diff --git a/src/build/opcode/environment.rs b/src/build/opcode/environment.rs
new file mode 100644
index 0000000..de4a8de
--- /dev/null
+++ b/src/build/opcode/environment.rs
@@ -0,0 +1,48 @@
+// Copyright 2019 Jeremy Wall
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+use std::collections::BTreeMap;
+use std::io::Write;
+use std::rc::Rc;
+
+use super::cache;
+use super::Value;
+use crate::convert::{ConverterRegistry, ImporterRegistry};
+
+// Shared Environmental between VM's for runtime usage.
+pub struct Environment<Stdout, Stderr>
+where
+    Stdout: Write,
+    Stderr: Write,
+{
+    pub val_cache: BTreeMap<String, Rc<Value>>,
+    pub op_cache: cache::Ops,                  // Shared environment
+    pub converter_registry: ConverterRegistry, // Shared environment
+    pub importer_registry: ImporterRegistry,   // Shared environment
+    pub stdout: Stdout,                        // Shared environment
+    pub stderr: Stderr,                        // Shared environment
+                                               // TODO(jwall): Environment Variables
+}
+
+impl<Stdout: Write, Stderr: Write> Environment<Stdout, Stderr> {
+    pub fn new(out: Stdout, err: Stderr) -> Self {
+        Self {
+            val_cache: BTreeMap::new(),
+            op_cache: cache::Ops::new(),
+            converter_registry: ConverterRegistry::make_registry(),
+            importer_registry: ImporterRegistry::make_registry(),
+            stdout: out,
+            stderr: err,
+        }
+    }
+}
diff --git a/src/build/opcode/mod.rs b/src/build/opcode/mod.rs
index 2981be4..6618549 100644
--- a/src/build/opcode/mod.rs
+++ b/src/build/opcode/mod.rs
@@ -15,6 +15,7 @@ use std::convert::{TryFrom, TryInto};
 use std::rc::Rc;
 
 mod cache;
+mod environment;
 mod error;
 pub mod pointer;
 mod runtime;
diff --git a/src/build/opcode/runtime.rs b/src/build/opcode/runtime.rs
index 1646195..4f14f1f 100644
--- a/src/build/opcode/runtime.rs
+++ b/src/build/opcode/runtime.rs
@@ -11,87 +11,75 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-use std::collections::BTreeMap;
-use std::convert::TryFrom;
-use std::convert::TryInto;
+use std::cell::RefCell;
+use std::convert::{TryFrom, TryInto};
 use std::fs::File;
-use std::io::{Read, Write};
+use std::io::Read;
 use std::path::{Path, PathBuf};
 use std::rc::Rc;
 
 use regex::Regex;
 
-use super::cache;
+use super::environment::Environment;
 use super::Value::{C, F, P};
 use super::VM;
 use super::{Composite, Error, Hook, Primitive, Value};
 use crate::ast::Position;
 use crate::build::ir::Val;
 use crate::build::AssertCollector;
-use crate::convert::{ConverterRegistry, ImporterRegistry};
 use Composite::{List, Tuple};
 use Primitive::{Bool, Empty, Int, Str};
 
-pub struct Builtins<Out: Write, Err: Write> {
-    op_cache: cache::Ops,
-    val_cache: BTreeMap<String, Rc<Value>>,
+pub struct Builtins {
     assert_results: AssertCollector,
-    converter_registry: ConverterRegistry,
-    importer_registry: ImporterRegistry,
     working_dir: PathBuf,
     import_path: Vec<PathBuf>,
-    stdout: Out,
-    stderr: Err,
 }
 
-type ByteSink = Vec<u8>;
-
-impl<Out: Write, Err: Write> Builtins<Out, Err> {
-    pub fn new(out: Out, err: Err) -> Self {
-        Self::with_working_dir(std::env::current_dir().unwrap(), out, err)
+impl Builtins {
+    pub fn new() -> Self {
+        Self::with_working_dir(std::env::current_dir().unwrap())
     }
 
