diff --git a/flake.lock b/flake.lock
index b306085..b17dd36 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,5 +1,26 @@
 {
   "nodes": {
+    "fenix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "rust-analyzer-src": "rust-analyzer-src"
+      },
+      "locked": {
+        "lastModified": 1774682177,
+        "narHash": "sha256-OVbuJnJLlbHE28eRMudjtA6NXz/ifuXSho79gvh6GHY=",
+        "owner": "nix-community",
+        "repo": "fenix",
+        "rev": "e0f515387df77b9fdbaaf81e7f866f0365474c18",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "repo": "fenix",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1773222311,
@@ -18,10 +39,28 @@
     },
     "root": {
       "inputs": {
+        "fenix": "fenix",
         "nixpkgs": "nixpkgs",
         "systems": "systems"
       }
     },
+    "rust-analyzer-src": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1774569884,
+        "narHash": "sha256-E8iWEPzg7OnE0XXXjo75CX7xFauqzJuGZ5wSO9KS8Ek=",
+        "owner": "rust-lang",
+        "repo": "rust-analyzer",
+        "rev": "443ddcddd0c73b07b799d052f5ef3b448c2f3508",
+        "type": "github"
+      },
+      "original": {
+        "owner": "rust-lang",
+        "ref": "nightly",
+        "repo": "rust-analyzer",
+        "type": "github"
+      }
+    },
     "systems": {
       "locked": {
         "lastModified": 1681028828,
diff --git a/flake.nix b/flake.nix
index f52bd4c..30f7a1d 100644
--- a/flake.nix
+++ b/flake.nix
@@ -4,6 +4,11 @@
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
     systems.url = "github:nix-systems/default";
+
+    fenix = {
+      url = "github:nix-community/fenix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
   outputs = {
@@ -29,8 +34,11 @@
           pkgs = mkPkgs system nixpkgs;
         });
   in {
-    overlays.default = self: super: {
-      libclang = super.llvmPackages_21.libclang;
+    overlays = {
+      default = self: super: {
+        libclang = super.llvmPackages_21.libclang;
+      };
+      fenix = inputs.fenix.overlays.default;
     };
 
     devShells = forAllSystems (
@@ -107,6 +115,91 @@
 
             shellHook = postConfigure;
 
+            env = let
+              inherit (llvmPackages) llvm libclang;
+            in {
+              LD_LIBRARY_PATH = builtins.toString (lib.makeLibraryPath buildInputs);
+              LIBCLANG_PATH = "${libclang.lib}/lib";
+
+              RUST_SRC_PATH = "${pkgs.rustPlatform.rustLibSrc}";
+              BINDGEN_EXTRA_CLANG_ARGS = "--sysroot=${pkgs.glibc.dev}";
+
+              # `cargo-llvm-cov` reads these environment variables to find these binaries,
+              # which are needed to run the tests
+              LLVM_COV = "${llvm}/bin/llvm-cov";
+              LLVM_PROFDATA = "${llvm}/bin/llvm-profdata";
+            };
+          };
+
+        nightly = let
+          nixForBindings = pkgs.nixVersions.nix_2_32;
+          inherit (pkgs.rustc) llvmPackages;
+        in
+          pkgs.mkShell rec {
+            name = "nixide";
+            shell = "${pkgs.bash}/bin/bash";
+            strictDeps = true;
+
+            # packages we need at runtime
+            packages = with pkgs; [
+              llvmPackages.lld
+              lldb
+              (pkgs.fenix.complete.withComponents [
+                "cargo"
+                "clippy"
+                "rust-src"
+                "rustc"
+                "rustfmt"
+              ])
+              rust-analyzer-nightly
+
+              # cargo-c
+              # cargo-llvm-cov
+              # cargo-nextest
+            ];
+
+            # packages we need at build time
+            nativeBuildInputs = with pkgs; [
+              pkg-config
+              glibc.dev
+              nixForBindings.dev
+
+              rustPlatform.bindgenHook
+            ];
+
+            # packages we link against
+            buildInputs = with pkgs; [
+              stdenv.cc
+
+              nixForBindings
+            ];
+
+            # bindgen uses clang to generate bindings, but it doesn't know where to
+            # find our stdenv cc's headers, so when it's gcc, we need to tell it.
+            postConfigure = lib.optionalString pkgs.stdenv.cc.isGNU ''
+              #!/usr/bin/env bash
+              # REF: https://github.com/nixops4/nix-bindings-rust/blob/main/bindgen-gcc.sh
+              # Rust bindgen uses Clang to generate bindings, but that means that it can't
+              # find the "system" or compiler headers when the stdenv compiler is GCC.
+              # This script tells it where to find them.
+
+              echo "Extending BINDGEN_EXTRA_CLANG_ARGS with system include paths..." 2>&1
+              BINDGEN_EXTRA_CLANG_ARGS="$${BINDGEN_EXTRA_CLANG_ARGS:-}"
+              export BINDGEN_EXTRA_CLANG_ARGS
+              include_paths=$(
+                echo | $NIX_CC_UNWRAPPED -v -E -x c - 2>&1 \
+                | awk '/#include <...> search starts here:/{flag=1;next} \
+                      /End of search list./{flag=0} \
+                      flag==1 {print $1}'
+              )
+              for path in $include_paths; do
+                echo " - $path" 2>&1
+                BINDGEN_EXTRA_CLANG_ARGS="$BINDGEN_EXTRA_CLANG_ARGS -I$path"
+              done
+            '';
+
+            shellHook = postConfigure;
+
             env = let
               inherit (llvmPackages) llvm libclang;
             in {
diff --git a/nixide/src/expr/evalstate.rs b/nixide/src/expr/evalstate.rs
index b73b74d..4696549 100644
--- a/nixide/src/expr/evalstate.rs
+++ b/nixide/src/expr/evalstate.rs
@@ -82,7 +82,7 @@ impl EvalState {
             );
             value
         })
-        .map(|ptr| Value::from((ptr, self)))
+        .map(|ptr| Value::from((ptr, std::rc::Rc::new(std::cell::RefCell::new(self)))))
     }
 
