diff --git a/stdlib/src/sys.rs b/stdlib/src/sys.rs
index 42d264b3..00a45f14 100644
--- a/stdlib/src/sys.rs
+++ b/stdlib/src/sys.rs
@@ -1,14 +1,87 @@
 use crate::{StdFunction, StdlibModule, StdlibRegistry};
-use indexmap::IndexMap;
-use std::cell::RefCell;
 use std::collections::HashMap;
 use std::rc::Rc;
 use techscript_runtime::{
-    context::Capability,
+    context::{Capability, RuntimeContext},
     error::{RuntimeError, RuntimeErrorKind},
     value::RuntimeValue,
 };
 
+fn check_fs_capability(ctx: &RuntimeContext) -> Result<(), RuntimeError> {
+    if !ctx.config.capabilities.contains(&Capability::FileSystem) {
+        return Err(RuntimeError::new(
+            RuntimeErrorKind::InvalidOperation(
+                "Security policy violation: FileSystem capability is denied".to_string(),
+            ),
+            None,
+            None,
+        ));
+    }
+    Ok(())
+}
+
+fn sys_read_file(
+    ctx: &mut RuntimeContext,
+    args: Vec<RuntimeValue>,
+) -> Result<RuntimeValue, RuntimeError> {
+    check_fs_capability(ctx)?;
+    let path = args[0].try_into_string()?;
+    let content = std::fs::read_to_string(path).map_err(|e| {
+        RuntimeError::new(
+            RuntimeErrorKind::InvalidOperation(format!("IO error: {}", e)),
+            None,
+            None,
+        )
+    })?;
+    Ok(RuntimeValue::Str(content))
+}
+
+fn sys_write_file(
+    ctx: &mut RuntimeContext,
+    args: Vec<RuntimeValue>,
+) -> Result<RuntimeValue, RuntimeError> {
+    check_fs_capability(ctx)?;
+    let path = args[0].try_into_string()?;
+    let content = args[1].try_into_string()?;
+    std::fs::write(path, content).map_err(|e| {
+        RuntimeError::new(
+            RuntimeErrorKind::InvalidOperation(format!("IO error: {}", e)),
+            None,
+            None,
+        )
+    })?;
+    Ok(RuntimeValue::Null)
+}
+
+fn sys_exists(
+    ctx: &mut RuntimeContext,
+    args: Vec<RuntimeValue>,
+) -> Result<RuntimeValue, RuntimeError> {
+    check_fs_capability(ctx)?;
+    let path = args[0].try_into_string()?;
+    Ok(RuntimeValue::Bool(std::path::Path::new(&path).exists()))
+}
+
+fn sys_now(
+    _ctx: &mut RuntimeContext,
+    _args: Vec<RuntimeValue>,
+) -> Result<RuntimeValue, RuntimeError> {
+    let start = std::time::SystemTime::now();
+    let since_the_epoch = start
+        .duration_since(std::time::UNIX_EPOCH)
+        .unwrap_or_default();
+    Ok(RuntimeValue::Float(since_the_epoch.as_secs_f64()))
+}
+
+fn sys_sleep(
+    _ctx: &mut RuntimeContext,
+    args: Vec<RuntimeValue>,
+) -> Result<RuntimeValue, RuntimeError> {
+    let ms = args[0].try_into_int()?;
+    std::thread::sleep(std::time::Duration::from_millis(ms as u64));
+    Ok(RuntimeValue::Null)
+}
+
 impl StdlibRegistry {
     pub fn register_sys(&mut self) {
         let mut exports: HashMap<String, Rc<dyn techscript_runtime::function::Callable>> =
@@ -19,27 +92,7 @@ impl StdlibRegistry {
             Rc::new(StdFunction {
                 name: "read_file".to_string(),
                 arity: 1,
-                callback: |ctx, args| {
-                    if !ctx.config.capabilities.contains(&Capability::FileSystem) {
-                        return Err(RuntimeError::new(
-                            RuntimeErrorKind::InvalidOperation(
-                                "Security policy violation: FileSystem capability is denied"
-                                    .to_string(),
-                            ),
-                            None,
-                            None,
-                        ));
-                    }
-                    let path = args[0].try_into_string()?;
-                    let content = std::fs::read_to_string(path).map_err(|e| {
-                        RuntimeError::new(
-                            RuntimeErrorKind::InvalidOperation(format!("IO error: {}", e)),
-                            None,
-                            None,
-                        )
-                    })?;
-                    Ok(RuntimeValue::Str(content))
-                },
+                callback: sys_read_file,
             }),
         );
 
