diff --git a/Cargo.lock b/Cargo.lock
index 2e96bf2..2d0b65a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1156,6 +1156,7 @@ dependencies = [
  "caps",
  "nix",
  "once_cell",
+ "rustc_version",
  "uzers",
 ]
 
@@ -1165,6 +1166,15 @@ version = "0.1.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d626bb9dae77e28219937af045c257c28bfd3f69333c512553507f5f9798cb76"
 
+[[package]]
+name = "rustc_version"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bfa0f585226d2e68097d4f95d113b15b83a82e819ab25717ec0590d9584ef366"
+dependencies = [
+ "semver",
+]
+
 [[package]]
 name = "rustix"
 version = "0.38.32"
@@ -1196,6 +1206,12 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "semver"
+version = "1.0.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "92d43fe69e652f3df9bdc2b85b2854a0825b86e4fb76bc44d945137d053639ca"
+
 [[package]]
 name = "serde"
 version = "1.0.197"
diff --git a/crates/rsjudge-runner/Cargo.toml b/crates/rsjudge-runner/Cargo.toml
index a99f0b5..7f52d26 100644
--- a/crates/rsjudge-runner/Cargo.toml
+++ b/crates/rsjudge-runner/Cargo.toml
@@ -13,3 +13,6 @@ caps = "0.5.5"
 nix = { version = "0.28.0", features = ["user"] }
 once_cell = "1.19.0"
 uzers = "0.11.3"
+
+[build-dependencies]
+rustc_version = "0.4.0"
diff --git a/crates/rsjudge-runner/src/lib.rs b/crates/rsjudge-runner/src/lib.rs
index 9a50c91..b92c4b9 100644
--- a/crates/rsjudge-runner/src/lib.rs
+++ b/crates/rsjudge-runner/src/lib.rs
@@ -15,23 +15,38 @@ impl RunAs for Command {
 
         self.uid(uid).gid(gid);
 
-        let groups: Vec<_> = user
-            .groups()
-            .unwrap_or_default()
-            .into_iter()
-            .map(|g| Gid::from_raw(g.gid()))
-            .collect();
-
         // SAFETY: `group` is moved into the closure,
         // and no longer accessible outside it.
         //
         // Replace with `CommandExt::groups` once it's stable.
-        unsafe {
-            self.pre_exec(move || {
-                setgroups(&groups)?;
-                Ok(())
-            })
-        };
+        #[cfg(not(setgroups))]
+        {
+            let groups: Vec<_> = user
+                .groups()
+                .unwrap_or_default()
+                .into_iter()
+                .map(|g| Gid::from_raw(g.gid()))
+                .collect();
+            unsafe {
+                self.pre_exec(move || {
+                    setgroups(&groups)?;
+                    Ok(())
+                })
+            };
+        }
+
+        #[cfg(setgroups)]
+        {
+            let groups: Vec<_> = user
+                .groups()
+                .unwrap_or_default()
+                .into_iter()
+                .map(|g| g.gid())
+                .collect();
+
+            self.groups(groups);
+        }
+
         self
     }
 }