diff --git a/eppo_core/src/configuration.rs b/eppo_core/src/configuration.rs
index f8a6c3c3..72eef8bf 100644
--- a/eppo_core/src/configuration.rs
+++ b/eppo_core/src/configuration.rs
@@ -12,7 +12,8 @@ pub struct Configuration {
     pub flags: Option<UniversalFlagConfig>,
     /// Bandits configuration.
     pub bandits: Option<BanditResponse>,
-    /// Mapping from flag key to flag variation value to bandit variation.
+    /// Mapping from flag key to flag variation value to bandit variation. Cached from
+    /// `self.flags.bandits`.
     pub flag_to_bandit_associations:
         HashMap</* flag_key: */ String, HashMap</* variation_key: */ String, BanditVariation>>,
 }
diff --git a/eppo_core/src/configuration_store.rs b/eppo_core/src/configuration_store.rs
index 2e105437..d32f5f71 100644
--- a/eppo_core/src/configuration_store.rs
+++ b/eppo_core/src/configuration_store.rs
@@ -46,8 +46,13 @@ impl ConfigurationStore {
 mod tests {
     use std::{collections::HashMap, sync::Arc};
 
+    use chrono::Utc;
+
     use super::ConfigurationStore;
-    use crate::{ufc::UniversalFlagConfig, Configuration};
+    use crate::{
+        ufc::{Environment, UniversalFlagConfig},
+        Configuration,
+    };
 
     #[test]
     fn can_set_configuration_from_another_thread() {
@@ -58,6 +63,10 @@ mod tests {
             let _ = std::thread::spawn(move || {
                 store.set_configuration(Configuration::new(
                     Some(UniversalFlagConfig {
+                        created_at: Utc::now(),
+                        environment: Environment {
+                            name: "test".to_owned(),
+                        },
                         flags: HashMap::new(),
                         bandits: HashMap::new(),
                     }),
diff --git a/eppo_core/src/ufc/models.rs b/eppo_core/src/ufc/models.rs
index 7280dedd..0fea4260 100644
--- a/eppo_core/src/ufc/models.rs
+++ b/eppo_core/src/ufc/models.rs
@@ -12,6 +12,10 @@ pub type Timestamp = chrono::DateTime<chrono::Utc>;
 #[derive(Debug, Serialize, Deserialize, Clone)]
 #[serde(rename_all = "camelCase")]
 pub struct UniversalFlagConfig {
+    /// When configuration was last updated.
+    pub created_at: Timestamp,
+    /// Environment this configuration belongs to.
+    pub environment: Environment,
     /// Flags configuration.
     ///
     /// Value is wrapped in `TryParse` so that if we fail to parse one flag (e.g., new server
@@ -23,6 +27,13 @@ pub struct UniversalFlagConfig {
     pub bandits: HashMap<String, Vec<BanditVariation>>,
 }
 
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Environment {
+    /// Name of the environment.
+    pub name: String,
+}
+
 /// `TryParse` allows the subfield to fail parsing without failing the parsing of the whole
 /// structure.
 ///
@@ -314,6 +325,8 @@ mod tests {
         let ufc: UniversalFlagConfig = serde_json::from_str(
             &r#"
               {
+                "createdAt": "2024-07-18T00:00:00Z",
+                "environment": {"name": "test"},
                 "flags": {
                   "success": {
                     "key": "success",
diff --git a/rust-sdk/Cargo.toml b/rust-sdk/Cargo.toml
index 6acfbc18..a21536ff 100644
--- a/rust-sdk/Cargo.toml
+++ b/rust-sdk/Cargo.toml
@@ -19,4 +19,5 @@ serde_json = "1.0.116"
 name = "simple"
 
 [dev-dependencies]
+chrono = "0.4.38"
 env_logger = { version = "0.11.3", features = ["unstable-kv"] }
diff --git a/rust-sdk/src/client.rs b/rust-sdk/src/client.rs
index b322b0fe..142c37be 100644
--- a/rust-sdk/src/client.rs
+++ b/rust-sdk/src/client.rs
@@ -362,7 +362,10 @@ mod tests {
     use crate::{client::AssignmentValue, Client, ClientConfig};
     use eppo_core::{
         configuration_store::ConfigurationStore,
-        ufc::{Allocation, Flag, Split, TryParse, UniversalFlagConfig, Variation, VariationType},
+        ufc::{
+            Allocation, Environment, Flag, Split, TryParse, UniversalFlagConfig, Variation,
+            VariationType,
+        },
         Configuration,
     };
 
@@ -393,6 +396,10 @@ mod tests {
         // updating configuration after client is created
         configuration_store.set_configuration(Configuration::new(
             Some(UniversalFlagConfig {
+                created_at: chrono::Utc::now(),
+                environment: Environment {
+                    name: "test".to_owned(),
+                },
                 flags: [(
                     "flag".to_owned(),
                     TryParse::Parsed(Flag {