diff --git a/src/steps/generic.rs b/src/steps/generic.rs
index a24cd167..7abf6c9d 100644
--- a/src/steps/generic.rs
+++ b/src/steps/generic.rs
@@ -89,17 +89,7 @@ pub fn run_rubygems(base_dirs: &BaseDirs, run_type: RunType) -> Result<()> {
 
     print_separator("RubyGems");
 
-    let mut command = run_type.execute(gem);
-    command.args(["update", "--system"]);
-
-    if env::var_os("RBENV_SHELL").is_none() {
-        debug!("Did not detect rbenv. Adding --user-install");
-        command.arg("--user-install");
-    } else {
-        debug!("Detected rbenv. Avoiding --user-install");
-    }
-
-    command.status_checked()
+    run_type.execute(gem).args(["update", "--system"]).status_checked()
 }
 
 pub fn run_haxelib_update(ctx: &ExecutionContext) -> Result<()> {