diff --git a/Cargo.lock b/Cargo.lock
index a59e6f1..9a015a1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -262,6 +262,7 @@ dependencies = [
  "anyhow",
  "matrix",
  "matrix-macros",
+ "os_info",
  "rand",
 ]
 
@@ -341,6 +342,17 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "os_info"
+version = "3.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "006e42d5b888366f1880eda20371fedde764ed2213dc8496f49622fa0c99cd5e"
+dependencies = [
+ "log",
+ "serde",
+ "winapi",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.17"
@@ -481,6 +493,26 @@ dependencies = [
  "syn 2.0.48",
 ]
 
+[[package]]
+name = "serde"
+version = "1.0.197"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fb1c873e1b9b056a4dc4c0c198b24c3ffa059243875552b2bd0933b1aee4ce2"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.197"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7eb0b34b42edc17f6b7cac84a52a1c5f0e1bb2227e997ca9011ea3dd34e8610b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.48",
+]
+
 [[package]]
 name = "smallvec"
 version = "1.13.1"
diff --git a/matrix-bin/src/helper.rs b/matrix-bin/src/helper.rs
index c0ac5ec..95e0848 100644
--- a/matrix-bin/src/helper.rs
+++ b/matrix-bin/src/helper.rs
@@ -274,10 +274,10 @@ impl Completer for MatrixHelper {
         let mut start = 0;
 
         for char in line.chars() {
-            if buf.is_empty() && char.is_alphabetic() {
+            if buf.is_empty() && (char.is_alphabetic() || char == '_') {
                 start = idx;
                 buf.push(char);
-            } else if !buf.is_empty() && char.is_alphanumeric() {
+            } else if !buf.is_empty() && (char.is_alphanumeric() || char == '_') {
                 buf.push(char);
             } else {
                 if idx >= pos {
diff --git a/matrix-stdlib/Cargo.toml b/matrix-stdlib/Cargo.toml
index bdbd2f9..6256cfa 100644
--- a/matrix-stdlib/Cargo.toml
+++ b/matrix-stdlib/Cargo.toml
@@ -9,4 +9,5 @@ edition = "2021"
 anyhow = "1"
 matrix = { path = "../matrix" }
 matrix-macros = { path = "../matrix-macros" }
+os_info = "3"
 rand = "0.8"
diff --git a/matrix-stdlib/src/math.rs b/matrix-stdlib/src/math.rs
index 3226af5..3f33951 100644
--- a/matrix-stdlib/src/math.rs
+++ b/matrix-stdlib/src/math.rs
@@ -100,7 +100,7 @@ fn mat_get_non_zero_pivot_row(
     Ok(())
 }
 
-fn mat_rref(mat: Matrix) -> Result<Matrix> {
+fn mat_rref(mat: Matrix, full_rref: bool) -> Result<Matrix> {
     let mut mat = mat;
     let Some(start) = mat_find_non_zero_col(&mat) else {
         return Ok(mat)
@@ -112,7 +112,8 @@ fn mat_rref(mat: Matrix) -> Result<Matrix> {
         if mat.get(pivot_row, col)?.is_zero() {
             break
         }
-        for row in 0..mat.codomain {
+        let min = if full_rref { 0 } else { col };
+        for row in min..mat.codomain {
             if row == pivot_row { continue; };
             let scale = mat.get(row, col)?;
             mat_gauss_row_operation(row, pivot_row, scale, &mut mat)?;
@@ -127,9 +128,20 @@ fn rref(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     let mat = match value {
         Value::Matrix(m) => m,
         Value::List(l) => Matrix::from_list(l.to_vec()).into(),
-        _ => return error!("trans must be given a matrix")
+        _ => return error!("rref must be given a matrix")
     };
-    Ok(Value::Matrix(mat_rref(mat.into_inner())?.into()))
+    Ok(Value::Matrix(mat_rref(mat.into_inner(), true)?.into()))
+}
+
+#[native_func(1)]
+fn mat_ref(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [value] = unpack_args!(args);
+    let mat = match value {
+        Value::Matrix(m) => m,
+        Value::List(l) => Matrix::from_list(l.to_vec()).into(),
+        _ => return error!("ref must be given a matrix")
+    };
+    Ok(Value::Matrix(mat_rref(mat.into_inner(), false)?.into()))
 }
 
