diff --git a/README.md b/README.md
index 109ec1dce..5cfe2c98a 100644
--- a/README.md
+++ b/README.md
@@ -148,8 +148,8 @@ alias build-docs='RUSTDOCFLAGS="--cfg docsrs" cargo +nightly rustdoc --features=
 Unit and integration tests are available for those interested, along with benchmarks. For project
 developers, especially new contributors looking for something to work on, we do:
 
-- Fuzz testing with [`Hongfuzz`](https://github.com/rust-fuzz/honggfuzz-rs)
-- Mutation testing with [`Mutagen`](https://github.com/llogiq/mutagen)
+- Fuzz testing with [`Honggfuzz`](https://github.com/rust-fuzz/honggfuzz-rs)
+- Mutation testing with [`cargo-mutants`](https://github.com/sourcefrog/cargo-mutants)
 - Code verification with [`Kani`](https://github.com/model-checking/kani)
 
 There are always more tests to write and more bugs to find, contributions to our testing efforts
@@ -167,9 +167,9 @@ bench marks use: `RUSTFLAGS='--cfg=bench' cargo +nightly bench`.
 
 ### Mutation tests
 
-We have started doing mutation testing with [mutagen](https://github.com/llogiq/mutagen). To run
-these tests first install the latest dev version with `cargo +nightly install --git https://github.com/llogiq/mutagen`
-then run with `RUSTFLAGS='--cfg=mutate' cargo +nightly mutagen`.
+We are doing mutation testing with [cargo-mutants](https://github.com/sourcefrog/cargo-mutants). To run
+these tests first install with `cargo install --locked cargo-mutants` then run with `cargo mutants --in-place --no-shuffle`.
+Note that running these mutation tests will take on the order of 10's of minutes.
 
 ### Code verification
 
diff --git a/bitcoin/Cargo.toml b/bitcoin/Cargo.toml
index d792a3a7e..7784efff7 100644
--- a/bitcoin/Cargo.toml
+++ b/bitcoin/Cargo.toml
@@ -95,4 +95,4 @@ name = "io"
 required-features = ["std"]
 
 [lints.rust]
-unexpected_cfgs = { level = "deny", check-cfg = ['cfg(bench)', 'cfg(fuzzing)', 'cfg(kani)', 'cfg(mutate)'] }
+unexpected_cfgs = { level = "deny", check-cfg = ['cfg(bench)', 'cfg(fuzzing)', 'cfg(kani)'] }
diff --git a/primitives/Cargo.toml b/primitives/Cargo.toml
index 3a7feefc9..b8b0bdd4c 100644
--- a/primitives/Cargo.toml
+++ b/primitives/Cargo.toml
@@ -38,9 +38,6 @@ bincode = "1.3.1"
 all-features = true
 rustdoc-args = ["--cfg", "docsrs"]
 
-[lints.rust]
-unexpected_cfgs = { level = "deny", check-cfg = ['cfg(mutate)'] }
-
 [lints.clippy]
 # Exclude lints we don't think are valuable.
 needless_question_mark = "allow" # https://github.com/rust-bitcoin/rust-bitcoin/pull/2134