     /// Allocate a new value.
@@ -96,7 +96,8 @@ impl EvalState {
             sys::nix_alloc_value(ctx.as_ptr(), self.as_ptr())
         })?;
 
-        Ok(Value::from((inner, self)))
+        // Ok(Value::from((inner, self)))
+        todo!()
     }
 }
 
diff --git a/nixide/src/expr/tests.rs b/nixide/src/expr/tests.rs
index 702b44d..9d2df97 100644
--- a/nixide/src/expr/tests.rs
+++ b/nixide/src/expr/tests.rs
@@ -2,7 +2,7 @@ use std::sync::Arc;
 
 use serial_test::serial;
 
-use super::{EvalStateBuilder, ValueType};
+use super::{EvalStateBuilder, Value};
 use crate::Store;
 
 #[test]
@@ -29,8 +29,12 @@ fn test_simple_evaluation() {
         .eval_from_string("1 + 2", "<eval>")
         .expect("Failed to evaluate expression");
 
-    assert_eq!(result.value_type(), ValueType::Int);
-    assert_eq!(result.as_int().expect("Failed to get int value"), 3);
+    assert!(matches!(result, Value::Int(_)));
+    if let Value::Int(value) = result {
+        assert_eq!(value.as_int(), 3);
+    } else {
+        unreachable!();
+    }
 }
 
 #[test]
@@ -46,22 +50,34 @@ fn test_value_types() {
     let int_val = state
         .eval_from_string("42", "<eval>")
         .expect("Failed to evaluate int");
-    assert_eq!(int_val.value_type(), ValueType::Int);
-    assert_eq!(int_val.as_int().expect("Failed to get int"), 42);
+    assert!(matches!(int_val, Value::Int(_)));
+    if let Value::Int(value) = int_val {
+        assert_eq!(value.as_int(), 42);
+    } else {
+        unreachable!();
+    }
 
     // Test boolean
     let bool_val = state
         .eval_from_string("true", "<eval>")
         .expect("Failed to evaluate bool");
-    assert_eq!(bool_val.value_type(), ValueType::Bool);
-    assert!(bool_val.as_bool().expect("Failed to get bool"));
+    assert!(matches!(bool_val, Value::Bool(_)));
+    if let Value::Bool(value) = bool_val {
+        assert_eq!(value.as_bool(), true);
+    } else {
+        unreachable!();
+    }
 
     // Test string
-    let str_val = state
+    let string_val = state
         .eval_from_string("\"hello\"", "<eval>")
         .expect("Failed to evaluate string");
-    assert_eq!(str_val.value_type(), ValueType::String);
-    assert_eq!(str_val.as_string().expect("Failed to get string"), "hello");
+    assert!(matches!(string_val, Value::String(_)));
+    if let Value::String(value) = string_val {
+        assert_eq!(value.as_string(), "hello");
+    } else {
+        unreachable!();
+    }
 }
 