-    pub fn with_working_dir<P: Into<PathBuf>>(path: P, out: Out, err: Err) -> Self {
+    pub fn with_working_dir<P: Into<PathBuf>>(path: P) -> Self {
         Self {
-            op_cache: cache::Ops::new(),
-            val_cache: BTreeMap::new(),
             assert_results: AssertCollector::new(),
-            converter_registry: ConverterRegistry::make_registry(),
-            importer_registry: ImporterRegistry::make_registry(),
-            // FIXME(jwall): This should move into the VM and not in the Runtime.
             working_dir: path.into(),
             import_path: Vec::new(),
-            stdout: out,
-            stderr: err,
         }
     }
 
-    pub fn get_stdout(&self) -> &Out {
-        &self.stdout
+    pub fn clone(&self) -> Self {
+        Self {
+            assert_results: AssertCollector::new(),
+            working_dir: self.working_dir.clone(),
+            import_path: self.import_path.clone(),
+        }
     }
 
-    pub fn get_stderr(&self) -> &Err {
-        &self.stderr
-    }
-
-    pub fn handle<P: AsRef<Path>>(
+    pub fn handle<P: AsRef<Path>, O, E>(
         &mut self,
         path: P,
         h: Hook,
         stack: &mut Vec<Rc<Value>>,
-    ) -> Result<(), Error> {
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         match h {
-            Hook::Import => self.import(stack),
-            Hook::Include => self.include(stack),
+            Hook::Import => self.import(stack, env),
+            Hook::Include => self.include(stack, env),
             Hook::Assert => self.assert(stack),
-            Hook::Convert => self.convert(stack),
-            Hook::Out => self.out(path, stack),
-            Hook::Map => self.map(path, stack),
-            Hook::Filter => self.filter(path, stack),
-            Hook::Reduce => self.reduce(path, stack),
+            Hook::Convert => self.convert(stack, env),
+            Hook::Out => self.out(path, stack, env),
+            Hook::Map => self.map(path, stack, env),
+            Hook::Filter => self.filter(path, stack, env),
+            Hook::Reduce => self.reduce(path, stack, env),
             Hook::Regex => self.regex(stack),
             Hook::Range => self.range(stack),
-            Hook::Trace(pos) => self.trace(stack, pos),
+            Hook::Trace(pos) => self.trace(stack, pos, env),
         }
     }
 
@@ -142,21 +130,35 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         Ok(contents)
     }
 
-    fn import(&mut self, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn import<O, E>(
+        &mut self,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         let path = stack.pop();
         if let Some(val) = path {
             if let &Value::P(Str(ref path)) = val.as_ref() {
-                if self.val_cache.contains_key(path) {
-                    stack.push(self.val_cache[path].clone());
+                let mut borrowed_env = env.borrow_mut();
+                let val_cache = &mut borrowed_env.val_cache;
+                if val_cache.contains_key(path) {
+                    stack.push(val_cache[path].clone());
                 } else {
-                    let op_pointer = self.op_cache.entry(path).get_pointer_or_else(|| {
-                        // FIXME(jwall): import
-                        unimplemented!("Compiling paths are not implemented yet");
-                    });
-                    let mut vm = VM::with_pointer(path, op_pointer);
+                    let op_pointer =
+                        env.borrow_mut()
+                            .op_cache
+                            .entry(path)
+                            .get_pointer_or_else(|| {
+                                // FIXME(jwall): import
+                                unimplemented!("Compiling paths are not implemented yet");
+                            });
+                    let mut vm = VM::with_pointer(path, op_pointer, env.clone());
                     vm.run()?;
                     let result = Rc::new(vm.symbols_to_tuple(true));
-                    self.val_cache.insert(path.clone(), result.clone());
+                    val_cache.insert(path.clone(), result.clone());
                     stack.push(result);
                 }
                 return Ok(());
@@ -165,7 +167,15 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         return Err(dbg!(Error {}));
     }
 