 fn mat_det(mat: Matrix) -> Result<Value> {
@@ -236,7 +248,7 @@ fn inv(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     let mat = mat.into_inner();
     let ident = mat_ident(mat.domain);
     let joined = mat.join_right(&ident)?;
-    let refed = mat_rref(joined)?;
+    let refed = mat_rref(joined, true)?;
     let (new_ident, new_inv) = mat_splith(refed);
 
     if new_ident == ident {
@@ -393,6 +405,17 @@ fn complex(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     }
 }
 
+#[native_func(1)]
+fn mat(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::List(l) => Ok(V::Matrix(Matrix::from_list(l.to_vec()).into())),
+        V::Matrix(m) => Ok(V::Matrix(m)),
+        arg => error!("cannot cast {arg} to mat")
+    }
+}
+
 #[native_func(1)]
 fn numer(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     use Value as V;
@@ -437,6 +460,140 @@ fn im(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     }
 }
 
+#[native_func(1)]
+fn cis(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [value] = unpack_args!(args);
+    match value.promote_trig() {
+        Value::Float(f) => Ok(Value::Complex(Complex64::cis(f))),
+        Value::Complex(c) => Ok((Value::Complex(Complex64::cis(c.re)) *  Value::Float((-c.im).exp()))?),
+        _ => error!("cis can only take floats")
+    }
+}
+
+#[native_func(1)]
+fn is_finite(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(_) | V::Ratio(_) => Ok(V::Bool(true)),
+        V::Float(f) => Ok(V::Bool(f.is_finite())),
+        V::Complex(c) => Ok(V::Bool(c.is_finite())),
+        _ => error!("is_finite can only take a valid number")
+    }
+}
+
+#[native_func(1)]
+fn is_infinite(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(_) | V::Ratio(_) => Ok(V::Bool(false)),
+        V::Float(f) => Ok(V::Bool(f.is_infinite())),
+        V::Complex(c) => Ok(V::Bool(c.is_infinite())),
+        _ => error!("is_infinite can only take a valid number")
+    }
+}
+
+#[native_func(1)]
+fn is_nan(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(_) | V::Ratio(_) => Ok(V::Bool(false)),
+        V::Float(f) => Ok(V::Bool(f.is_nan())),
+        V::Complex(c) => Ok(V::Bool(c.is_nan())),
+        _ => error!("is_nan can only take a valid number")
+    }
+}
+
+#[native_func(1)]
+fn is_normal(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(_) | V::Ratio(_) => Ok(V::Bool(true)),
+        V::Float(f) => Ok(V::Bool(f.is_normal())),
+        V::Complex(c) => Ok(V::Bool(c.is_normal())),
+        _ => error!("is_normal can only take a valid number")
+    }
+}
+
+#[native_func(1)]
+fn is_subnormal(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(_) | V::Ratio(_) => Ok(V::Bool(false)),
+        V::Float(f) => Ok(V::Bool(f.is_subnormal())),
+        _ => error!("is_subnormal can only take subnormal")
+    }
+}
+
+#[native_func(1)]
+fn is_sign_positive(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(i) => Ok(V::Bool(i > 0)),
+        V::Ratio(r) => Ok(V::Bool(*r.numer() > 0)),
+        V::Float(f) => Ok(V::Bool(f.is_sign_positive())),
+        _ => error!("is_sign_positive can only take a real number")
+    }
+}
+
+#[native_func(1)]
+fn is_sign_negative(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(i) => Ok(V::Bool(i < 0)),
+        V::Ratio(r) => Ok(V::Bool(*r.numer() < 0)),
+        V::Float(f) => Ok(V::Bool(f.is_sign_negative())),
+        _ => error!("is_sign_negative can only take a real number")
+    }
+}
+
+#[native_func(1)]
+fn is_zero(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    use Value as V;
+    let [value] = unpack_args!(args);
+    match value {
+        V::Int(i) => Ok(V::Bool(i == 0)),
+        V::Ratio(r) => Ok(V::Bool(*r.numer() == 0 && *r.denom() != 0)),
+        V::Float(f) => Ok(V::Bool(f == 0.0)),
+        V::Complex(c) => Ok(V::Bool(c.re == 0.0 && c.im == 0.0)),
+        _ => error!("is_zero can only take a valid number")
+    }
+}
+
+#[native_func(2)]
+fn mat_joinh(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [l, r] = unpack_args!(args);
+    let (l, r) = match (l, r) {
+        (Value::List(l), Value::List(r)) => (Matrix::from_list(l.to_vec()), Matrix::from_list(r.to_vec())),
+        (Value::List(l), Value::Matrix(r)) => (Matrix::from_list(l.to_vec()), r.into_inner()),
+        (Value::Matrix(l), Value::List(r)) => (l.into_inner(), Matrix::from_list(r.to_vec())),
+        (Value::Matrix(l), Value::Matrix(r)) => (l.into_inner(), r.into_inner()),
+        _ => return error!("mat_joinh takes two matrices")
+    };
+    let mat = l.join_right(&r)?;
+    Ok(Value::Matrix(mat.into()))
+}
+
+#[native_func(2)]
+fn mat_joinv(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [l, r] = unpack_args!(args);
+    let (l, r) = match (l, r) {
+        (Value::List(l), Value::List(r)) => (Matrix::from_list(l.to_vec()), Matrix::from_list(r.to_vec())),
+        (Value::List(l), Value::Matrix(r)) => (Matrix::from_list(l.to_vec()), r.into_inner()),
+        (Value::Matrix(l), Value::List(r)) => (l.into_inner(), Matrix::from_list(r.to_vec())),
+        (Value::Matrix(l), Value::Matrix(r)) => (l.into_inner(), r.into_inner()),
+        _ => return error!("mat_joinv takes two matrices")
+    };
+    let mat = l.join_bottom(&r)?;
+    Ok(Value::Matrix(mat.into()))
+}
+
 mathr!(floor);
 mathr!(ceil);
 mathr!(round);
@@ -465,10 +622,13 @@ trigf!(to_radians, rad);
 
