diff --git a/nix-js/runtime-ts/src/builtins/io.ts b/nix-js/runtime-ts/src/builtins/io.ts
index 764a39a..fc534b7 100644
--- a/nix-js/runtime-ts/src/builtins/io.ts
+++ b/nix-js/runtime-ts/src/builtins/io.ts
@@ -3,7 +3,7 @@
  * Implemented via Rust ops exposed through deno_core
  */
 
-import { forceAttrs, forceBool, forceList, forceStringNoCtx, forceStringValue } from "../type-assert";
+import { forceAttrs, forceBool, forceFunction, forceList, forceStringNoCtx, forceStringValue } from "../type-assert";
 import type { NixValue, NixAttrs, NixPath } from "../types";
 import { isNixPath, IS_PATH, CatchableError } from "../types";
 import { force } from "../thunk";
@@ -333,7 +333,7 @@ export const pathExists = (path: NixValue): boolean => {
  * Parameters (attribute set):
  * - path (required): Path to add to the store
  * - name (optional): Name to use in store path (defaults to basename)
- * - filter (optional): Function (path, type) -> bool (NOT IMPLEMENTED YET)
+ * - filter (optional): Function (path, type) -> bool
  * - recursive (optional): Boolean, default true (NAR vs flat hashing)
  * - sha256 (optional): Expected SHA-256 hash (hex-encoded)
  *
@@ -366,9 +366,30 @@ export const path = (args: NixValue): string => {
   // Optional: sha256 parameter
   const sha256 = "sha256" in attrs ? forceStringValue(attrs.sha256) : null;
 
-  // TODO: Handle filter parameter
+  // Handle filter parameter
   if ("filter" in attrs) {
-    throw new Error("builtins.path: 'filter' parameter is not yet implemented");
+    const filterFn = forceFunction(attrs.filter);
+
+    const entries: [string, string][] = Deno.core.ops.op_walk_dir(pathStr);
+
+    const includePaths: string[] = [];
+    for (const [relPath, fileType] of entries) {
+      const fullPath = pathStr + "/" + relPath;
+      const innerFn = forceFunction(filterFn(fullPath));
+      const shouldInclude = force(innerFn(fileType));
+      if (shouldInclude === true) {
+        includePaths.push(relPath);
+      }
+    }
+
+    const storePath: string = Deno.core.ops.op_add_filtered_path(
+      pathStr,
+      name,
+      recursive,
+      sha256,
+      includePaths,
+    );
+    return storePath;
   }
 
   // Call Rust op to add path to store
diff --git a/nix-js/runtime-ts/src/types/global.d.ts b/nix-js/runtime-ts/src/types/global.d.ts
index 9d887bc..0eafc57 100644
--- a/nix-js/runtime-ts/src/types/global.d.ts
+++ b/nix-js/runtime-ts/src/types/global.d.ts
@@ -83,6 +83,14 @@ declare global {
         function op_to_file(name: string, contents: string, references: string[]): string;
         function op_copy_path_to_store(path: string): string;
         function op_get_env(key: string): string;
+        function op_walk_dir(path: string): [string, string][];
+        function op_add_filtered_path(
+          path: string,
+          name: string | null,
+          recursive: boolean,
+          sha256: string | null,
+          include_paths: string[],
+        ): string;
       }
     }
   }
diff --git a/nix-js/src/error.rs b/nix-js/src/error.rs
index 1f8ead5..06a58a6 100644
--- a/nix-js/src/error.rs
+++ b/nix-js/src/error.rs
@@ -44,6 +44,13 @@ impl From<Source> for NamedSource<Arc<str>> {
 }
 
 impl Source {
+    pub fn new_file(path: PathBuf) -> std::io::Result<Self> {
+        Ok(Source {
+            src: std::fs::read_to_string(&path)?.into(),
+            ty: crate::error::SourceType::File(Arc::new(path)),
+        })
+    }
+
     pub fn new_eval(src: String) -> Result<Self> {
         Ok(Self {
             ty: std::env::current_dir()
diff --git a/nix-js/src/nix_hash.rs b/nix-js/src/nix_hash.rs
index 5ffdd8c..908da25 100644
--- a/nix-js/src/nix_hash.rs
+++ b/nix-js/src/nix_hash.rs
@@ -41,6 +41,47 @@ pub fn nix_base32_encode(bytes: &[u8]) -> String {
     result
 }
 