 #[test]
@@ -78,35 +94,29 @@ fn test_value_formatting() {
         .eval_from_string("42", "<eval>")
         .expect("Failed to evaluate int");
     assert_eq!(format!("{int_val}"), "42");
-    assert_eq!(format!("{int_val:?}"), "Value::Int(42)");
-    assert_eq!(int_val.to_nix_string().expect("Failed to format"), "42");
+    assert_eq!(format!("{int_val:?}"), "Value::Int(NixInt(42))");
 
     // Test boolean formatting
-    let bool_val = state
+    let true_val = state
         .eval_from_string("true", "<eval>")
         .expect("Failed to evaluate bool");
-    assert_eq!(format!("{bool_val}"), "true");
-    assert_eq!(format!("{bool_val:?}"), "Value::Bool(true)");
-    assert_eq!(bool_val.to_nix_string().expect("Failed to format"), "true");
+    assert_eq!(format!("{true_val}"), "true");
+    assert_eq!(format!("{true_val:?}"), "Value::Bool(NixBool(true))");
 
     let false_val = state
         .eval_from_string("false", "<eval>")
         .expect("Failed to evaluate bool");
     assert_eq!(format!("{false_val}"), "false");
-    assert_eq!(
-        false_val.to_nix_string().expect("Failed to format"),
-        "false"
-    );
+    assert_eq!(format!("{false_val:?}"), "Value::Bool(NixBool(false))");
 
     // Test string formatting
     let str_val = state
         .eval_from_string("\"hello world\"", "<eval>")
         .expect("Failed to evaluate string");
     assert_eq!(format!("{str_val}"), "hello world");
-    assert_eq!(format!("{str_val:?}"), "Value::String(\"hello world\")");
     assert_eq!(
-        str_val.to_nix_string().expect("Failed to format"),
-        "\"hello world\""
+        format!("{str_val:?}"),
+        "Value::String(NixString(\"hello world\"))"
     );
 
     // Test string with quotes
@@ -115,8 +125,8 @@ fn test_value_formatting() {
         .expect("Failed to evaluate quoted string");
     assert_eq!(format!("{quoted_str}"), "say \"hello\"");
     assert_eq!(
-        quoted_str.to_nix_string().expect("Failed to format"),
-        "\"say \\\"hello\\\"\""
+        format!("{quoted_str:?}"),
+        "Value::String(NixString(say \"hello\"))"
     );
 
     // Test null formatting
@@ -124,8 +134,7 @@ fn test_value_formatting() {
         .eval_from_string("null", "<eval>")
         .expect("Failed to evaluate null");
     assert_eq!(format!("{null_val}"), "null");
-    assert_eq!(format!("{null_val:?}"), "Value::Null");
-    assert_eq!(null_val.to_nix_string().expect("Failed to format"), "null");
+    assert_eq!(format!("{null_val:?}"), "Value::Null(NixNull)");
 
     // Test collection formatting
     let attrs_val = state
diff --git a/nixide/src/expr/values/attrs.rs b/nixide/src/expr/values/attrs.rs
index 43d8884..8008bf7 100644
--- a/nixide/src/expr/values/attrs.rs
+++ b/nixide/src/expr/values/attrs.rs
@@ -28,13 +28,13 @@ impl Drop for NixAttrs {
 
 impl Display for NixAttrs {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<attrs>")
+        write!(f, "{{ <attrs> }}")
     }
 }
 
 impl Debug for NixAttrs {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixAttrs")
+        write!(f, "NixAttrs({{ <attrs> }})") // XXX: TODO: format attrNames into here
     }
 }
 
diff --git a/nixide/src/expr/values/bool.rs b/nixide/src/expr/values/bool.rs
index 9aa17e5..d604c94 100644
--- a/nixide/src/expr/values/bool.rs
+++ b/nixide/src/expr/values/bool.rs
@@ -27,13 +27,13 @@ impl Drop for NixBool {
 
 impl Display for NixBool {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<bool>")
+        write!(f, "{}", self.value())
     }
 }
 
 impl Debug for NixBool {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixBool(${})", self.value)
+        write!(f, "NixBool({})", self.value)
     }
 }
 