 pub fn load(vm: &mut Vm) {
     vm.load_global_fn(trans(), "trans");
+    vm.load_global_fn(mat_ref(), "ref");
     vm.load_global_fn(rref(), "rref");
     vm.load_global_fn(det(), "det");
     vm.load_global_fn(ident(), "ident");
     vm.load_global_fn(inv(), "inv");
+    vm.load_global_fn(mat_joinh(), "mat_joinh");
+    vm.load_global_fn(mat_joinv(), "mat_joinv");
 
     vm.load_global(Value::Float(PI), "pi");
     vm.load_global(Value::Float(TAU), "tau");
@@ -481,6 +641,7 @@ pub fn load(vm: &mut Vm) {
     vm.load_global_fn(ratio(), "ratio");
     vm.load_global_fn(float(), "float");
     vm.load_global_fn(complex(), "complex");
+    vm.load_global_fn(mat(), "mat");
     vm.load_global_fn(abs(), "abs");
     vm.load_global_fn(sign(), "sign");
     vm.load_global_fn(floor(), "floor");
@@ -510,9 +671,19 @@ pub fn load(vm: &mut Vm) {
     vm.load_global_fn(atanh(), "atanh");
     vm.load_global_fn(deg(), "deg");
     vm.load_global_fn(rad(), "rad");
+    vm.load_global_fn(cis(), "cis");
 