+pub fn nix_base32_decode(input: &str) -> Option<Vec<u8>> {
+    let len = input.len() * 5 / 8;
+    let mut bytes = vec![0u8; len];
+
+    for (n, ch) in input.chars().rev().enumerate() {
+        let digit = NIX_BASE32_CHARS.iter().position(|&c| c == ch as u8)? as u16;
+        let b = n * 5;
+        let i = b / 8;
+        let j = b % 8;
+        if i < len {
+            bytes[i] |= (digit << j) as u8;
+        }
+        if j > 3 && i + 1 < len {
+            bytes[i + 1] |= (digit >> (8 - j)) as u8;
+        }
+    }
+
+    Some(bytes)
+}
+
+pub fn decode_hash_to_hex(hash_str: &str) -> Option<String> {
+    if hash_str.starts_with("sha256:") {
+        let rest = &hash_str[7..];
+        return decode_hash_to_hex(rest);
+    }
+    if hash_str.starts_with("sha256-") {
+        let base64_str = &hash_str[7..];
+        use base64::{Engine, engine::general_purpose::STANDARD};
+        let bytes = STANDARD.decode(base64_str).ok()?;
+        return Some(hex::encode(bytes));
+    }
+    if hash_str.len() == 64 && hash_str.chars().all(|c| c.is_ascii_hexdigit()) {
+        return Some(hash_str.to_string());
+    }
+    if hash_str.len() == 52 {
+        let bytes = nix_base32_decode(hash_str)?;
+        return Some(hex::encode(bytes));
+    }
+    None
+}
+
 pub fn make_store_path(store_dir: &str, ty: &str, hash_hex: &str, name: &str) -> String {
     let s = format!("{}:sha256:{}:{}:{}", ty, hash_hex, store_dir, name);
 
diff --git a/nix-js/src/runtime.rs b/nix-js/src/runtime.rs
index 385a37b..4361c55 100644
--- a/nix-js/src/runtime.rs
+++ b/nix-js/src/runtime.rs
@@ -58,6 +58,8 @@ fn runtime_extension<Ctx: RuntimeContext>() -> Extension {
         op_to_file::<Ctx>(),
         op_copy_path_to_store::<Ctx>(),
         op_get_env(),
+        op_walk_dir(),
+        op_add_filtered_path::<Ctx>(),
     ];
     ops.extend(crate::fetcher::register_ops::<Ctx>());
 
@@ -140,12 +142,8 @@ fn op_import<Ctx: RuntimeContext>(
 
     tracing::info!("Importing file: {}", absolute_path.display());
 
-    let content = std::fs::read_to_string(absolute_path.as_path())
+    let source = Source::new_file(absolute_path.clone())
         .map_err(|e| format!("Failed to read {}: {}", absolute_path.display(), e))?;
-    let source = Source {
-        ty: crate::error::SourceType::File(absolute_path.into()),
-        src: content.into(),
-    };
 
     tracing::debug!("Compiling file");
     ctx.add_source(source.clone());
@@ -161,7 +159,17 @@ fn op_read_file(#[string] path: String) -> std::result::Result<String, NixError>
 
 #[deno_core::op2(fast)]
 fn op_path_exists(#[string] path: String) -> bool {
-    std::path::Path::new(&path).exists()
+    let must_be_dir = path.ends_with('/') || path.ends_with("/.");
+    let p = Path::new(&path);
+
+    if must_be_dir {
+        match std::fs::metadata(p) {
+            Ok(m) => m.is_dir(),
+            Err(_) => false,
+        }
+    } else {
+        std::fs::symlink_metadata(p).is_ok()
+    }
 }
 
 #[deno_core::op2]
@@ -400,7 +408,8 @@ fn op_add_path<Ctx: RuntimeContext>(
     });
 
     let computed_hash = if recursive {
-        compute_nar_hash(path_obj)?
+        crate::nar::compute_nar_hash(path_obj)
+            .map_err(|e| NixError::from(format!("failed to compute NAR hash: {}", e)))?
     } else {
         if !path_obj.is_file() {
             return Err(NixError::from(
@@ -415,60 +424,35 @@ fn op_add_path<Ctx: RuntimeContext>(
         hex::encode(hasher.finalize())
     };
 
