diff --git a/matrix_sdk/Cargo.toml b/matrix_sdk/Cargo.toml
index 44e3cfbf..805283fe 100644
--- a/matrix_sdk/Cargo.toml
+++ b/matrix_sdk/Cargo.toml
@@ -20,6 +20,7 @@ default = ["encryption", "sqlite_cryptostore", "messages", "native-tls"]
 messages = ["matrix-sdk-base/messages"]
 encryption = ["matrix-sdk-base/encryption", "dashmap"]
 sqlite_cryptostore = ["matrix-sdk-base/sqlite_cryptostore"]
+unstable-synapse-quirks = ["matrix-sdk-base/unstable-synapse-quirks"]
 native-tls = ["reqwest/native-tls"]
 rustls-tls = ["reqwest/rustls-tls"]
 socks = ["reqwest/socks"]
diff --git a/matrix_sdk/src/lib.rs b/matrix_sdk/src/lib.rs
index d4dce80b..3dd243b5 100644
--- a/matrix_sdk/src/lib.rs
+++ b/matrix_sdk/src/lib.rs
@@ -24,6 +24,8 @@
 //! keys. If this is disabled and `encryption` support is enabled the keys will
 //! by default be stored only in memory and thus lost after the client is
 //! destroyed.
+//! * `unstable-synapse-quirks`: Enables support to deal with inconsistencies
+//! of Synapse in compliance with the Matrix API specification.
 //! * `socks`: Enables SOCKS support in reqwest, the default HTTP client.
 
 #![deny(
diff --git a/matrix_sdk_base/Cargo.toml b/matrix_sdk_base/Cargo.toml
index e8ab3636..25c868d7 100644
--- a/matrix_sdk_base/Cargo.toml
+++ b/matrix_sdk_base/Cargo.toml
@@ -19,6 +19,7 @@ default = ["encryption", "sqlite_cryptostore", "messages"]
 messages = []
 encryption = ["matrix-sdk-crypto"]
 sqlite_cryptostore = ["matrix-sdk-crypto/sqlite_cryptostore"]
+unstable-synapse-quirks = ["matrix-sdk-common/unstable-synapse-quirks"]
 
 docs = ["encryption", "sqlite_cryptostore", "messages"]
 
diff --git a/matrix_sdk_base/src/lib.rs b/matrix_sdk_base/src/lib.rs
index 5b52ec62..1934faf5 100644
--- a/matrix_sdk_base/src/lib.rs
+++ b/matrix_sdk_base/src/lib.rs
@@ -24,6 +24,8 @@
 //! keys. If this is disabled and `encryption` support is enabled the keys will
 //! by default be stored only in memory and thus lost after the client is
 //! destroyed.
+//! * `unstable-synapse-quirks`: Enables support to deal with inconsistencies
+//! of Synapse in compliance with the Matrix API specification.
 #![deny(
     missing_debug_implementations,
     dead_code,
diff --git a/matrix_sdk_common/Cargo.toml b/matrix_sdk_common/Cargo.toml
index 8cb3e794..181c199d 100644
--- a/matrix_sdk_common/Cargo.toml
+++ b/matrix_sdk_common/Cargo.toml
@@ -10,6 +10,9 @@ readme = "README.md"
 repository = "https://github.com/matrix-org/matrix-rust-sdk"
 version = "0.1.0"
 
+[features]
+unstable-synapse-quirks = ["ruma/unstable-synapse-quirks"]
+
 [dependencies]
 assign = "1.1.0"
 instant = { version = "0.1.6", features = ["wasm-bindgen", "now"] }