     vm.load_global_fn(denom(), "denom");
     vm.load_global_fn(numer(), "numer");
     vm.load_global_fn(re(), "re");
     vm.load_global_fn(im(), "im");
+
+    vm.load_global_fn(is_finite(), "is_finite");
+    vm.load_global_fn(is_infinite(), "is_infinite");
+    vm.load_global_fn(is_nan(), "is_nan");
+    vm.load_global_fn(is_zero(), "is_zero");
+    vm.load_global_fn(is_normal(), "is_normal");
+    vm.load_global_fn(is_subnormal(), "is_subnormal");
+    vm.load_global_fn(is_sign_negative(), "is_sign_negative");
+    vm.load_global_fn(is_sign_positive(), "is_sign_positive");
 }
diff --git a/matrix-stdlib/src/sys.rs b/matrix-stdlib/src/sys.rs
index e91e635..d30226f 100644
--- a/matrix-stdlib/src/sys.rs
+++ b/matrix-stdlib/src/sys.rs
@@ -1,7 +1,8 @@
-use std::{process::{exit, Command, Stdio}, env, rc::Rc, io::Read};
+use std::{process::{exit, Command, Stdio, Child}, env, rc::Rc, io::{Read, self}, cell::RefCell, fs::{File, self}, os::fd::FromRawFd, sync::OnceLock, path::PathBuf};
 
 use matrix::{vm::Vm, value::{Value, ValueMap}, unpack_args, Result, gc::Gc};
 use matrix_macros::native_func;
+use os_info::Info;
 use crate::{VmArgs, error};
 
 #[native_func(1)]
@@ -35,26 +36,7 @@ fn env(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     }
 }
 
-#[native_func(2)]
-fn exec(_: VmArgs, args: Vec<Value>) -> Result<Value> {
-    let [cmd, args] = unpack_args!(args);
-    let (cmd, args) = match (cmd, args) {
-        (Value::String(s), Value::List(l)) => (s, l.into_inner()),
-        _ => return error!("exec requires a string cmd and string argument list")
-    };
-    let mut sargs = Vec::new();
-    for arg in args {
-        let Value::String(arg) = arg else {
-            return error!("exec requires a string cmd and string argument list")
-        };
-        sargs.push(arg.to_string());
-    };
-    let cmd = Command::new(cmd.to_string())
-        .args(sargs)
-        .stdin(Stdio::piped())
-        .stdout(Stdio::piped())
-        .stderr(Stdio::piped())
-        .spawn();
+fn exec_impl(cmd: io::Result<Child>) -> Result<Value> {
     let mut child = match cmd {
         Ok(c) => c,
         Err(e) => return error!("error executing command: {e}")
@@ -91,9 +73,180 @@ fn exec(_: VmArgs, args: Vec<Value>) -> Result<Value> {
     Ok(Value::Table(res.into()))
 }
 
