diff --git a/src/stl.rs b/src/stl.rs
index 741d7e0..7f3290e 100644
--- a/src/stl.rs
+++ b/src/stl.rs
@@ -59,7 +59,7 @@ pub fn static_stdlib(syms: &mut SymTable) -> Result<(), String> {
 pub fn dynamic_stdlib(env: bool, syms: &mut SymTable) -> Result<(), String> {
     syms.insert("def".to_string(), Symbol {
         name: String::from("define"),
-        args: Args::Lazy(2),
+        args: Args::Infinite,
         conditional_branches: true,
         value: ValueType::Internal(Rc::new( move |ast: &Seg, syms: &mut SymTable| -> Result<Ctr, String> {
             _store_callback(ast, syms, env)
diff --git a/tests/test_vars.rs b/tests/test_vars.rs
index 431ef4c..ce4041f 100644
--- a/tests/test_vars.rs
+++ b/tests/test_vars.rs
@@ -3,7 +3,7 @@ mod var_lib_tests {
     use relish::stdlib::{static_stdlib, dynamic_stdlib};
 
     #[test]
-    fn test_variable_export_and_lookup() {
+    fn test_variable_def_and_lookup() {
         let doc1 = "(def test 1)";
         let doc2 = "(test)";
         let result = "(1)";
@@ -39,4 +39,110 @@ mod var_lib_tests {
             assert!(false);
         }
     }
+
+    #[test]
+    fn test_variable_def_redef_and_lookup() {
+        let doc1 = "(def test 1)";
+        let doc2 = "(def test '2')";
+        let doc3 = "(test)";
+        let result = "('2')";
+
+        let mut syms = SymTable::new();
+        static_stdlib(&mut syms).unwrap();
+        dynamic_stdlib(false, &mut syms).unwrap();
+
+        if let Ok(tree) = lex(&doc1.to_string()) {
+            let eval_result = *eval(&tree, &mut syms).unwrap();
+            if let Ctr::None = eval_result {
+                // pass
+            } else {
+                eprintln!("bad: {eval_result}");
+                assert!(false);
+            }
+        } else {
+            eprintln!("couldn't lex doc1");
+            assert!(false);
+        }
+
+        if let Ok(tree) = lex(&doc2.to_string()) {
+            println!("tree: {tree}");
+            let eval_result = *eval(&tree, &mut syms).unwrap();
+            if let Ctr::None = eval_result {
+                // pass
+            } else {
+                eprintln!("bad: {eval_result}");
+                assert!(false);
+            }
+        } else {
+            eprintln!("couldn't lex doc2");
+            assert!(false);
+        }
+
+        if let Ok(tree) = lex(&doc3.to_string()) {
+            println!("tree: {tree}");
+            let eval_result = *eval(&tree, &mut syms).unwrap();
+            if let Ctr::Seg(ref i) = eval_result {
+                assert_eq!(i.to_string(), result);
+            } else {
+                eprintln!("bad: {eval_result}");
+                assert!(false);
+            }
+        } else {
+            eprintln!("couldn't lex doc3");
+            assert!(false);
+        }
+    }
+
+    #[test]
+    fn test_variable_def_undef_and_lookup_fail() {
+        let doc1 = "(def test 1)";
+        let doc2 = "(def test)";
+        let doc3 = "(test)";
+
+        let mut syms = SymTable::new();
+        static_stdlib(&mut syms).unwrap();
+        dynamic_stdlib(false, &mut syms).unwrap();
+
+        if let Ok(tree) = lex(&doc1.to_string()) {
+            let eval_result = *eval(&tree, &mut syms).unwrap();
+            if let Ctr::None = eval_result {
+                // pass
+            } else {
+                eprintln!("bad: {eval_result}");
+                assert!(false);
+            }
+        } else {
+            eprintln!("couldn't lex doc1");
+            assert!(false);
+        }
+
+        if let Ok(tree) = lex(&doc2.to_string()) {
+            println!("tree: {tree}");
+            let eval_result = *eval(&tree, &mut syms).unwrap();
+            if let Ctr::None = eval_result {
+                // pass
+            } else {
+                eprintln!("bad: {eval_result}");
+                assert!(false);
+            }
+        } else {
+            eprintln!("couldn't lex doc2");
+            assert!(false);
+        }
+
+        if let Ok(tree) = lex(&doc3.to_string()) {
+            println!("tree: {tree}");
+            let eval_result = eval(&tree, &mut syms);
+            if let Err(s) = eval_result {
+                assert_eq!(s.to_string(), "error in call to test: undefined symbol: test".to_string());
+            } else {
+                let res = eval_result.unwrap();
+                eprintln!("shouldn't have suceeded: {res}");
+                assert!(false);
+            }
+        } else {
+            eprintln!("couldn't lex doc3");
+            assert!(false);
+        }
+    }
 }