-    fn include(&self, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn include<O, E>(
+        &self,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         // TODO(jwall): include
         let path = stack.pop();
         let typ = stack.pop();
@@ -190,21 +200,23 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         if typ == "str" {
             stack.push(Rc::new(P(Str(self.get_file_as_string(&path)?))));
         } else {
-            stack.push(Rc::new(match self.importer_registry.get_importer(&typ) {
-                Some(importer) => {
-                    let contents = self.get_file_as_string(&path)?;
-                    if contents.len() == 0 {
-                        eprintln!("including an empty file. Use NULL as the result");
-                        P(Empty)
-                    } else {
-                        match importer.import(contents.as_bytes()) {
-                            Ok(v) => v.try_into()?,
-                            Err(_e) => return Err(dbg!(Error {})),
+            stack.push(Rc::new(
+                match env.borrow().importer_registry.get_importer(&typ) {
+                    Some(importer) => {
+                        let contents = self.get_file_as_string(&path)?;
+                        if contents.len() == 0 {
+                            eprintln!("including an empty file. Use NULL as the result");
+                            P(Empty)
+                        } else {
+                            match importer.import(contents.as_bytes()) {
+                                Ok(v) => v.try_into()?,
+                                Err(_e) => return Err(dbg!(Error {})),
+                            }
                         }
                     }
-                }
-                None => return Err(dbg!(Error {})),
-            }));
+                    None => return Err(dbg!(Error {})),
+                },
+            ));
         }
         return Err(dbg!(Error {}));
     }
@@ -243,13 +255,22 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         return Ok(());
     }
 
-    fn out<P: AsRef<Path>>(&self, path: P, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn out<P: AsRef<Path>, O, E>(
+        &self,
+        path: P,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         let val = stack.pop();
         if let Some(val) = val {
             let val = val.try_into()?;
             if let Some(c_type_val) = stack.pop() {
                 if let &Value::S(ref c_type) = c_type_val.as_ref() {
-                    if let Some(c) = self.converter_registry.get_converter(c_type) {
+                    if let Some(c) = env.borrow().converter_registry.get_converter(c_type) {
                         match c.convert(Rc::new(val), &mut File::create(path)?) {
                             Ok(_) => {
                                 // noop
@@ -264,13 +285,21 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         return Err(dbg!(Error {}));
     }
 
-    fn convert(&self, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn convert<O, E>(
+        &self,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         let val = stack.pop();
         if let Some(val) = val {
             let val = val.try_into()?;
             if let Some(c_type_val) = stack.pop() {
                 if let &Value::S(ref c_type) = c_type_val.as_ref() {
-                    if let Some(c) = self.converter_registry.get_converter(c_type) {
+                    if let Some(c) = env.borrow().converter_registry.get_converter(c_type) {
                         let mut buf: Vec<u8> = Vec::new();
                         match c.convert(Rc::new(val), &mut buf) {
                             Ok(_) => {
@@ -289,7 +318,16 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         return Err(dbg!(Error {}));
     }
 
-    fn map<P: AsRef<Path>>(&self, path: P, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn map<P: AsRef<Path>, O, E>(
+        &self,
+        path: P,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         // get the list from the stack
         let list = if let Some(list) = stack.pop() {
             list
@@ -326,13 +364,27 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
             // push function argument on the stack.
             stack.push(e.clone());
             // call function and push it's result on the stack.
-            result_elems.push(VM::fcall_impl(path.as_ref().to_owned(), f, stack)?);
+            result_elems.push(VM::fcall_impl(
+                path.as_ref().to_owned(),
+                f,
+                stack,
+                env.clone(),
+            )?);
         }
         stack.push(Rc::new(C(List(result_elems))));
         Ok(())
     }
 