@@ -80,7 +80,12 @@ impl NixBool {
     /// Returns a shared reference to the underlying value.
     ///
     #[inline]
-    fn value(&self) -> &bool {
+    pub fn value(&self) -> &bool {
         &self.value
     }
+
+    #[inline]
+    pub fn as_bool(&self) -> bool {
+        self.value
+    }
 }
diff --git a/nixide/src/expr/values/float.rs b/nixide/src/expr/values/float.rs
index 82b635a..1187821 100644
--- a/nixide/src/expr/values/float.rs
+++ b/nixide/src/expr/values/float.rs
@@ -26,13 +26,13 @@ impl Drop for NixFloat {
 
 impl Display for NixFloat {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<float>")
+        write!(f, "{}", self.value())
     }
 }
 
 impl Debug for NixFloat {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixFloat(${})", self.value())
+        write!(f, "NixFloat({})", self.value())
     }
 }
 
@@ -79,7 +79,12 @@ impl NixFloat {
     /// Returns a shared reference to the underlying value.
     ///
     #[inline]
-    fn value(&self) -> &f64 {
+    pub fn value(&self) -> &f64 {
         &self.value
     }
+
+    #[inline]
+    pub fn as_float(&self) -> f64 {
+        self.value
+    }
 }
diff --git a/nixide/src/expr/values/function.rs b/nixide/src/expr/values/function.rs
index 895128f..5cf15a2 100644
--- a/nixide/src/expr/values/function.rs
+++ b/nixide/src/expr/values/function.rs
@@ -74,14 +74,8 @@ impl NixValue for NixFunction {
     }
 }
 
-// impl Fn<(Value,)> for NixFunction {
-//     extern "rust-call" fn call(&self, args: (Value,)) -> Value {
-//         args.0
-//     }
-// }
-
 impl NixFunction {
-    fn call<T>(&self, arg: &T) -> Value
+    pub fn call<T>(&self, arg: &T) -> Value
     where
         T: NixValue,
     {
@@ -104,7 +98,7 @@ impl NixFunction {
         Value::from((inner, self.state.clone()))
     }
 
-    fn call_many<T>(&self, args: &[&T]) -> Value
+    pub fn call_many<T>(&self, args: &[&T]) -> Value
     where
         T: NixValue,
     {
@@ -128,3 +122,13 @@ impl NixFunction {
         Value::from((inner, self.state.clone()))
     }
 }
+
+// #[cfg(nightly)]
+// impl<T> Fn<(&T,)> for NixFunction
+// where
+//     T: NixValue,
+// {
+//     extern "rust-call" fn call(&self, args: (&T,)) -> Value {
+//         self.call(args.0)
+//     }
+// }
diff --git a/nixide/src/expr/values/int.rs b/nixide/src/expr/values/int.rs
index 3b381da..eccd7ef 100644
--- a/nixide/src/expr/values/int.rs
+++ b/nixide/src/expr/values/int.rs
@@ -26,13 +26,13 @@ impl Drop for NixInt {
 
 impl Display for NixInt {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<int>")
+        write!(f, "{}", self.value())
     }
 }
 
 impl Debug for NixInt {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixInt(${})", self.value())
+        write!(f, "NixInt({})", self.value())
     }
 }
 
@@ -77,7 +77,12 @@ impl NixInt {
     /// Returns a shared reference to the underlying value.
     ///
     #[inline]
-    fn value(&self) -> &i64 {
+    pub fn value(&self) -> &i64 {
         &self.value
     }
+
+    #[inline]
+    pub fn as_int(&self) -> i64 {
+        self.value
+    }
 }
diff --git a/nixide/src/expr/values/list.rs b/nixide/src/expr/values/list.rs
index 96dd9f5..c062a87 100644
--- a/nixide/src/expr/values/list.rs
+++ b/nixide/src/expr/values/list.rs
@@ -26,13 +26,13 @@ impl Drop for NixList {
 
 impl Display for NixList {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<list>")
+        write!(f, "[ <list> ]")
     }
 }
 
 impl Debug for NixList {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixList")
+        write!(f, "NixList([ <list> ])")
     }
 }
 
@@ -76,7 +76,7 @@ impl NixValue for NixList {
 impl NixList {
     /// Forces the evaluation on all elements of the list.
     ///
-    fn as_vec(&self) -> Vec<Value> {
+    pub fn as_vec(&self) -> Vec<Value> {
         // XXX: TODO: should I just return a LazyArray instead?
         let mut value = Vec::new();
         for i in 0..self.len() {
@@ -86,7 +86,7 @@ impl NixList {
         value
     }
 
