diff --git a/src/database.rs b/src/database.rs
index 6bb1b17..06a708d 100644
--- a/src/database.rs
+++ b/src/database.rs
@@ -123,6 +123,7 @@ impl Database {
                 userid_avatarurl: db.open_tree("userid_avatarurl")?,
                 userdeviceid_token: db.open_tree("userdeviceid_token")?,
                 userdeviceid_metadata: db.open_tree("userdeviceid_metadata")?,
+                userid_devicelistversion: db.open_tree("userid_devicelistversion")?,
                 token_userdeviceid: db.open_tree("token_userdeviceid")?,
                 onetimekeyid_onetimekeys: db.open_tree("onetimekeyid_onetimekeys")?,
                 userid_lastonetimekeyupdate: db.open_tree("userid_lastonetimekeyupdate")?,
diff --git a/src/database/users.rs b/src/database/users.rs
index c794e52..9cdfb5f 100644
--- a/src/database/users.rs
+++ b/src/database/users.rs
@@ -22,6 +22,7 @@ pub struct Users {
     pub(super) userid_avatarurl: sled::Tree,
     pub(super) userdeviceid_token: sled::Tree,
     pub(super) userdeviceid_metadata: sled::Tree, // This is also used to check if a device exists
+    pub(super) userid_devicelistversion: sled::Tree, // DevicelistVersion = u64
     pub(super) token_userdeviceid: sled::Tree,
 
     pub(super) onetimekeyid_onetimekeys: sled::Tree, // OneTimeKeyId = UserId + DeviceKeyId
@@ -189,6 +190,10 @@ impl Users {
         userdeviceid.push(0xff);
         userdeviceid.extend_from_slice(device_id.as_bytes());
 
+        self.userid_devicelistversion
+            .update_and_fetch(&user_id.as_bytes(), utils::increment)?
+            .expect("utils::increment will always put in a value");
+
         self.userdeviceid_metadata.insert(
             userdeviceid,
             serde_json::to_string(&Device {
@@ -227,6 +232,10 @@ impl Users {
 
         // TODO: Remove onetimekeys
 
+        self.userid_devicelistversion
+            .update_and_fetch(&user_id.as_bytes(), utils::increment)?
+            .expect("utils::increment will always put in a value");
+
         self.userdeviceid_metadata.remove(&userdeviceid)?;
 
         Ok(())
@@ -811,6 +820,10 @@ impl Users {
         // Only existing devices should be able to call this.
         assert!(self.userdeviceid_metadata.get(&userdeviceid)?.is_some());
 
+        self.userid_devicelistversion
+            .update_and_fetch(&user_id.as_bytes(), utils::increment)?
+            .expect("utils::increment will always put in a value");
+
         self.userdeviceid_metadata.insert(
             userdeviceid,
             serde_json::to_string(device)
@@ -840,6 +853,16 @@ impl Users {
             })
     }
 
+    pub fn get_devicelist_version(&self, user_id: &UserId) -> Result<Option<u64>> {
+        self.userid_devicelistversion
+            .get(user_id.as_bytes())?
+            .map_or(Ok(None), |bytes| {
+                utils::u64_from_bytes(&bytes)
+                    .map_err(|_| Error::bad_database("Invalid devicelistversion in db."))
+                    .map(Some)
+            })
+    }
+
     pub fn all_devices_metadata(&self, user_id: &UserId) -> impl Iterator<Item = Result<Device>> {
         let mut key = user_id.as_bytes().to_vec();
         key.push(0xff);
diff --git a/src/main.rs b/src/main.rs
index 3157023..ba8448d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -171,6 +171,7 @@ fn setup_rocket() -> (rocket::Rocket, Config) {
                 server_server::create_join_event_template_route,
                 server_server::create_join_event_route,
                 server_server::create_invite_route,
+                server_server::get_devices_route,
                 server_server::get_room_information_route,
                 server_server::get_profile_information_route,
             ],
diff --git a/src/server_server.rs b/src/server_server.rs
index 5779b90..e969b31 100644
--- a/src/server_server.rs
+++ b/src/server_server.rs
@@ -8,6 +8,7 @@ use ruma::{
     api::{
         client::error::ErrorKind,
         federation::{
+            device::get_devices::{self, v1::UserDevice},
             directory::{get_public_rooms, get_public_rooms_filtered},
             discovery::{
                 get_remote_server_keys, get_server_keys, get_server_version, ServerSigningKeys,
@@ -1979,6 +1980,46 @@ pub async fn create_invite_route<'a>(
     .into())
 }
 
+#[cfg_attr(
+    feature = "conduit_bin",
+    get("/_matrix/federation/v1/user/devices/<_>", data = "<body>")
+)]
+#[tracing::instrument(skip(db, body))]
+pub fn get_devices_route<'a>(
+    db: State<'a, Database>,
+    body: Ruma<get_devices::v1::Request<'_>>,
+) -> ConduitResult<get_devices::v1::Response> {
+    if !db.globals.allow_federation() {
+        return Err(Error::bad_config("Federation is disabled."));
+    }
+
+    Ok(get_devices::v1::Response {
+        user_id: body.user_id.clone(),
+        stream_id: db
+            .users
+            .get_devicelist_version(&body.user_id)?
+            .unwrap_or(0)
+            .try_into()
+            .expect("version will not grow that large"),
+        devices: db
+            .users
+            .all_devices_metadata(&body.user_id)
+            .filter_map(|r| r.ok())
+            .filter_map(|metadata| {
+                Some(UserDevice {
+                    keys: db
+                        .users
+                        .get_device_keys(&body.user_id, &metadata.device_id)
+                        .ok()??,
+                    device_id: metadata.device_id,
+                    device_display_name: metadata.display_name,
+                })
+            })
+            .collect(),
+    }
+    .into())
+}
+
 #[cfg_attr(
     feature = "conduit_bin",
     get("/_matrix/federation/v1/query/directory", data = "<body>")