@@ -48,28 +101,7 @@ impl StdlibRegistry {
             Rc::new(StdFunction {
                 name: "write_file".to_string(),
                 arity: 2,
-                callback: |ctx, args| {
-                    if !ctx.config.capabilities.contains(&Capability::FileSystem) {
-                        return Err(RuntimeError::new(
-                            RuntimeErrorKind::InvalidOperation(
-                                "Security policy violation: FileSystem capability is denied"
-                                    .to_string(),
-                            ),
-                            None,
-                            None,
-                        ));
-                    }
-                    let path = args[0].try_into_string()?;
-                    let content = args[1].try_into_string()?;
-                    std::fs::write(path, content).map_err(|e| {
-                        RuntimeError::new(
-                            RuntimeErrorKind::InvalidOperation(format!("IO error: {}", e)),
-                            None,
-                            None,
-                        )
-                    })?;
-                    Ok(RuntimeValue::Null)
-                },
+                callback: sys_write_file,
             }),
         );
 
@@ -78,20 +110,7 @@ impl StdlibRegistry {
             Rc::new(StdFunction {
                 name: "exists".to_string(),
                 arity: 1,
-                callback: |ctx, args| {
-                    if !ctx.config.capabilities.contains(&Capability::FileSystem) {
-                        return Err(RuntimeError::new(
-                            RuntimeErrorKind::InvalidOperation(
-                                "Security policy violation: FileSystem capability is denied"
-                                    .to_string(),
-                            ),
-                            None,
-                            None,
-                        ));
-                    }
-                    let path = args[0].try_into_string()?;
-                    Ok(RuntimeValue::Bool(std::path::Path::new(&path).exists()))
-                },
+                callback: sys_exists,
             }),
         );
 
@@ -112,13 +131,7 @@ impl StdlibRegistry {
             Rc::new(StdFunction {
                 name: "now".to_string(),
                 arity: 0,
-                callback: |_ctx, _args| {
-                    let start = std::time::SystemTime::now();
-                    let since_the_epoch = start
-                        .duration_since(std::time::UNIX_EPOCH)
-                        .unwrap_or_default();
-                    Ok(RuntimeValue::Float(since_the_epoch.as_secs_f64()))
-                },
+                callback: sys_now,
             }),
         );
 
@@ -127,11 +140,7 @@ impl StdlibRegistry {
             Rc::new(StdFunction {
                 name: "sleep".to_string(),
                 arity: 1,
-                callback: |_ctx, args| {
-                    let ms = args[0].try_into_int()?;
-                    std::thread::sleep(std::time::Duration::from_millis(ms as u64));
-                    Ok(RuntimeValue::Null)
-                },
+                callback: sys_sleep,
             }),
         );
 