+#[native_func(2)]
+fn exec(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [cmd, args] = unpack_args!(args);
+    let (cmd, args) = match (cmd, args) {
+        (Value::String(s), Value::List(l)) => (s, l.into_inner()),
+        _ => return error!("exec requires a string cmd and string argument list")
+    };
+    let mut sargs = Vec::new();
+    for arg in args {
+        let Value::String(arg) = arg else {
+            return error!("exec requires a string cmd and string argument list")
+        };
+        sargs.push(arg.to_string());
+    };
+    let cmd = Command::new(cmd.to_string())
+        .args(sargs)
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .stderr(Stdio::piped())
+        .spawn();
+
+    exec_impl(cmd)
+}
+
+#[native_func(1)]
+fn system(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [cmd] = unpack_args!(args);
+    let Value::String(cmd) = cmd else {
+        return error!("system requires a full command argument string")
+    };
+    let sh = String::from("/bin/sh");
+    let args = vec!["-c".to_string(), cmd.to_string()];
+
+    let cmd = Command::new(sh)
+        .args(args)
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .stderr(Stdio::piped())
+        .spawn();
+
+    exec_impl(cmd)
+}
+
+#[native_func(1)]
+fn systemi(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [cmd] = unpack_args!(args);
+    let Value::String(cmd) = cmd else {
+        return error!("systemi requires a full command argument string")
+    };
+    let sh = String::from("/bin/sh");
+    let args = vec!["-c".to_string(), cmd.to_string()];
+
+    let cmd = Command::new(sh)
+        .args(args)
+        .stdin(Stdio::inherit())
+        .stdout(Stdio::inherit())
+        .stderr(Stdio::inherit())
+        .spawn();
+
+    exec_impl(cmd)
+}
+
+fn stdin() -> Value {
+    let f = unsafe { File::from_raw_fd(0) };
+    Value::File(Rc::new(RefCell::new(f)))
+}
+
+fn stdout() -> Value {
+    let f = unsafe { File::from_raw_fd(1) };
+    Value::File(Rc::new(RefCell::new(f)))
+}
+
+fn stderr() -> Value {
+    let f = unsafe { File::from_raw_fd(2) };
+    Value::File(Rc::new(RefCell::new(f)))
+}
+
+const OS_INFO: OnceLock<Info> = OnceLock::new();
+
+#[native_func(0)]
+fn os_type(_: VmArgs, _: Vec<Value>) -> Result<Value> {
+    Ok(Value::String(OS_INFO.get_or_init(|| os_info::get()).os_type().to_string().into()))
+}
+
+#[native_func(0)]
+fn os_version(_: VmArgs, _: Vec<Value>) -> Result<Value> {
+    Ok(Value::String(OS_INFO.get_or_init(|| os_info::get()).version().to_string().into()))
+}
+
+#[native_func(0)]
+fn os_edition(_: VmArgs, _: Vec<Value>) -> Result<Value> {
+    Ok(Value::String(OS_INFO.get_or_init(|| os_info::get()).edition().unwrap_or("Unknown").into()))
+}
+
+#[native_func(0)]
+fn os_bitness(_: VmArgs, _: Vec<Value>) -> Result<Value> {
+    Ok(Value::String(OS_INFO.get_or_init(|| os_info::get()).bitness().to_string().into()))
+}
+
+#[native_func(0)]
+fn os_arch(_: VmArgs, _: Vec<Value>) -> Result<Value> {
+    Ok(Value::String(OS_INFO.get_or_init(|| os_info::get()).architecture().unwrap_or("Unknown").into()))
+}
+
+#[native_func(0)]
+fn cwd(_: VmArgs, _: Vec<Value>) -> Result<Value> {
+    match env::current_dir() {
+        Ok(v) => Ok(Value::String(v.into_os_string().into_string().unwrap_or(String::new()).into())),
+        Err(e) => error!("cant get cwd: {e}")
+    }
+}
+
+#[native_func(1)]
+fn basename(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [value] = unpack_args!(args);
+    let Value::String(value) = value else {
+        return error!("basename requires a string path")
+    };
+    let path = PathBuf::from(value.to_string());
+    match path.file_name() {
+        Some(p) => Ok(Value::String(p.to_str().unwrap().into())),
+        None => Ok(Value::String(value.into()))
+    }
+}
+
+#[native_func(1)]
+fn dirname(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [value] = unpack_args!(args);
+    let Value::String(value) = value else {
+        return error!("basename requires a string path")
+    };
+    let path = PathBuf::from(value.to_string());
+    let parent = match path.parent() {
+        Some(p) => p,
+        None => path.as_path()
+    };
+    let str = parent.as_os_str().to_str().unwrap();
+    match str {
+        "" => Ok(Value::String(".".into())),
+        s => Ok(Value::String(s.into()))
+    }
+}
+
+#[native_func(1)]
+fn realpath(_: VmArgs, args: Vec<Value>) -> Result<Value> {
+    let [value] = unpack_args!(args);
+    let Value::String(value) = value else {
+        return error!("basename requires a string path")
+    };
+    let path = match fs::canonicalize(value.as_ref()) {
+        Ok(p) => p,
+        Err(e) => return error!("could not get realpath: {e}")
+    };
+    Ok(Value::String(path.to_str().unwrap().into()))
+}
+
+
 pub fn load(vm: &mut Vm) {
     vm.load_global_fn(sys_exit(), "exit");
     vm.load_global_fn(argv(), "argv");
     vm.load_global_fn(exec(), "exec");
+    vm.load_global_fn(system(), "system");
+    vm.load_global_fn(systemi(), "systemi");
     vm.load_global_fn(env(), "env");
+    vm.load_global(stdin(), "stdin");
+    vm.load_global(stdout(), "stdout");
+    vm.load_global(stderr(), "stderr");
+    vm.load_global_fn(os_type(), "os_type");
+    vm.load_global_fn(os_version(), "os_version");
+    vm.load_global_fn(os_edition(), "os_edition");
+    vm.load_global_fn(os_bitness(), "os_bitness");
+    vm.load_global_fn(os_arch(), "os_arch");
+    vm.load_global_fn(cwd(), "cwd");
+    vm.load_global_fn(basename(), "basename");
+    vm.load_global_fn(dirname(), "dirname");
+    vm.load_global_fn(realpath(), "realpath");
 }
diff --git a/matrix/src/gc.rs b/matrix/src/gc.rs
index 8fba633..7af020b 100644
--- a/matrix/src/gc.rs
+++ b/matrix/src/gc.rs
@@ -127,13 +127,21 @@ impl<T> Drop for Gc<T> {
 