-    if let Some(expected_hash) = sha256
-        && computed_hash != expected_hash
-    {
-        return Err(NixError::from(format!(
-            "hash mismatch for path '{}': expected {}, got {}",
-            path, expected_hash, computed_hash
-        )));
+    if let Some(expected_hash) = sha256 {
+        let expected_hex = crate::nix_hash::decode_hash_to_hex(&expected_hash)
+            .ok_or_else(|| NixError::from(format!("invalid hash format: {}", expected_hash)))?;
+        if computed_hash != expected_hex {
+            return Err(NixError::from(format!(
+                "hash mismatch for path '{}': expected {}, got {}",
+                path, expected_hex, computed_hash
+            )));
+        }
     }
 
     let ctx: &Ctx = state.get_ctx();
     let store = ctx.get_store();
 
-    let store_path = store
-        .add_to_store_from_path(&computed_name, path_obj, vec![])
-        .map_err(|e| NixError::from(format!("failed to add path to store: {}", e)))?;
+    let store_path = if recursive {
+        store
+            .add_to_store_from_path(&computed_name, path_obj, vec![])
+            .map_err(|e| NixError::from(format!("failed to add path to store: {}", e)))?
+    } else {
+        let contents = fs::read(path_obj)
+            .map_err(|e| NixError::from(format!("failed to read '{}': {}", path, e)))?;
+        store
+            .add_to_store(&computed_name, &contents, false, vec![])
+            .map_err(|e| NixError::from(format!("failed to add to store: {}", e)))?
+    };
 
     Ok(store_path)
 }
 
-fn compute_nar_hash(path: &std::path::Path) -> std::result::Result<String, NixError> {
-    use sha2::{Digest, Sha256};
-    use std::fs;
-
-    if path.is_file() {
-        let contents =
-            fs::read(path).map_err(|e| NixError::from(format!("failed to read file: {}", e)))?;
-        let mut hasher = Sha256::new();
-        hasher.update(&contents);
-        Ok(hex::encode(hasher.finalize()))
-    } else if path.is_dir() {
-        let mut entries: Vec<_> = fs::read_dir(path)
-            .map_err(|e| NixError::from(format!("failed to read directory: {}", e)))?
-            .filter_map(std::result::Result::ok)
-            .collect();
-
-        entries.sort_by_key(|e| e.file_name());
-
-        let mut hasher = Sha256::new();
-        for entry in entries {
-            let entry_path = entry.path();
-            let entry_name = entry.file_name();
-
-            hasher.update(entry_name.to_string_lossy().as_bytes());
-
-            let entry_hash = compute_nar_hash(&entry_path)?;
-            hasher.update(entry_hash.as_bytes());
-        }
-
-        Ok(hex::encode(hasher.finalize()))
-    } else {
-        Ok(String::new())
-    }
-}
-
 #[deno_core::op2]
 #[string]
 fn op_store_path<Ctx: RuntimeContext>(
@@ -546,6 +530,161 @@ fn op_get_env(#[string] key: String) -> std::result::Result<String, NixError> {
     }
 }
 
