diff --git a/core/Cargo.toml b/core/Cargo.toml
index c436be1f1303..4477c84bb30d 100644
--- a/core/Cargo.toml
+++ b/core/Cargo.toml
@@ -275,7 +275,7 @@ sqlx = { version = "0.8.0", features = [
 ], optional = true }
 
 # For http based services.
-reqsign = { version = "0.16", default-features = false, optional = true }
+reqsign = { version = "0.16.1", default-features = false, optional = true }
 
 # for services-atomic-server
 atomic_lib = { version = "0.39.0", optional = true }
diff --git a/core/src/services/s3/backend.rs b/core/src/services/s3/backend.rs
index 43f266e7c6a4..4c9d6b5973f3 100644
--- a/core/src/services/s3/backend.rs
+++ b/core/src/services/s3/backend.rs
@@ -668,7 +668,7 @@ impl Builder for S3Builder {
     const SCHEME: Scheme = Scheme::S3;
     type Config = S3Config;
 
-    fn build(self) -> Result<impl Access> {
+    fn build(mut self) -> Result<impl Access> {
         debug!("backend build started: {:?}", &self);
 
         let root = normalize_root(&self.config.root.clone().unwrap_or_default());
@@ -753,9 +753,10 @@ impl Builder for S3Builder {
             }
         }
 
-        if let Some(v) = self.config.region.clone() {
-            cfg.region = Some(v);
+        if let Some(ref v) = self.config.region {
+            cfg.region = Some(v.to_string());
         }
+
         if cfg.region.is_none() {
             return Err(Error::new(
                 ErrorKind::ConfigInvalid,
@@ -768,6 +769,9 @@ impl Builder for S3Builder {
         let region = cfg.region.to_owned().unwrap();
         debug!("backend use region: {region}");
 
+        // Retain the user's endpoint if it exists; otherwise, try loading it from the environment.
+        self.config.endpoint = self.config.endpoint.or_else(|| cfg.endpoint_url.clone());
+
         // Building endpoint.
         let endpoint = self.build_endpoint(&region);
         debug!("backend use endpoint: {endpoint}");
diff --git a/core/src/services/s3/config.rs b/core/src/services/s3/config.rs
index 291706f5c16b..b1b31d5bbc72 100644
--- a/core/src/services/s3/config.rs
+++ b/core/src/services/s3/config.rs
@@ -51,7 +51,9 @@ pub struct S3Config {
     /// If user inputs endpoint without scheme like "s3.amazonaws.com", we
     /// will prepend "https://" before it.
     ///
-    /// default to `https://s3.amazonaws.com` if not set.
+    /// - If endpoint is set, we will take user's input first.
+    /// - If not, we will try to load it from environment.
+    /// - If still not set, default to `https://s3.amazonaws.com`.
     pub endpoint: Option<String>,
     /// Region represent the signing region of this endpoint. This is required
     /// if you are using the default AWS S3 endpoint.