-    fn filter<P: AsRef<Path>>(&self, path: P, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn filter<P: AsRef<Path>, O, E>(
+        &self,
+        path: P,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         // get the list from the stack
         let list = if let Some(list) = stack.pop() {
             list
@@ -369,7 +421,7 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
             // push function argument on the stack.
             stack.push(e.clone());
             // call function and push it's result on the stack.
-            let condition = VM::fcall_impl(path.as_ref().to_owned(), f, stack)?;
+            let condition = VM::fcall_impl(path.as_ref().to_owned(), f, stack, env.clone())?;
             // Check for empty or boolean results and only push e back in
             // if they are non empty and true
             match condition.as_ref() {
@@ -412,7 +464,16 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         Ok(())
     }
 
-    fn reduce<P: AsRef<Path>>(&self, path: P, stack: &mut Vec<Rc<Value>>) -> Result<(), Error> {
+    fn reduce<P: AsRef<Path>, O, E>(
+        &self,
+        path: P,
+        stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         // get the list from the stack
         let list = if let Some(list) = stack.pop() {
             list
@@ -455,7 +516,7 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
             stack.push(e.clone());
             stack.push(acc.clone());
             // call function and push it's result on the stack.
-            acc = VM::fcall_impl(path.as_ref().to_owned(), f, stack)?;
+            acc = VM::fcall_impl(path.as_ref().to_owned(), f, stack, env.clone())?;
             // Check for empty or boolean results and only push e back in
             // if they are non empty and true
         }
@@ -505,7 +566,16 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         Ok(())
     }
 
-    fn trace(&mut self, mut stack: &mut Vec<Rc<Value>>, pos: Position) -> Result<(), Error> {
+    fn trace<O, E>(
+        &mut self,
+        stack: &mut Vec<Rc<Value>>,
+        pos: Position,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Result<(), Error>
+    where
+        O: std::io::Write,
+        E: std::io::Write,
+    {
         let val = if let Some(val) = dbg!(stack.pop()) {
             val
         } else {
@@ -521,9 +591,11 @@ impl<Out: Write, Err: Write> Builtins<Out, Err> {
         };
         let writable_val: Val = TryFrom::try_from(val.clone())?;
         if let Err(_) = writeln!(
-            &mut self.stderr,
+            &mut env.borrow_mut().stderr,
             "TRACE: {} = {} at {}",
-            expr_pretty, writable_val, pos
+            expr_pretty,
+            writable_val,
+            pos
         ) {
             return Err(dbg!(Error {}));
         };
diff --git a/src/build/opcode/test.rs b/src/build/opcode/test.rs
index 8b00402..73e2abe 100644
--- a/src/build/opcode/test.rs
+++ b/src/build/opcode/test.rs
@@ -11,8 +11,10 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
+use std::cell::RefCell;
 use std::rc::Rc;
 
+use super::environment::Environment;
 use super::scope::Stack;
 use super::Composite::{List, Tuple};
 use super::Op::{
@@ -27,7 +29,8 @@ use super::VM;
 macro_rules! assert_cases {
     (__impl__ $cases:expr) => {
         for case in $cases.drain(0..) {
-            let mut vm = VM::new("foo.ucg", Rc::new(case.0));
+            let env = Rc::new(RefCell::new(Environment::new(Vec::new(), Vec::new())));
+            let mut vm = VM::new("foo.ucg", Rc::new(case.0), env);
             vm.run().unwrap();
             assert_eq!(dbg!(vm.pop()).unwrap(), Rc::new(case.1));
         }
@@ -116,7 +119,8 @@ fn bind_op() {
     )];
 
