diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 5135c9ca6c..8d37c2f1b5 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -28,6 +28,10 @@ jobs:
           - rust: 1.41.1
             env:
               AS_DEPENDENCY: true
+          - rust: 1.47
+            env:
+              AS_DEPENDENCY: true
+              DO_NO_STD: true
     steps:
       - name: Checkout Crate
         uses: actions/checkout@v2
diff --git a/.gitignore b/.gitignore
index bd1795fa1e..a8920838f9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 target
 Cargo.lock
+dep_test
 
 #fuzz
 fuzz/hfuzz_target
diff --git a/README.md b/README.md
index decc4fc132..d9ac6412b2 100644
--- a/README.md
+++ b/README.md
@@ -77,7 +77,8 @@ please join us in
 
 ## Minimum Supported Rust Version (MSRV)
 
-This library should always compile with any combination of features on **Rust 1.29**.
+This library should always compile with any combination of features (minus
+`no-std`) on **Rust 1.41.1** or **Rust 1.47** with `no-std`.
 
 Because some dependencies have broken the build in minor/patch releases, to
 compile with 1.29.0 you will need to run the following version-pinning command:
diff --git a/src/util/bip32.rs b/src/util/bip32.rs
index 65a973f5f3..611ee005ae 100644
--- a/src/util/bip32.rs
+++ b/src/util/bip32.rs
@@ -74,7 +74,8 @@ impl fmt::Debug for ExtendedPrivKey {
             .field("parent_fingerprint", &self.parent_fingerprint)
             .field("child_number", &self.child_number)
             .field("chain_code", &self.chain_code)
-            .finish_non_exhaustive()
+            .field("private_key", &"[SecretKey]")
+            .finish()
     }
 }