diff --git a/test_output.log b/test_output.log
new file mode 100644
index 00000000..d8364f42
--- /dev/null
+++ b/test_output.log
@@ -0,0 +1,384 @@
+ Downloading crates ...
+  Downloaded plotters-svg v0.3.7
+  Downloaded same-file v1.0.6
+  Downloaded plotters-backend v0.3.7
+  Downloaded alloca v0.4.0
+  Downloaded ciborium v0.2.2
+  Downloaded ciborium-ll v0.2.2
+  Downloaded walkdir v2.5.0
+  Downloaded tinytemplate v1.2.1
+  Downloaded page_size v0.6.0
+  Downloaded itertools v0.13.0
+  Downloaded oorandom v11.1.5
+  Downloaded criterion-plot v0.8.2
+  Downloaded ciborium-io v0.2.2
+  Downloaded criterion v0.8.2
+  Downloaded regex v1.13.1
+  Downloaded plotters v0.3.7
+  Downloaded cast v0.3.0
+  Downloaded anes v0.1.6
+   Compiling unicode-ident v1.0.24
+   Compiling cfg-if v1.0.4
+   Compiling serde_core v1.0.229
+   Compiling serde v1.0.229
+   Compiling libc v0.2.189
+   Compiling proc-macro2 v1.0.107
+   Compiling memchr v2.8.3
+   Compiling quote v1.0.47
+   Compiling syn v3.0.3
+   Compiling syn v2.0.119
+   Compiling typenum v1.20.1
+   Compiling rand_core v0.10.1
+   Compiling zeroize v1.9.0
+   Compiling shlex v2.0.1
+   Compiling cc v1.4.3
+   Compiling getrandom v0.4.3
+   Compiling hybrid-array v0.4.14
+   Compiling log v0.4.33
+   Compiling simd-adler32 v0.3.10
+   Compiling crossbeam-utils v0.8.22
+   Compiling crypto-common v0.2.2
+   Compiling bitflags v2.13.1
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+   Compiling itoa v1.0.18
+   Compiling num-traits v0.2.19
+   Compiling stable_deref_trait v1.2.1
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+   Compiling pin-project-lite v0.2.17
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+   Compiling strum_macros v0.28.0
+   Compiling block-buffer v0.12.1
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+   Compiling crossbeam-epoch v0.9.20
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+   Compiling smallvec v1.15.2
+   Compiling flate2 v1.1.10
+   Compiling techscript_syntax v2.0.0 (/app/compiler/syntax)
+   Compiling techscript_errors v2.0.0 (/app/compiler/errors)
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+   Compiling zerocopy-derive v0.8.56
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+   Compiling pulp-wasm-simd-flag v0.1.1
+   Compiling libbz2-rs-sys v0.2.5
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+   Compiling new_debug_unreachable v1.0.6
+   Compiling reborrow v0.5.5
+   Compiling azul-simplecss v0.2.1
+   Compiling imgref v1.12.2
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+   Compiling unicode-segmentation v1.13.3
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+   Compiling constant_time_eq v0.4.2
+   Compiling deflate64 v0.1.12
+   Compiling bit_field v0.10.3
+   Compiling pxfm v0.1.30
+   Compiling gl-context-loader v0.1.10
+   Compiling azul-core v0.0.16
+   Compiling zip v8.6.0
+   Compiling exr v1.74.2
+   Compiling moxcms v0.8.1
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+   Compiling stringprep v0.1.5
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+   Compiling async-process v2.5.0
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+   Compiling async-executor v1.14.0
+   Compiling qoi v0.4.1
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+   Compiling cbc v0.2.1
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+   Compiling async-recursion v1.1.1
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+   Compiling iana-time-zone v0.1.65
+   Compiling weezl v0.2.1
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+   Compiling debug_unsafe v0.1.4
+   Compiling xmlwriter v0.1.0
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+   Compiling azul-layout v0.0.16
+   Compiling atoi_simd v0.18.1
+   Compiling chrono v0.4.45
+   Compiling zbus v5.19.0
+   Compiling image v0.25.10
+   Compiling digest v0.10.7
+   Compiling ghash v0.6.0
+   Compiling blowfish v0.10.0
+   Compiling xattr v1.6.1
+   Compiling techscript_runtime v2.0.0 (/app/runtime/runtime)
+   Compiling codepage v0.1.2
+   Compiling quick-xml v0.41.0
+   Compiling hashlink v0.12.1
+   Compiling ctr v0.10.1
+   Compiling aead v0.6.1
+   Compiling filetime v0.2.29
+   Compiling csv-core v0.1.13
+   Compiling fallible-iterator v0.3.0
+   Compiling crc-catalog v2.5.0
+   Compiling cpufeatures v0.2.17
+   Compiling ascii v1.1.0
+   Compiling fallible-streaming-iterator v0.1.9
+   Compiling chunked_transfer v1.5.0
+   Compiling httpdate v1.0.3
+   Compiling fast-float2 v0.2.4
+   Compiling ryu v1.0.23
+   Compiling calamine v0.36.1
+   Compiling csv v1.4.0
+   Compiling tiny_http v0.12.0
+   Compiling rusqlite v0.40.2
+   Compiling sha-1 v0.10.1
+   Compiling crc v3.4.0
+   Compiling tar v0.4.46
+   Compiling aes-gcm v0.11.1
+   Compiling bcrypt v0.19.3
+   Compiling notify-rust v4.18.1
+   Compiling qrcode v0.14.1
+   Compiling quick-xml v0.42.0
+   Compiling md5 v0.8.1
+   Compiling logos-codegen v0.16.1
+   Compiling techscript_module_resolver v2.0.0 (/app/compiler/module_resolver)
+   Compiling techscript_parser v2.0.0 (/app/compiler/parser)
+   Compiling utf8parse v0.2.2
+   Compiling anstyle-parse v1.0.0
+   Compiling is_terminal_polyfill v1.70.2
+   Compiling colorchoice v1.0.5
+   Compiling anstyle v1.0.14
+   Compiling anstyle-query v1.1.5
+   Compiling anstream v1.0.0
+   Compiling logos-derive v0.16.1
+   Compiling strsim v0.11.1
+   Compiling logos v0.16.1
+   Compiling clap_lex v1.1.0
+   Compiling techscript_lexer v2.0.0 (/app/compiler/lexer)
+   Compiling clap_builder v4.6.7
+   Compiling clap_derive v4.6.7
+   Compiling bincode v3.0.0
+error: https://xkcd.com/2347/
+ --> /home/jules/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/bincode-3.0.0/src/lib.rs:1:1
+  |
+1 | compile_error!("https://xkcd.com/2347/");
+  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: could not compile `bincode` (lib) due to 1 previous error
+warning: build failed, waiting for other jobs to finish...