-    fn as_vec_lazy(&self) -> Vec<NixThunk> {
+    pub fn as_vec_lazy(&self) -> Vec<NixThunk> {
         // XXX: TODO: should I just return a LazyArray instead?
         let mut value = Vec::new();
         for i in 0..self.len() {
@@ -99,14 +99,14 @@ impl NixList {
     /// Get the length of a list. This function preserves
     /// laziness and does not evaluate the internal fields.
     ///
-    fn len(&self) -> u32 {
+    pub fn len(&self) -> u32 {
         wrap::nix_fn!(|ctx: &ErrorContext| unsafe {
             sys::nix_get_list_size(ctx.as_ptr(), self.as_ptr())
         })
         .unwrap_or_else(|err| panic_issue_call_failed!("{}", err))
     }
 
-    fn get(&self, index: u32) -> Value {
+    pub fn get(&self, index: u32) -> Value {
         let inner = wrap::nix_ptr_fn!(|ctx: &ErrorContext| unsafe {
             sys::nix_get_list_byidx(
                 ctx.as_ptr(),
@@ -120,7 +120,7 @@ impl NixList {
         Value::from((inner, self.state.clone()))
     }
 
-    fn get_lazy(&self, index: u32) -> NixThunk {
+    pub fn get_lazy(&self, index: u32) -> NixThunk {
         let inner = wrap::nix_ptr_fn!(|ctx: &ErrorContext| unsafe {
             sys::nix_get_list_byidx_lazy(
                 ctx.as_ptr(),
diff --git a/nixide/src/expr/values/mod.rs b/nixide/src/expr/values/mod.rs
index 7d2ff7d..27fd5f6 100644
--- a/nixide/src/expr/values/mod.rs
+++ b/nixide/src/expr/values/mod.rs
@@ -12,7 +12,7 @@ mod thunk;
 
 pub use attrs::NixAttrs;
 pub use bool::NixBool;
-pub use external::NixExternal;
+// pub use external::NixExternal;
 // pub use failed::NixFailed; // only in latest nix version
 pub use float::NixFloat;
 pub use function::NixFunction;
@@ -24,7 +24,7 @@ pub use string::NixString;
 pub use thunk::NixThunk;
 
 use std::cell::RefCell;
-use std::fmt::{Debug, Display};
+use std::fmt::{Debug, Display, Formatter, Result as FmtResult};
 use std::ptr::NonNull;
 use std::rc::Rc;
 
@@ -107,12 +107,8 @@ pub enum Value {
 
     /// TODO
     Function(NixFunction),
-
-    /// TODO
-    External(NixExternal),
-
-    /// TODO
-    Failed(NixFailed),
+    // External(NixExternal),
+    // Failed(NixFailed),
 }
 
 impl From<(NonNull<sys::nix_value>, Rc<RefCell<EvalState>>)> for Value {
@@ -142,13 +138,61 @@ impl From<(NonNull<sys::nix_value>, Rc<RefCell<EvalState>>)> for Value {
             ValueType_NIX_TYPE_FUNCTION => {
                 Value::Function(<NixFunction as NixValue>::from(inner, state))
             },
-            ValueType_NIX_TYPE_EXTERNAL => {
-                Value::External(<NixExternal as NixValue>::from(inner, state))
-            },
-            // | sys::ValueType_NIX_TYPE_FAILED => {
+            // ValueType_NIX_TYPE_EXTERNAL => {
+            //     Value::External(<NixExternal as NixValue>::from(inner, state))
+            // },
+            // ValueType_NIX_TYPE_FAILED => {
             //     Value::Failed(<NixFailed as NixValue>::from(inner, state))
             // },
             _ => unreachable!(),
         }
     }
 }
+
+impl Display for Value {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        match self {
+            Value::Thunk(value) => write!(f, "{value}"),
+            Value::Int(value) => write!(f, "{value}"),
+            Value::Float(value) => write!(f, "{value}"),
+            Value::Bool(value) => write!(f, "{value}"),
+            Value::String(value) => write!(f, "{value}"),
+            Value::Path(value) => write!(f, "{value}"),
+            Value::Null(value) => write!(f, "{value}"),
+            Value::Attrs(value) => write!(f, "{value}"),
+            Value::List(value) => write!(f, "{value}"),
+            Value::Function(value) => write!(f, "{value}"),
+            // Value::External(value) => write!(f, "{value}"),
+            // Value::Failed(value) => write!(f, "{value}"),
+        }
+    }
+}
+
+impl Debug for Value {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        match self {
+            Value::Thunk(value) => write!(f, "Value::Thunk({value:?})"),
+            Value::Int(value) => write!(f, "Value::Int({value:?})"),
+            Value::Float(value) => write!(f, "Value::Float({value:?})"),
+            Value::Bool(value) => write!(f, "Value::Bool({value:?})"),
+            Value::String(value) => write!(f, "Value::String({value:?})"),
+            Value::Path(value) => write!(f, "Value::Path({value:?})"),
+            Value::Null(value) => write!(f, "Value::Null({value:?})"),
+            Value::Attrs(value) => write!(f, "Value::Attrs({value:?})"),
+            Value::List(value) => write!(f, "Value::List({value:?})"),
+            Value::Function(value) => write!(f, "Value::Function({value:?})"),
+            // Value::External(value) => write!(f, "Value::External({value:?})"),
+            // Value::Failed(value) => write!(f, "Value::Failed({value:?})"),
+        }
+    }
+}
+
+// macro_rules! is_type {
+//     ($expr:expr, $tt:tt) => {{
+//         match $expr {
+//             $tt => true,
+//             _ => false,
+//         }
+//     }};
+// }
+// pub(self) use is_type;
diff --git a/nixide/src/expr/values/path.rs b/nixide/src/expr/values/path.rs
index 145b2d2..9a7fdb2 100644
--- a/nixide/src/expr/values/path.rs
+++ b/nixide/src/expr/values/path.rs
@@ -29,13 +29,13 @@ impl Drop for NixPath {
 