     for case in cases.drain(0..) {
-        let mut vm = VM::new("bar.ucg", Rc::new(case.0));
+        let env = Rc::new(RefCell::new(Environment::new(Vec::new(), Vec::new())));
+        let mut vm = VM::new("bar.ucg", Rc::new(case.0), env);
         vm.run().unwrap();
         let (name, result) = case.1;
         let v = vm.get_binding(name).unwrap();
@@ -577,7 +581,8 @@ macro_rules! assert_parse_cases {
             // TODO(jwall): preprocessor
             let ops = Rc::new(translate::AST::translate(stmts));
             assert!(ops.len() > 0);
-            let mut vm = VM::new("foo.ucg", ops.clone());
+            let env = Rc::new(RefCell::new(Environment::new(Vec::new(), Vec::new())));
+            let mut vm = VM::new("foo.ucg", ops.clone(), env);
             vm.run().unwrap();
             assert_eq!(vm.pop().unwrap(), Rc::new(case.1));
         }
@@ -760,11 +765,11 @@ fn simple_trace() {
     let stmts = parse(OffsetStrIter::from(dbg!("TRACE 1+1;")), None).unwrap();
     let ops = Rc::new(translate::AST::translate(stmts));
     assert!(ops.len() > 0);
-    let mut vm = VM::new("foo.ucg", ops.clone());
+    let env = Rc::new(RefCell::new(Environment::new(Vec::new(), Vec::new())));
+    let mut vm = VM::new("foo.ucg", ops.clone(), env);
     vm.run().unwrap();
     assert_eq!(vm.pop().unwrap(), Rc::new(P(Int(2))));
-    let runtime = vm.get_runtime();
-    let err_out = runtime.get_stderr();
+    let err_out = &vm.env.borrow().stderr;
     assert_eq!(
         String::from_utf8_lossy(err_out).to_owned(),
         "TRACE: 1 + 1 = 2 at line: 1 column: 1\n"
diff --git a/src/build/opcode/translate.rs b/src/build/opcode/translate.rs
index d4daa15..2372155 100644
--- a/src/build/opcode/translate.rs
+++ b/src/build/opcode/translate.rs
@@ -12,10 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 use crate::ast::{BinaryExprType, Expression, FormatArgs, Statement, Value};
-use crate::ast::{FuncOpDef, Position, TemplatePart};
+use crate::ast::{FuncOpDef, TemplatePart};
 use crate::build::format::{ExpressionTemplate, SimpleTemplate, TemplateParser};
 use crate::build::opcode::Primitive;
-use crate::build::opcode::{Func, Hook, Op};
+use crate::build::opcode::{Hook, Op};
 
 pub struct AST();
 
diff --git a/src/build/opcode/vm.rs b/src/build/opcode/vm.rs
index 2ddf25e..c8bb779 100644
--- a/src/build/opcode/vm.rs
+++ b/src/build/opcode/vm.rs
@@ -11,11 +11,11 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-use std::cell::Ref;
 use std::cell::RefCell;
 use std::path::PathBuf;
 use std::rc::Rc;
 
+use super::environment::Environment;
 use super::pointer::OpPointer;
 use super::runtime;
 use super::scope::Stack;
@@ -26,35 +26,48 @@ use super::Value::{C, F, M, P, S, T};
 use super::{Error, Op, Primitive, Value};
 use super::{Func, Module};
 
-pub struct VM {
+pub struct VM<O, E>
+where
+    O: std::io::Write,
+    E: std::io::Write,
+{
     stack: Vec<Rc<Value>>,
     symbols: Stack,
-    // FIXME(jwall): This should be parameterized.
-    runtime: Rc<RefCell<runtime::Builtins<Vec<u8>, Vec<u8>>>>,
+    runtime: runtime::Builtins,
     ops: OpPointer,
     // TODO(jwall): This should be optional
     path: PathBuf,
+    pub env: Rc<RefCell<Environment<O, E>>>,
 }
 
-impl<'a> VM {
-    pub fn new<P: Into<PathBuf>>(path: P, ops: Rc<Vec<Op>>) -> Self {
-        Self::with_pointer(path, OpPointer::new(ops))
+impl<'a, O, E> VM<O, E>
+where
+    O: std::io::Write,
+    E: std::io::Write,
+{
+    pub fn new<P: Into<PathBuf>>(
+        path: P,
+        ops: Rc<Vec<Op>>,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Self {
+        Self::with_pointer(path, OpPointer::new(ops), env)
     }
 