+#[deno_core::op2]
+#[serde]
+fn op_walk_dir(
+    #[string] path: String,
+) -> std::result::Result<Vec<(String, String)>, NixError> {
+    fn walk_recursive(
+        base: &Path,
+        current: &Path,
+        results: &mut Vec<(String, String)>,
+    ) -> std::result::Result<(), NixError> {
+        let entries = std::fs::read_dir(current)
+            .map_err(|e| NixError::from(format!("failed to read directory: {}", e)))?;
+
+        for entry in entries {
+            let entry =
+                entry.map_err(|e| NixError::from(format!("failed to read entry: {}", e)))?;
+            let path = entry.path();
+            let rel_path = path
+                .strip_prefix(base)
+                .map_err(|e| NixError::from(format!("failed to get relative path: {}", e)))?
+                .to_string_lossy()
+                .to_string();
+
+            let file_type = entry
+                .file_type()
+                .map_err(|e| NixError::from(format!("failed to get file type: {}", e)))?;
+
+            let type_str = if file_type.is_dir() {
+                "directory"
+            } else if file_type.is_symlink() {
+                "symlink"
+            } else {
+                "regular"
+            };
+
+            results.push((rel_path.clone(), type_str.to_string()));
+
+            if file_type.is_dir() {
+                walk_recursive(base, &path, results)?;
+            }
+        }
+        Ok(())
+    }
+
+    let path = Path::new(&path);
+    if !path.is_dir() {
+        return Err(NixError::from(format!(
+            "{} is not a directory",
+            path.display()
+        )));
+    }
+
+    let mut results = Vec::new();
+    walk_recursive(path, path, &mut results)?;
+    Ok(results)
+}
+
+#[deno_core::op2]
+#[string]
+fn op_add_filtered_path<Ctx: RuntimeContext>(
+    state: &mut OpState,
+    #[string] src_path: String,
+    #[string] name: Option<String>,
+    recursive: bool,
+    #[string] sha256: Option<String>,
+    #[serde] include_paths: Vec<String>,
+) -> std::result::Result<String, NixError> {
+    use sha2::{Digest, Sha256};
+    use std::fs;
+
+    let src = Path::new(&src_path);
+    if !src.exists() {
+        return Err(NixError::from(format!("path '{}' does not exist", src_path)));
+    }
+
+    let computed_name = name.unwrap_or_else(|| {
+        src.file_name()
+            .and_then(|n| n.to_str())
+            .unwrap_or("source")
+            .to_string()
+    });
+
+    let temp_dir = tempfile::tempdir()
+        .map_err(|e| NixError::from(format!("failed to create temp dir: {}", e)))?;
+    let dest = temp_dir.path().join(&computed_name);
+
+    fs::create_dir_all(&dest)
+        .map_err(|e| NixError::from(format!("failed to create dest dir: {}", e)))?;
+
+    for rel_path in &include_paths {
+        let src_file = src.join(rel_path);
+        let dest_file = dest.join(rel_path);
+
+        if let Some(parent) = dest_file.parent() {
+            fs::create_dir_all(parent)
+                .map_err(|e| NixError::from(format!("failed to create dir: {}", e)))?;
+        }
+
+        let metadata = fs::symlink_metadata(&src_file)
+            .map_err(|e| NixError::from(format!("failed to read metadata: {}", e)))?;
+
+        if metadata.is_symlink() {
+            let target = fs::read_link(&src_file)
+                .map_err(|e| NixError::from(format!("failed to read symlink: {}", e)))?;
+            #[cfg(unix)]
+            std::os::unix::fs::symlink(&target, &dest_file)
+                .map_err(|e| NixError::from(format!("failed to create symlink: {}", e)))?;
+            #[cfg(not(unix))]
+            return Err(NixError::from("symlinks not supported on this platform"));
+        } else if metadata.is_dir() {
+            fs::create_dir_all(&dest_file)
+                .map_err(|e| NixError::from(format!("failed to create dir: {}", e)))?;
+        } else {
+            fs::copy(&src_file, &dest_file)
+                .map_err(|e| NixError::from(format!("failed to copy file: {}", e)))?;
+        }
+    }
+
+    let computed_hash = if recursive {
+        crate::nar::compute_nar_hash(&dest)
+            .map_err(|e| NixError::from(format!("failed to compute NAR hash: {}", e)))?
+    } else {
+        if !dest.is_file() {
+            return Err(NixError::from(
+                "when 'recursive' is false, path must be a regular file",
+            ));
+        }
+        let contents = fs::read(&dest)
+            .map_err(|e| NixError::from(format!("failed to read file: {}", e)))?;
+        let mut hasher = Sha256::new();
+        hasher.update(&contents);
+        hex::encode(hasher.finalize())
+    };
+
+    if let Some(expected_hash) = sha256 {
+        let expected_hex = crate::nix_hash::decode_hash_to_hex(&expected_hash)
+            .ok_or_else(|| NixError::from(format!("invalid hash format: {}", expected_hash)))?;
+        if computed_hash != expected_hex {
+            return Err(NixError::from(format!(
+                "hash mismatch for path '{}': expected {}, got {}",
+                src_path, expected_hex, computed_hash
+            )));
+        }
+    }
+
+    let ctx: &Ctx = state.get_ctx();
+    let store = ctx.get_store();
+
+    let store_path = store
+        .add_to_store_from_path(&computed_name, &dest, vec![])
+        .map_err(|e| NixError::from(format!("failed to add path to store: {}", e)))?;
+
+    Ok(store_path)
+}
+
 pub(crate) struct Runtime<Ctx: RuntimeContext> {
     js_runtime: JsRuntime,
     is_thunk_symbol: v8::Global<v8::Symbol>,
diff --git a/nix-js/tests/lang.rs b/nix-js/tests/lang.rs
index 7cf2c2a..8653661 100644
--- a/nix-js/tests/lang.rs
+++ b/nix-js/tests/lang.rs
@@ -12,15 +12,20 @@ fn get_lang_dir() -> PathBuf {
     PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("tests/lang")
 }
 
