e43f..6a3810540 100644
--- a/crates/tor-netdir/Cargo.toml
+++ b/crates/tor-netdir/Cargo.toml
@@ -47,3 +47,4 @@ tracing = "0.1.26"
 hex = "0.4.3"
 hex-literal = "0.3.1"
 tor-netdoc = { path="../tor-netdoc", version = "0.0.2", features=["build_docs"] }
+rand_chacha = "0.3.1"
\ No newline at end of file
diff --git a/crates/tor-netdir/src/testing.rs b/crates/tor-netdir/src/testing.rs
index c95607851..9ffd5b691 100644
--- a/crates/tor-netdir/src/testing.rs
+++ b/crates/tor-netdir/src/testing.rs
@@ -16,12 +16,9 @@ mod imp {
     pub(crate) fn get_rng() -> impl rand::Rng {
         // When stochastic tests aren't enabled, we use a RNG seeded
         // with a fixed value and a small number of iterators for each test.
-        //
-        // XXXX: Note that the StdRng is not guaranteed to be
-        // reproducible across rust stdlib versions; an upgrade might break
-        // these tests.
         use rand::SeedableRng;
-        rand::rngs::StdRng::from_seed(
+        // Use this RNG to make the tests reproducible.
+        rand_chacha::ChaCha12Rng::from_seed(
             // Fun facts:
             // The Julius Tote was a mechanical computer and point-of-sale
             // system from the 1920s that used horses as an RNG.