 impl Display for NixPath {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<path>")
+        write!(f, "{}", self.value.display())
     }
 }
 
 impl Debug for NixPath {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixPath(\"${}\")", self.value().display())
+        write!(f, "NixPath(\"{}\")", self.value().display())
     }
 }
 
@@ -82,7 +82,12 @@ impl NixPath {
     /// Returns a shared reference to the underlying value.
     ///
     #[inline]
-    fn value(&self) -> &PathBuf {
+    pub fn value(&self) -> &PathBuf {
         &self.value
     }
+
+    #[inline]
+    pub fn as_path(&self) -> PathBuf {
+        self.value.clone()
+    }
 }
diff --git a/nixide/src/expr/values/string.rs b/nixide/src/expr/values/string.rs
index 2ceeb41..9ee305a 100644
--- a/nixide/src/expr/values/string.rs
+++ b/nixide/src/expr/values/string.rs
@@ -28,13 +28,13 @@ impl Drop for NixString {
 
 impl Display for NixString {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "<string>")
+        write!(f, "{}", self.value())
     }
 }
 
 impl Debug for NixString {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        write!(f, "NixString(\"${}\")", self.value())
+        write!(f, "NixString(\"{}\")", self.value())
     }
 }
 
@@ -86,7 +86,12 @@ impl NixString {
     /// Returns a shared reference to the underlying value.
     ///
     #[inline]
-    fn value(&self) -> &String {
+    pub fn value(&self) -> &String {
         &self.value
     }
+
+    #[inline]
+    pub fn as_string(&self) -> String {
+        self.value.clone()
+    }
 }
diff --git a/nixide/src/expr/values/thunk.rs b/nixide/src/expr/values/thunk.rs
index 19a5470..5fbe0f7 100644
--- a/nixide/src/expr/values/thunk.rs
+++ b/nixide/src/expr/values/thunk.rs
@@ -65,11 +65,11 @@ impl NixValue for NixThunk {
 }
 
 impl NixThunk {
-    fn to_inner(self) -> NonNull<sys::nix_value> {
-        self.inner
-    }
+    // fn to_inner(self) -> NonNull<sys::nix_value> {
+    //     self.inner
+    // }
 
-    fn eval(self) -> Value {
+    pub fn eval(self) -> Value {
         wrap::nix_fn!(|ctx: &ErrorContext| unsafe {
             sys::nix_value_force(
                 ctx.as_ptr(),
diff --git a/nixide/src/lib.rs b/nixide/src/lib.rs
index 4601253..ccbccf1 100644
--- a/nixide/src/lib.rs
+++ b/nixide/src/lib.rs
@@ -1,6 +1,7 @@
 // #![warn(missing_docs)]
 
 #![cfg_attr(nightly, feature(fn_traits))]
+#![cfg_attr(nightly, feature(unboxed_closures))]
 
 pub extern crate libc;
 pub extern crate nixide_sys as sys;