 impl<T: Debug> Debug for Gc<T> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{:?}", self.deref())
+        if f.alternate() {
+            write!(f, "{:#?}", self.deref())
+        } else {
+            write!(f, "{:?}", self.deref())
+        }
     }
 }
 
 impl<T: Display> Display for Gc<T> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", self.deref())
+        if f.alternate() {
+            write!(f, "{:#}", self.deref())
+        } else {
+            write!(f, "{}", self.deref())
+        }
     }
 }
 
diff --git a/matrix/src/value.rs b/matrix/src/value.rs
index 3ebc48a..f7d5170 100644
--- a/matrix/src/value.rs
+++ b/matrix/src/value.rs
@@ -197,20 +197,10 @@ impl Display for Value {
                 write!(f, "]")?;
             },
             V::Matrix(m) => {
-                write!(f, "\n")?;
-                for row in m.rows() {
-                    write!(f, "  ")?;
-                    for (i, el) in row.into_iter().enumerate() {
-                        if i != 0 {
-                            write!(f, " ")?;
-                        }
-                        if f.alternate() {
-                            write!(f, "{el:#}")?;
-                        } else {
-                            write!(f, "{el}")?;
-                        }
-                    }
-                    write!(f, "\n")?;
+                if f.alternate() {
+                    write!(f, "{m:#}")?;
+                } else {
+                    write!(f, "{m}")?;
                 }
             },
             V::Table(t) => {
@@ -1025,8 +1015,8 @@ impl Matrix {
     }
 
     pub fn join_right(&self, other: &Matrix) -> Result<Self> {
-        if self.domain != other.domain || self.codomain != other.codomain {
-            return error!("matrix dimensions do not match");
+        if self.codomain != other.codomain {
+            return error!("matrix codomain's do not match");
         }
         let mut r1 = self.rows();
         let mut r2 = other.rows();
@@ -1050,16 +1040,16 @@ impl Matrix {
             .reduce(|mut a,b| {a.extend(b); a})
             .unwrap();
 
-        Ok(Matrix::new(self.domain * 2, self.codomain, values))
+        Ok(Matrix::new(self.domain + other.domain, self.codomain, values))
     }
 
     pub fn join_bottom(&self, other: &Matrix) -> Result<Self> {
-        if self.domain != other.domain || self.codomain != other.codomain {
-            return error!("matrix dimensions do not match");
+        if self.domain != other.domain {
+            return error!("matrix domain's do not match");
         }
         let mut values = self.values.clone();
         values.extend(other.values.clone());
-        Ok(Matrix::new(self.domain, self.codomain * 2, values))
+        Ok(Matrix::new(self.domain, self.codomain + other.codomain, values))
     }
 }
 
