diff --git a/Cargo.lock b/Cargo.lock
index e2107dcd..79924dea 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -86,15 +86,6 @@ dependencies = [
  "zeroize",
 ]
 
-[[package]]
-name = "der"
-version = "0.2.10"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce93ba4502a73722aa4b955d97f4b1bd26f4f8da74315399ca58fb88fe2bdaae"
-dependencies = [
- "typenum",
-]
-
 [[package]]
 name = "der"
 version = "0.3.0"
@@ -102,6 +93,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7516ff8d4f25ddd138caba1b7836ceb3ddd07660213b50e83ae3165320257ba2"
 dependencies = [
  "const-oid",
+ "typenum",
 ]
 
 [[package]]
@@ -117,7 +109,7 @@ dependencies = [
 name = "ecdsa"
 version = "0.11.0-pre.2"
 dependencies = [
- "der 0.2.10",
+ "der",
  "elliptic-curve",
  "hex-literal",
  "hmac",
@@ -260,7 +252,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b813f58dc6e5d1820868a3c3df3a7ae7852aa2d3d18e98f0d6b20ddd01fe25d7"
 dependencies = [
  "base64ct",
- "der 0.3.0",
+ "der",
  "spki",
  "zeroize",
 ]
@@ -377,7 +369,7 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9dae7e047abc519c96350e9484a96c6bf1492348af912fd3446dd2dc323f6268"
 dependencies = [
- "der 0.3.0",
+ "der",
 ]
 
 [[package]]
diff --git a/ecdsa/Cargo.toml b/ecdsa/Cargo.toml
index 5bbc2e2f..d215c358 100644
--- a/ecdsa/Cargo.toml
+++ b/ecdsa/Cargo.toml
@@ -14,7 +14,7 @@ categories = ["cryptography", "no-std"]
 keywords   = ["crypto", "ecc", "nist", "secp256k1", "signature"]
 
 [dependencies]
-der = { version = "0.2", optional = true, features = ["big-uint"] }
+der = { version = "0.3", optional = true, features = ["big-uint"] }
 elliptic-curve = { version = "0.9", default-features = false }
 hmac = { version = "0.10", optional = true, default-features = false }
 signature = { version = ">= 1.3.0, < 1.4.0", default-features = false, features = ["rand-preview"] }
diff --git a/ecdsa/src/der.rs b/ecdsa/src/der.rs
index 4e7c9647..1999c24c 100644
--- a/ecdsa/src/der.rs
+++ b/ecdsa/src/der.rs
@@ -1,9 +1,7 @@
 //! Support for ECDSA signatures encoded as ASN.1 DER.
 
-pub use der::BigUIntSize;
-
 use crate::{
-    generic_array::{ArrayLength, GenericArray},
+    generic_array::{typenum::NonZero, ArrayLength, GenericArray},
     Error,
 };
 use core::{
@@ -52,7 +50,7 @@ const ENCODING_ERR_MSG: &str = "DER encoding error";
 pub struct Signature<C>
 where
     C: Curve,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
@@ -69,7 +67,7 @@ where
 impl<C> signature::Signature for Signature<C>
 where
     C: Curve,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
@@ -83,7 +81,7 @@ where
 impl<C> Signature<C>
 where
     C: Curve,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
@@ -111,7 +109,8 @@ where
         let mut bytes = SignatureBytes::<C>::default();
         let mut encoder = der::Encoder::new(&mut bytes);
 
-        encoder.sequence(&[&r, &s]).expect(ENCODING_ERR_MSG);
+        encoder.message(&[&r, &s]).expect(ENCODING_ERR_MSG);
+
         encoder
             .finish()
             .expect(ENCODING_ERR_MSG)
@@ -133,7 +132,7 @@ where
 impl<C> AsRef<[u8]> for Signature<C>
 where
     C: Curve,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
@@ -145,7 +144,7 @@ where
 impl<C> fmt::Debug for Signature<C>
 where
     C: Curve,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
@@ -160,7 +159,7 @@ where
 impl<C> TryFrom<&[u8]> for Signature<C>
 where
     C: Curve,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
@@ -208,7 +207,7 @@ fn find_scalar_range(outer: &[u8], inner: &[u8]) -> Result<Range<usize>, Error>
 impl<C> signature::PrehashSignature for Signature<C>
 where
     C: Curve + crate::hazmat::DigestPrimitive,
-    C::FieldSize: Add + ArrayLength<u8> + BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,
 {
diff --git a/ecdsa/src/lib.rs b/ecdsa/src/lib.rs
index 04dd9173..413e89d1 100644
--- a/ecdsa/src/lib.rs
+++ b/ecdsa/src/lib.rs
@@ -110,6 +110,9 @@ use generic_array::{sequence::Concat, typenum::Unsigned, ArrayLength, GenericArr
 #[cfg(feature = "arithmetic")]
 use elliptic_curve::{ff::PrimeField, NonZeroScalar, ProjectiveArithmetic, Scalar};
 
+#[cfg(feature = "der")]
+use generic_array::typenum::NonZero;
+
 /// Size of a fixed sized signature for the given elliptic curve.
 pub type SignatureSize<C> = <<C as elliptic_curve::Curve>::FieldSize as Add>::Output;
 
@@ -159,7 +162,7 @@ where
     #[cfg_attr(docsrs, doc(cfg(feature = "der")))]
     pub fn from_der(bytes: &[u8]) -> Result<Self, Error>
     where
-        C::FieldSize: Add + ArrayLength<u8> + der::BigUIntSize,
+        C::FieldSize: Add + ArrayLength<u8> + NonZero,
         der::MaxSize<C>: ArrayLength<u8>,
         <C::FieldSize as Add>::Output: Add<der::MaxOverhead> + ArrayLength<u8>,
     {
@@ -171,7 +174,7 @@ where
     #[cfg_attr(docsrs, doc(cfg(feature = "der")))]
     pub fn to_der(&self) -> der::Signature<C>
     where
-        C::FieldSize: Add + ArrayLength<u8> + der::BigUIntSize,
+        C::FieldSize: Add + ArrayLength<u8> + NonZero,
         der::MaxSize<C>: ArrayLength<u8>,
         <C::FieldSize as Add>::Output: Add<der::MaxOverhead> + ArrayLength<u8>,
     {
@@ -293,7 +296,7 @@ where
 impl<C> TryFrom<der::Signature<C>> for Signature<C>
 where
     C: Curve + CheckSignatureBytes,
-    C::FieldSize: Add + ArrayLength<u8> + der::BigUIntSize,
+    C::FieldSize: Add + ArrayLength<u8> + NonZero,
     der::MaxSize<C>: ArrayLength<u8>,
     <C::FieldSize as Add>::Output: Add<der::MaxOverhead> + ArrayLength<u8>,
 {