-fn eval_file(name: &str) -> Result<Value, String> {
+fn eval_file(name: &str) -> Result<(Value, Source), String> {
     let lang_dir = get_lang_dir();
     let nix_path = lang_dir.join(format!("{name}.nix"));
 
     let expr = format!(r#"import "{}""#, nix_path.display());
 
     let mut ctx = Context::new().map_err(|e| e.to_string())?;
-    let source = Source::new_eval(expr).map_err(|e| e.to_string())?;
-    ctx.eval_code(source).map_err(|e| e.to_string())
+    let source = Source {
+        ty: nix_js::error::SourceType::File(nix_path.into()),
+        src: expr.into(),
+    };
+    ctx.eval_code(source.clone())
+        .map(|val| (val, source))
+        .map_err(|e| e.to_string())
 }
 
 fn read_expected(name: &str) -> String {
@@ -47,8 +52,17 @@ macro_rules! eval_okay_test {
                 .replace("r#", "");
             let result = eval_file(&test_name);
             match result {
-                Ok(value) => {
+                Ok((value, source)) => {
                     let actual = format_value(&value);
+                    let actual = actual.replace(
+                        source
+                            .get_dir()
+                            .parent()
+                            .unwrap()
+                            .to_string_lossy()
+                            .as_ref(),
+                        "/pwd",
+                    );
                     let expected = read_expected(&test_name);
                     assert_eq!(actual, expected, "Output mismatch for {}", test_name);
                 }
@@ -86,8 +100,14 @@ eval_okay_test!(attrs2);
 eval_okay_test!(attrs3);
 eval_okay_test!(attrs4);
 eval_okay_test!(attrs5);
-eval_okay_test!(#[ignore = "__overrides is not supported"] attrs6);
-eval_okay_test!(#[ignore = "requires --arg/--argstr CLI flags"] autoargs);
+eval_okay_test!(
+    #[ignore = "__overrides is not supported"]
+    attrs6
+);
+eval_okay_test!(
+    #[ignore = "requires --arg/--argstr CLI flags"]
+    autoargs
+);
 eval_okay_test!(backslash_newline_1);
 eval_okay_test!(backslash_newline_2);
 eval_okay_test!(baseNameOf);
@@ -102,7 +122,10 @@ eval_okay_test!(concatmap);
 eval_okay_test!(concatstringssep);
 eval_okay_test!(context);
 eval_okay_test!(context_introspection);
-eval_okay_test!(#[ignore = "not implemented: convertHash"] convertHash);
+eval_okay_test!(
+    #[ignore = "not implemented: convertHash"]
+    convertHash
+);
 eval_okay_test!(curpos);
 eval_okay_test!(deepseq);
 eval_okay_test!(delayed_with);
@@ -117,7 +140,10 @@ eval_okay_test!(empty_args);
 eval_okay_test!(eq);
 eval_okay_test!(eq_derivations);
 eval_okay_test!(filter);
-eval_okay_test!(#[ignore = "not implemented: flakeRefToString"] flake_ref_to_string);
+eval_okay_test!(
+    #[ignore = "not implemented: flakeRefToString"]
+    flake_ref_to_string
+);
 eval_okay_test!(flatten);
 eval_okay_test!(float);
 eval_okay_test!(floor_ceil);
@@ -126,23 +152,39 @@ eval_okay_test!(foldlStrict_lazy_elements);
 eval_okay_test!(foldlStrict_lazy_initial_accumulator);
 eval_okay_test!(fromjson);
 eval_okay_test!(fromjson_escapes);
-eval_okay_test!(#[ignore = "not implemented: fromTOML"] fromTOML);
-eval_okay_test!(#[ignore = "not implemented: fromTOML"] fromTOML_timestamps);
+eval_okay_test!(
+    #[ignore = "not implemented: fromTOML"]
+    fromTOML
+);