@@ -1199,3 +1189,35 @@ impl<'a> Iterator for MatrixCols<'a> {
         Some(res)
     }
 }
+
+impl Display for Matrix {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let mut max_cols = vec![0; self.domain];
+        let mut vals: Vec<String> = Vec::with_capacity(self.domain * self.codomain);
+        for row in 0..self.codomain {
+            for col in 0..self.domain {
+                let idx = col + row * self.domain;
+                let el = &self.values[idx];
+                let s = match f.alternate() {
+                    true => format!("{:#}", el),
+                    false => format!("{}", el)
+                };
+                max_cols[col] = max_cols[col].max(s.len());
+                vals.push(s);
+            }
+        }
+
+        write!(f, "\n")?;
+        for row in 0..self.codomain {
+            for col in 0..self.domain {
+                let idx = col + row * self.domain;
+                let s = vals[idx].as_str();
+                let width = max_cols[col];
+                write!(f, " {s:>width$}")?;
+            }
+            write!(f, "\n")?;
+        }
+
+        Ok(())
+    }
+}
diff --git a/matrix/src/vm.rs b/matrix/src/vm.rs
index f98dc72..e511adf 100644
--- a/matrix/src/vm.rs
+++ b/matrix/src/vm.rs
@@ -164,7 +164,7 @@ pub struct Vm {
     stack: Stack<Value>,
     locals: Stack<Value>,
     trystack: Vec<TryScope>,
-    globals: HashMap<u16, Value>,
+    globals: Rc<RefCell<HashMap<u16, Value>>>,
     names: NamesTable,
     global_names: NamesTable,
     interupt: Arc<AtomicUsize>,
@@ -201,7 +201,7 @@ impl Vm {
             stack: Stack::new(),
             locals: Stack::new(),
             trystack: Vec::new(),
-            globals: HashMap::new(),
+            globals: Rc::new(RefCell::new(HashMap::new())),
             names: Rc::new(RefCell::new(Vec::new())),
             global_names: Rc::new(RefCell::new(Vec::new())),
             interupt: Arc::new(AtomicUsize::new(0)),
@@ -211,7 +211,7 @@ impl Vm {
     pub fn load_global(&mut self, value: Value, name: &str) {
         let idx = self.global_names.borrow().len();
         self.global_names.borrow_mut().push(name.into());
-        self.globals.insert(idx as u16, value);
+        self.globals.borrow_mut().insert(idx as u16, value);
     }
 
     pub fn load_global_fn(&mut self, value: Rc<Function>, name: &str) {
@@ -245,6 +245,7 @@ impl Vm {
             I::DiscardLocals(count) => {self.locals.truncate(self.locals.len() - count as usize)},
             I::LoadGlobal(idx) => {
                 let val = self.globals
+                    .borrow_mut()
                     .get(&idx)
                     .unwrap()
                     .clone();
@@ -252,7 +253,7 @@ impl Vm {
             },
             I::StoreGlobal(idx) => {
                 let val = self.pop();
-                self.globals.insert(idx, val);
+                self.globals.borrow_mut().insert(idx, val);
             },
             I::Const(idx) => self.push(frame.body.constants[idx as usize].clone()),
             I::Int(i) => self.push(Value::Int(i as i64)),
@@ -426,6 +427,9 @@ impl Vm {
     }
 
     fn exec_fn(&mut self, frame: &mut StackFrame, fun: Rc<Function>, params: Vec<Value>) -> VmResult<Value> {
+        if self.check_interupt() {
+            return Ok(Value::Nil)
+        }
         let name = fun.name.clone();
         let params_len = params.len();
         match &fun.fun {