diff --git a/Cargo.toml b/Cargo.toml
index 94263be..58388c6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 
 name = "secp256k1"
-version = "0.16.0"
+version = "0.16.1"
 authors = [ "Dawid Ciężarkiewicz <dpc@ucore.info>",
             "Andrew Poelstra <apoelstra@wpsoftware.net>" ]
 license = "CC0-1.0"
@@ -41,10 +41,10 @@ dont_replace_c_symbols = []
 fuzztarget = []
 
 [dev-dependencies]
-rand = "0.6"
-rand_core = "0.4"
-serde_test = "1.0"
-bitcoin_hashes = "0.7"
+rand = "0.6.5"
+rand_core = "0.4.2"
+serde_test = "1.0.102"
+bitcoin_hashes = "0.7.1"
 
 [dependencies.rand]
 version = "0.6"
@@ -65,4 +65,4 @@ name = "sign_verify"
 
 [[example]]
 name = "generate_keys"
-required-features = ["rand"]
\ No newline at end of file
+required-features = ["rand"]
diff --git a/src/key.rs b/src/key.rs
index 38f3cdf..ba1d221 100644
--- a/src/key.rs
+++ b/src/key.rs
@@ -619,13 +619,13 @@ mod test {
             fn next_u64(&mut self) -> u64 {
                 self.next_u32() as u64
             }
-            fn try_fill_bytes(&mut self, _dest: &mut [u8]) -> Result<(), Error> {
-                Err(Error::new(ErrorKind::Unavailable, "not implemented"))
-            }
-
             fn fill_bytes(&mut self, dest: &mut [u8]) {
                 impls::fill_bytes_via_next(self, dest);
             }
+
+            fn try_fill_bytes(&mut self, _dest: &mut [u8]) -> Result<(), Error> {
+                Err(Error::new(ErrorKind::Unavailable, "not implemented"))
+            }
         }
 
         let s = Secp256k1::new();
diff --git a/src/macros.rs b/src/macros.rs
index 6a8354f..c360796 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -147,9 +147,9 @@ macro_rules! impl_pretty_debug {
     ($thing:ident) => {
         impl ::core::fmt::Debug for $thing {
             fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
-                try!(write!(f, "{}(", stringify!($thing)));
+                write!(f, "{}(", stringify!($thing))?;
                 for i in self[..].iter().cloned() {
-                    try!(write!(f, "{:02x}", i));
+                    write!(f, "{:02x}", i)?;
                 }
                 write!(f, ")")
             }
@@ -162,7 +162,7 @@ macro_rules! impl_raw_debug {
         impl ::core::fmt::Debug for $thing {
             fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
                 for i in self[..].iter().cloned() {
-                    try!(write!(f, "{:02x}", i));
+                    write!(f, "{:02x}", i)?;
                 }
                 Ok(())
             }