+eval_okay_test!(
+    #[ignore = "not implemented: fromTOML"]
+    fromTOML_timestamps
+);
 eval_okay_test!(functionargs);
-eval_okay_test!(#[ignore = "not implemented: hashFile"] hashfile);
-eval_okay_test!(#[ignore = "not implemented: hashString"] hashstring);
+eval_okay_test!(
+    #[ignore = "not implemented: hashFile"]
+    hashfile
+);
+eval_okay_test!(
+    #[ignore = "not implemented: hashString"]
+    hashstring
+);
 eval_okay_test!(getattrpos);
 eval_okay_test!(getattrpos_functionargs);
 eval_okay_test!(getattrpos_undefined);
 eval_okay_test!(getenv, || {
-    unsafe {
-        std::env::set_var("TEST_VAR", "foo")
-    };
+    unsafe { std::env::set_var("TEST_VAR", "foo") };
 });
-eval_okay_test!(#[ignore = "not implemented: hashString"] groupBy);
+eval_okay_test!(
+    #[ignore = "not implemented: hashString"]
+    groupBy
+);
 eval_okay_test!(r#if);
 eval_okay_test!(ind_string);
-eval_okay_test!(#[ignore = "not implemented: scopedImport"] import);
+eval_okay_test!(
+    #[ignore = "not implemented: scopedImport"]
+    import
+);
 eval_okay_test!(inherit_attr_pos);
 eval_okay_test!(inherit_from);
 eval_okay_test!(intersectAttrs);
@@ -156,12 +198,22 @@ eval_okay_test!(merge_dynamic_attrs);
 eval_okay_test!(nested_with);
 eval_okay_test!(new_let);
 eval_okay_test!(null_dynamic_attrs);
-eval_okay_test!(#[ignore = "__overrides is not supported"] overrides);
-eval_okay_test!(#[ignore = "not implemented: parseFlakeRef"] parse_flake_ref);
+eval_okay_test!(
+    #[ignore = "__overrides is not supported"]
+    overrides
+);
+eval_okay_test!(
+    #[ignore = "not implemented: parseFlakeRef"]
+    parse_flake_ref
+);
 eval_okay_test!(partition);
 eval_okay_test!(path);
 eval_okay_test!(pathexists);
-eval_okay_test!(path_string_interpolation);
+eval_okay_test!(path_string_interpolation, || {
+    unsafe {
+        std::env::set_var("HOME", "/fake-home");
+    }
+});
 eval_okay_test!(patterns);
 eval_okay_test!(print);
 eval_okay_test!(readDir);
@@ -177,7 +229,10 @@ eval_okay_test!(remove);
 eval_okay_test!(repeated_empty_attrs);
 eval_okay_test!(repeated_empty_list);
 eval_okay_test!(replacestrings);
-eval_okay_test!(#[ignore = "requires -I CLI flags"] search_path);
+eval_okay_test!(
+    #[ignore = "requires -I CLI flags"]
+    search_path
+);
 eval_okay_test!(scope_1);
 eval_okay_test!(scope_2);
 eval_okay_test!(scope_3);
@@ -194,13 +249,22 @@ eval_okay_test!(substring_context);
 eval_okay_test!(symlink_resolution);
 eval_okay_test!(tail_call_1);
 eval_okay_test!(tojson);
-eval_okay_test!(#[ignore = "not implemented: toXML"] toxml);
-eval_okay_test!(#[ignore = "not implemented: toXML"] toxml2);
+eval_okay_test!(
+    #[ignore = "not implemented: toXML"]
+    toxml
+);
+eval_okay_test!(
+    #[ignore = "not implemented: toXML"]
+    toxml2
+);
 eval_okay_test!(tryeval);
 eval_okay_test!(types);
 eval_okay_test!(versions);
 eval_okay_test!(with);
-eval_okay_test!(#[ignore = "not implemented: hashString"] zipAttrsWith);
+eval_okay_test!(
+    #[ignore = "not implemented: hashString"]
+    zipAttrsWith
+);
 
 eval_fail_test!(fail_abort);
 eval_fail_test!(fail_addDrvOutputDependencies_empty_context);
diff --git a/nix-js/tests/lang/data b/nix-js/tests/lang/data
new file mode 100644
index 0000000..257cc56
--- /dev/null
+++ b/nix-js/tests/lang/data
@@ -0,0 +1 @@
+foo