diff --git a/ruma-identifiers/CHANGELOG.md b/ruma-identifiers/CHANGELOG.md
index 04921662..8cabc0c0 100644
--- a/ruma-identifiers/CHANGELOG.md
+++ b/ruma-identifiers/CHANGELOG.md
@@ -3,6 +3,8 @@
 Bug fixes:
 
 * Fix key algorithm serde (de)serialization
+* Fix `key_algorithms::{DeviceKeyAlgorithm, ServerKeyAlgorithm}` not implementing `Deserialize` and
+  `Serialize` with `default-features = false` + `features = ["serde", …]`
 
 Breaking changes:
 
diff --git a/ruma-identifiers/Cargo.toml b/ruma-identifiers/Cargo.toml
index 89e7292c..321a42c7 100644
--- a/ruma-identifiers/Cargo.toml
+++ b/ruma-identifiers/Cargo.toml
@@ -20,14 +20,15 @@ all-features = true
 rustdoc-args = ["--cfg", "docsrs"]
 
 [features]
-default = ["serde", "ruma-identifiers-validation/serde"]
+default = ["serde"]
+serde = ["serde1", "ruma-identifiers-validation/serde"]
 
 [dependencies]
 either = { version = "1.5.3", optional = true }
 rand = { version = "0.7.3", optional = true }
 ruma-identifiers-macros = { version = "=0.17.3", path = "../ruma-identifiers-macros" }
 ruma-identifiers-validation = { version = "0.1.1", path = "../ruma-identifiers-validation" }
-serde = { version = "1.0.114", optional = true, features = ["derive"] }
+serde1 = { package = "serde", version = "1.0.114", optional = true, features = ["derive"] }
 strum = { version = "0.19.2", features = ["derive"] }
 
 [dev-dependencies]
diff --git a/ruma-identifiers/src/device_id.rs b/ruma-identifiers/src/device_id.rs
index c0e92651..160f82a2 100644
--- a/ruma-identifiers/src/device_id.rs
+++ b/ruma-identifiers/src/device_id.rs
@@ -14,7 +14,7 @@ use crate::generate_localpart;
 /// provided simply for its semantic value.
 #[repr(transparent)]
 #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize), serde(transparent))]
+#[cfg_attr(feature = "serde", derive(serde1::Serialize), serde(transparent, crate = "serde1"))]
 pub struct DeviceId(str);
 
 impl DeviceId {
@@ -112,10 +112,10 @@ impl Display for DeviceId {
 }
 
 #[cfg(feature = "serde")]
-impl<'de> serde::Deserialize<'de> for Box<DeviceId> {
+impl<'de> serde1::Deserialize<'de> for Box<DeviceId> {
     fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
     where
-        D: serde::Deserializer<'de>,
+        D: serde1::Deserializer<'de>,
     {
         crate::deserialize_id(deserializer, "An IP address or hostname")
     }
diff --git a/ruma-identifiers/src/lib.rs b/ruma-identifiers/src/lib.rs
index b056b489..5a9d5bb7 100644
--- a/ruma-identifiers/src/lib.rs
+++ b/ruma-identifiers/src/lib.rs
@@ -12,7 +12,7 @@
 use std::convert::TryFrom;
 
 #[cfg(feature = "serde")]
-use serde::de::{self, Deserialize as _, Deserializer, Unexpected};
+use serde1::de::{self, Deserialize as _, Deserializer, Unexpected};
 
 #[doc(inline)]
 pub use crate::{
diff --git a/ruma-identifiers/src/macros.rs b/ruma-identifiers/src/macros.rs
index 01c69c8c..f7577d6b 100644
--- a/ruma-identifiers/src/macros.rs
+++ b/ruma-identifiers/src/macros.rs
@@ -102,21 +102,21 @@ macro_rules! common_impls {
             }
         }
 
-        #[cfg(feature = "serde")]
-        impl ::serde::Serialize for $id {
+        #[cfg(feature = "serde1")]
+        impl ::serde1::Serialize for $id {
             fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
             where
-                S: ::serde::Serializer,
+                S: ::serde1::Serializer,
             {
                 serializer.serialize_str(self.as_str())
             }
         }
 
-        #[cfg(feature = "serde")]
-        impl<'de> ::serde::Deserialize<'de> for $id {
+        #[cfg(feature = "serde1")]
+        impl<'de> ::serde1::Deserialize<'de> for $id {
             fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
             where
-                D: ::serde::Deserializer<'de>,
+                D: ::serde1::Deserializer<'de>,
             {
                 crate::deserialize_id(deserializer, $desc)
             }
diff --git a/ruma-identifiers/src/room_version_id.rs b/ruma-identifiers/src/room_version_id.rs
index d9bb3775..367fdbe5 100644
--- a/ruma-identifiers/src/room_version_id.rs
+++ b/ruma-identifiers/src/room_version_id.rs
@@ -7,7 +7,7 @@ use std::{
 };
 
 #[cfg(feature = "serde")]
-use serde::{Deserialize, Deserializer, Serialize, Serializer};
+use serde1::{Deserialize, Deserializer, Serialize, Serializer};
 
 use crate::Error;
 
diff --git a/ruma-identifiers/src/server_name.rs b/ruma-identifiers/src/server_name.rs
index fc4e1764..aa401156 100644
--- a/ruma-identifiers/src/server_name.rs
+++ b/ruma-identifiers/src/server_name.rs
@@ -13,7 +13,7 @@ use crate::Error;
 /// A Matrix-spec compliant server name.
 #[repr(transparent)]
 #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize), serde(transparent))]
+#[cfg_attr(feature = "serde", derive(serde1::Serialize), serde(transparent, crate = "serde1"))]
 pub struct ServerName(str);
 
 impl ServerName {
@@ -119,10 +119,10 @@ impl Display for ServerName {
 }
 
 #[cfg(feature = "serde")]
-impl<'de> serde::Deserialize<'de> for Box<ServerName> {
+impl<'de> serde1::Deserialize<'de> for Box<ServerName> {
     fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
     where
-        D: serde::Deserializer<'de>,
+        D: serde1::Deserializer<'de>,
     {
         crate::deserialize_id(deserializer, "An IP address or hostname")
     }