-    pub fn with_pointer<P: Into<PathBuf>>(path: P, ops: OpPointer) -> Self {
+    pub fn with_pointer<P: Into<PathBuf>>(
+        path: P,
+        ops: OpPointer,
+        env: Rc<RefCell<Environment<O, E>>>,
+    ) -> Self {
         Self {
             stack: Vec::new(),
             symbols: Stack::new(),
-            runtime: Rc::new(RefCell::new(runtime::Builtins::new(Vec::new(), Vec::new()))),
+            runtime: runtime::Builtins::new(),
             ops: ops,
             path: path.into(),
+            env: env,
         }
     }
 
-    pub fn get_runtime(&self) -> Ref<runtime::Builtins<Vec<u8>, Vec<u8>>> {
-        self.runtime.as_ref().borrow()
-    }
-
     pub fn to_scoped(self, symbols: Stack) -> Self {
         Self {
             stack: Vec::new(),
@@ -62,6 +75,7 @@ impl<'a> VM {
             runtime: self.runtime.clone(),
             ops: self.ops.clone(),
             path: self.path.clone(),
+            env: self.env.clone(),
         }
     }
 
@@ -304,6 +318,7 @@ impl<'a> VM {
         path: P,
         f: &Func,
         stack: &mut Vec<Rc<Value>>,
+        env: Rc<RefCell<Environment<O, E>>>,
     ) -> Result<Rc<Value>, Error> {
         let Func {
             ref ptr,
@@ -311,7 +326,7 @@ impl<'a> VM {
             ref snapshot,
         } = f;
         // use the captured scope snapshot for the function.
-        let mut vm = Self::with_pointer(path, ptr.clone()).to_scoped(snapshot.clone());
+        let mut vm = Self::with_pointer(path, ptr.clone(), env).to_scoped(snapshot.clone());
         for nm in bindings.iter() {
             // now put each argument on our scope stack as a binding.
             // TODO(jwall): This should do a better error if there is
@@ -327,7 +342,8 @@ impl<'a> VM {
     fn op_new_scope(&mut self, jp: i32, ptr: OpPointer) -> Result<(), Error> {
         let scope_snapshot = self.symbols.snapshot();
         dbg!(&ptr);
-        let mut vm = Self::with_pointer(&self.path, ptr).to_scoped(scope_snapshot);
+        let mut vm =
+            Self::with_pointer(&self.path, ptr, self.env.clone()).to_scoped(scope_snapshot);
         dbg!(&vm.stack);
         vm.run()?;
         dbg!(&vm.stack);
@@ -339,7 +355,7 @@ impl<'a> VM {
     fn op_fcall(&mut self) -> Result<(), Error> {
         let f = dbg!(self.pop())?;
         if let &F(ref f) = f.as_ref() {
-            let val = Self::fcall_impl(&self.path, f, &mut self.stack)?;
+            let val = Self::fcall_impl(&self.path, f, &mut self.stack, self.env.clone())?;
             self.push(dbg!(val))?;
         }
         Ok(())
@@ -641,7 +657,7 @@ impl<'a> VM {
                 }
                 // FIXME(jwall): We need to populate the pkg key for modules.
                 //self.merge_field_into_tuple(&mut flds, "this".to_owned(), this)?;
-                let mut vm = Self::with_pointer(self.path.clone(), ptr.clone());
+                let mut vm = Self::with_pointer(self.path.clone(), ptr.clone(), self.env.clone());
                 vm.push(Rc::new(S("mod".to_owned())))?;
                 vm.push(Rc::new(C(Tuple(flds))))?;
                 vm.run()?;
@@ -757,8 +773,7 @@ impl<'a> VM {
 
     fn op_runtime(&mut self, h: Hook) -> Result<(), Error> {
         self.runtime
-            .borrow_mut()
-            .handle(&self.path, h, &mut self.stack)
+            .handle(&self.path, h, &mut self.stack, self.env.clone())
     }
 
     fn op_render(&mut self) -> Result<(), Error> {