diff --git a/Cargo.lock b/Cargo.lock
index ba55cad908..2faf17d449 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1257,9 +1257,9 @@ dependencies = [
 
 [[package]]
 name = "deno_core"
-version = "0.266.0"
+version = "0.267.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cfbfe65d133be3abefb973f87b601f686666bb05d5521f0fab16d9dd28a5d5cf"
+checksum = "b5dc9aeacf98e78c1d8fa716e35f2e8a960e349f73d6bc485d45e49457d80556"
 dependencies = [
  "anyhow",
  "bincode",
@@ -1714,9 +1714,9 @@ dependencies = [
 
 [[package]]
 name = "deno_ops"
-version = "0.142.0"
+version = "0.143.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f96d7d6806eb726b4feb3092cbdaf887ae412b6e8be7c67617c61dbe8b3f1693"
+checksum = "594aa46152868ee15e104ab3484976a144162694a00c4096174e71b78fdb32c7"
 dependencies = [
  "proc-macro-rules",
  "proc-macro2",
@@ -5600,9 +5600,9 @@ dependencies = [
 
 [[package]]
 name = "serde_v8"
-version = "0.175.0"
+version = "0.176.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dfb0193c9e969f1d7a660a2c5ad7c94bb00146c5f5367607eabb2af78094160f"
+checksum = "25b62c66605745359af254c41af8e6ea2b6124a3698628a7329a6f32698250ee"
 dependencies = [
  "bytes",
  "derive_more",
diff --git a/Cargo.toml b/Cargo.toml
index 6dea7d48e9..b2f6f4fa3c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -43,7 +43,7 @@ repository = "https://github.com/denoland/deno"
 
 [workspace.dependencies]
 deno_ast = { version = "0.34.1", features = ["transpiling"] }
-deno_core = { version = "0.266.0", features = ["snapshot_data_bincode"] }
+deno_core = { version = "0.267.0" }
 
 deno_bench_util = { version = "0.134.0", path = "./bench_util" }
 deno_lockfile = "0.19.0"
diff --git a/bench_util/js_runtime.rs b/bench_util/js_runtime.rs
index 819a6c02bd..a97d8ae501 100644
--- a/bench_util/js_runtime.rs
+++ b/bench_util/js_runtime.rs
@@ -116,7 +116,7 @@ pub fn bench_js_async_with(
 }
 
 async fn inner_async(src: &'static str, runtime: &mut JsRuntime) {
-  runtime.execute_script_static("inner_loop", src).unwrap();
+  runtime.execute_script("inner_loop", src).unwrap();
   runtime
     .run_event_loop(PollEventLoopOptions::default())
     .await
diff --git a/cli/build.rs b/cli/build.rs
index 0a599b03b1..8dc3dcb759 100644
--- a/cli/build.rs
+++ b/cli/build.rs
@@ -276,6 +276,7 @@ mod ts {
           build_libs,
           path_dts,
         )],
+        extension_transpiler: None,
         with_runtime_cb: None,
         skip_op_registration: false,
       },
diff --git a/cli/js.rs b/cli/js.rs
index 552f3842dc..0db132bdbf 100644
--- a/cli/js.rs
+++ b/cli/js.rs
@@ -29,7 +29,7 @@ mod tests {
       ..Default::default()
     });
     js_runtime
-      .execute_script_static(
+      .execute_script(
         "<anon>",
         r#"
       if (!(bootstrap.mainRuntime && bootstrap.workerRuntime)) {
diff --git a/cli/lsp/tsc.rs b/cli/lsp/tsc.rs
index 138640d7fb..ce848c210b 100644
--- a/cli/lsp/tsc.rs
+++ b/cli/lsp/tsc.rs
@@ -4186,7 +4186,7 @@ fn start_tsc(runtime: &mut JsRuntime, debug: bool) -> Result<(), AnyError> {
   let init_config = json!({ "debug": debug });
   let init_src = format!("globalThis.serverInit({init_config});");
 
-  runtime.execute_script(located_script_name!(), init_src.into())?;
+  runtime.execute_script(located_script_name!(), init_src)?;
   Ok(())
 }
 
@@ -4564,7 +4564,7 @@ fn request(
     "globalThis.serverRequest({id}, \"{}\", {});",
     request.method, &request.args
   );
-  runtime.execute_script(located_script_name!(), request_src.into())?;
+  runtime.execute_script(located_script_name!(), request_src)?;
 
   let op_state = runtime.op_state();
   let mut op_state = op_state.borrow_mut();
diff --git a/cli/tsc/mod.rs b/cli/tsc/mod.rs
index e2e11e440e..4961d1ed94 100644
--- a/cli/tsc/mod.rs
+++ b/cli/tsc/mod.rs
@@ -848,7 +848,7 @@ pub fn exec(request: Request) -> Result<Response, AnyError> {
     "rootNames": root_names,
     "localOnly": request.check_mode == TypeCheckMode::Local,
   });
-  let exec_source = format!("globalThis.exec({request_value})").into();
+  let exec_source = format!("globalThis.exec({request_value})");
 
   let mut runtime = JsRuntime::new(RuntimeOptions {
     startup_snapshot: Some(compiler_snapshot()),
@@ -1007,7 +1007,7 @@ mod tests {
       ..Default::default()
     });
     js_runtime
-      .execute_script_static(
+      .execute_script(
         "<anon>",
         r#"
       if (!(globalThis.exec)) {
diff --git a/cli/worker.rs b/cli/worker.rs
index 302303f286..47658e5945 100644
--- a/cli/worker.rs
+++ b/cli/worker.rs
@@ -397,10 +397,7 @@ impl CliMainWorker {
     name: &'static str,
     source_code: &'static str,
   ) -> Result<v8::Global<v8::Value>, AnyError> {
-    self
-      .worker
-      .js_runtime
-      .execute_script_static(name, source_code)
+    self.worker.js_runtime.execute_script(name, source_code)
   }
 }
 
