diff --git a/crates/lb/src/runtime.rs b/crates/lb/src/runtime.rs
index a154a1a..d69939e 100644
--- a/crates/lb/src/runtime.rs
+++ b/crates/lb/src/runtime.rs
@@ -14,6 +14,7 @@ pub type ErrorFn = dyn Fn(&luajit::Error);
 pub struct Builder {
     registry: Registry,
     report_err: Rc<ErrorFn>,
+    jit_opts: Vec<String>,
     prohibit_globals: bool,
 }
 
@@ -25,6 +26,14 @@ impl Builder {
                 Some(trace) => eprintln!("unhandled lua error: {err}\n{trace}"),
                 None => eprintln!("unhandled lua error: {err}"),
             }),
+            jit_opts: vec![
+                // more aggressive jit options based on OpenResty's defaults
+                // https://github.com/openresty/luajit2#updated-jit-default-parameters
+                "maxtrace=8000".into(),
+                "maxrecord=16000".into(),
+                "minstitch=3".into(),
+                "maxmcode=40960".into(),
+            ],
             prohibit_globals: false,
         }
     }
@@ -43,6 +52,18 @@ impl Builder {
         self
     }
 
+    pub fn jit_opt(&mut self, opt: impl AsRef<str>) -> &mut Self {
+        self.jit_opts.push(opt.as_ref().into());
+        self
+    }
+
+    pub fn jit_opts(&mut self, opts: impl IntoIterator<Item: AsRef<str>>) -> &mut Self {
+        for opt in opts {
+            self.jit_opt(opt);
+        }
+        self
+    }
+
     pub fn module<T: Module>(&mut self) -> &mut Self {
         self.registry.preload::<T>();
         self
@@ -54,21 +75,11 @@ impl Builder {
         state.eval(&chunk, 0, Some(0))?;
 
         if self.prohibit_globals {
-            let mut s = state.guard();
-            s.eval(
-                &Chunk::new(luaify_chunk!({
-                    return |self, key, value| {
-                        error(("undeclared local variable '%s'").format(key), 2);
-                    };
-                })),
-                0,
-                Some(1),
-            )
-            .unwrap();
-            s.push(NewTable::new());
-            (s.push("__index"), s.push_idx(-3), s.set(-3));
-            (s.push("__newindex"), s.push_idx(-3), s.set(-3));
-            s.set_metatable(Index::globals());
+            state_prohibit_globals(&mut state)?;
+        }
+
+        for opt in self.jit_opts.iter() {
+            state_set_jitopt(&mut state, opt)?;
         }
 
         Ok(Runtime {
@@ -81,6 +92,60 @@ impl Builder {
     }
 }
 
+fn state_prohibit_globals(state: &mut State) -> luajit::Result<()> {
+    let mut s = state.guard();
+    let chunk = Chunk::new(luaify_chunk!({
+        return |self, key, value| {
+            error(("undeclared local variable '%s'").format(key), 2);
+        };
+    }))
+    .with_path("[luby]");
+    s.eval(&chunk, 0, Some(1)).unwrap();
+    s.push(NewTable::new());
+    (s.push("__index"), s.push_idx(-3), s.set(-3));
+    (s.push("__newindex"), s.push_idx(-3), s.set(-3));
+    s.set_metatable(Index::globals());
+    Ok(())
+}
+
+fn state_set_jitopt(state: &mut State, opt: &str) -> luajit::Result<()> {
+    let mut s = state.guard();
+    if let Some((cmd, opt)) = parse_jitlib_cmd(opt)
+        && let Ok(_) = s.require(format!("jit.{cmd}"), Some(1))
+    {
+        // require("jit.{cmd}").start(opt)
+        (s.push("start"), s.get(-2));
+        s.push(opt);
+        s.call(1, Some(0))?;
+    } else {
+        s.require("jit", Some(1)).unwrap();
+        match opt {
+            cmd @ ("on" | "off" | "flush") => {
+                // require("jit").<on|off|flush>()
+                (s.push(cmd), s.get(-2));
+                s.call(0, Some(0))?;
+            }
+            _ => {
+                // require("jit").opt.start(opt)
+                (s.push("opt"), s.get(-2));
+                (s.push("start"), s.get(-2));
+                s.push(opt);
+                s.call(1, Some(0))?;
+            }
+        }
+    }
+    Ok(())
+}
+
+fn parse_jitlib_cmd(cmd: &str) -> Option<(&str, &str)> {
+    match cmd {
+        "p" => Some(("p", "Flspv10")),    // default -jp flags
+        "v" => Some(("v", "-")),          // default -jv flags
+        "dump" => Some(("dump", "tirs")), // default -jdump flags
+        _ => cmd.split_once('='),
+    }
+}
+
 #[derive(Deref, DerefMut)]
 pub struct Runtime {
     #[deref]
diff --git a/src/main.rs b/src/main.rs
index 85d2ad1..263f148 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -231,60 +231,18 @@ fn init_tokio(args: &Args) -> tokio::runtime::Runtime {
 }
 
 fn init_lua(args: &Args) -> lb::runtime::Runtime {
-    let mut rt = {
-        let mut rt = lb::runtime::Builder::new();
-        luby::open(&mut rt);
+    let mut rt = lb::runtime::Builder::new();
+    luby::open(&mut rt);
 
-        if args.dump.iter().find(|s| *s == "cdef").is_some() {
-            print!("{}", rt.registry()); // for cdef debugging
-        }
-
-        rt.unhandled_error(error_cb)
-            .prohibit_globals(!args.allow_globals)
-            .build()
-            .unwrap()
-    };
-
-    for arg in args.jit.iter() {
-        let mut s = rt.guard();
-        let res = if let Some((cmd, flags)) = parse_jitlib_cmd(arg)
-            && let Ok(_) = s.require(format!("jit.{cmd}"), Some(1))
-        {
-            (s.push("start"), s.get(-2));
-            s.push(flags);
-            s.call(1, Some(0)) // require("jit.{cmd}").start(flags)
-        } else {
-            s.require("jit", Some(1)).unwrap();
-            match arg.as_str() {
-                cmd @ ("on" | "off" | "flush") => {
-                    (s.push(cmd), s.get(-2));
-                    s.call(0, Some(0)) // require("jit").[on/off/flush]()
-                }
-                flags => {
-                    (s.push("opt"), s.get(-2));
-                    (s.push("start"), s.get(-2));
-                    s.push(flags);
-                    s.call(1, Some(0)) // require("jit").opt.start(flags)
-                }
-            }
-        };
-
-        if let Err(err) = res {
-            drop(s);
-            rt.report_error(&err);
-        }
+    if args.dump.iter().find(|s| *s == "cdef").is_some() {
+        print!("{}", rt.registry()); // for cdef debugging
     }
 
-    rt
-}
-
-fn parse_jitlib_cmd(s: &str) -> Option<(&str, &str)> {
-    match s {
-        "p" => Some(("p", "Flspv10")),    // default -jp flags
-        "v" => Some(("v", "-")),          // default -jv flags
-        "dump" => Some(("dump", "tirs")), // default -jdump flags
-        _ => s.split_once('='),
-    }
+    rt.unhandled_error(error_cb)
+        .prohibit_globals(!args.allow_globals)
+        .jit_opts(args.jit.iter())
+        .build()
+        .unwrap()
 }
 
 async fn main_async(args: Args, cx: &mut lb::runtime::Context) -> ExitCode {