@@ -656,9 +653,9 @@ impl CliMainWorkerFactory {
     if self.shared.subcommand.needs_test() {
       macro_rules! test_file {
         ($($file:literal),*) => {
-          $(worker.js_runtime.lazy_load_es_module_from_code(
+          $(worker.js_runtime.lazy_load_es_module_with_code(
             concat!("ext:cli/", $file),
-            deno_core::FastString::StaticAscii(include_str!(concat!("js/", $file))),
+            deno_core::ascii_str_include!(concat!("js/", $file)),
           )?;)*
         }
       }
diff --git a/ext/node/lib.rs b/ext/node/lib.rs
index 98b927ba83..40c9e70199 100644
--- a/ext/node/lib.rs
+++ b/ext/node/lib.rs
@@ -636,8 +636,7 @@ pub fn load_cjs_module(
     main = main,
     module = escape_for_single_quote_string(module),
     inspect_brk = inspect_brk,
-  )
-  .into();
+  );
 
   js_runtime.execute_script(located_script_name!(), source_code)?;
   Ok(())
diff --git a/runtime/shared.rs b/runtime/shared.rs
index 04fcdcfdb7..fc91be1453 100644
--- a/runtime/shared.rs
+++ b/runtime/shared.rs
@@ -7,8 +7,9 @@ use deno_ast::SourceTextInfo;
 use deno_core::error::AnyError;
 use deno_core::extension;
 use deno_core::Extension;
-use deno_core::ExtensionFileSource;
-use deno_core::ExtensionFileSourceCode;
+use deno_core::ModuleCodeString;
+use deno_core::ModuleName;
+use deno_core::SourceMapData;
 use std::path::Path;
 
 extension!(runtime,
@@ -56,36 +57,38 @@ extension!(runtime,
   customizer = |ext: &mut Extension| {
     #[cfg(not(feature = "exclude_runtime_main_js"))]
     {
-      ext.esm_files.to_mut().push(ExtensionFileSource::new("ext:runtime_main/js/99_main.js", include_str!("./js/99_main.js")));
+      use deno_core::ascii_str_include;
+      use deno_core::ExtensionFileSource;
+      ext.esm_files.to_mut().push(ExtensionFileSource::new("ext:runtime_main/js/99_main.js", ascii_str_include!("./js/99_main.js")));
       ext.esm_entry_point = Some("ext:runtime_main/js/99_main.js");
     }
   }
 );
 
 pub fn maybe_transpile_source(
-  source: &mut ExtensionFileSource,
-) -> Result<(), AnyError> {
+  name: ModuleName,
+  source: ModuleCodeString,
+) -> Result<(ModuleCodeString, Option<SourceMapData>), AnyError> {
   // Always transpile `node:` built-in modules, since they might be TypeScript.
-  let media_type = if source.specifier.starts_with("node:") {
+  let media_type = if name.starts_with("node:") {
     MediaType::TypeScript
   } else {
-    MediaType::from_path(Path::new(&source.specifier))
+    MediaType::from_path(Path::new(&name))
   };
 
   match media_type {
     MediaType::TypeScript => {}
-    MediaType::JavaScript => return Ok(()),
-    MediaType::Mjs => return Ok(()),
+    MediaType::JavaScript => return Ok((source, None)),
+    MediaType::Mjs => return Ok((source, None)),
     _ => panic!(
       "Unsupported media type for snapshotting {media_type:?} for file {}",
-      source.specifier
+      name
     ),
   }
-  let code = source.load()?;
 
   let parsed = deno_ast::parse_module(ParseParams {
-    specifier: deno_core::url::Url::parse(source.specifier).unwrap(),
-    text_info: SourceTextInfo::from_string(code.as_str().to_owned()),
+    specifier: deno_core::url::Url::parse(&name).unwrap(),
+    text_info: SourceTextInfo::from_string(source.as_str().to_owned()),
     media_type,
     capture_tokens: false,
     scope_analysis: false,
@@ -97,7 +100,5 @@ pub fn maybe_transpile_source(
     ..Default::default()
   })?;
 
-  source.code =
-    ExtensionFileSourceCode::Computed(transpiled_source.text.into());
-  Ok(())
+  Ok((transpiled_source.text.into(), None))
 }
diff --git a/runtime/snapshot.rs b/runtime/snapshot.rs
index e48af43ff7..edfef39c23 100644
--- a/runtime/snapshot.rs
+++ b/runtime/snapshot.rs
@@ -13,6 +13,7 @@ use deno_http::DefaultHttpPropertyExtractor;
 use std::io::Write;
 use std::path::Path;
 use std::path::PathBuf;
+use std::rc::Rc;
 use std::sync::Arc;
 
 #[derive(Clone)]
@@ -204,7 +205,7 @@ pub fn create_runtime_snapshot(
   // NOTE(bartlomieju): ordering is important here, keep it in sync with
   // `runtime/worker.rs`, `runtime/web_worker.rs` and `runtime/snapshot.rs`!
   let fs = std::sync::Arc::new(deno_fs::RealFs);
-  let mut extensions: Vec<Extension> = vec![
+  let extensions: Vec<Extension> = vec![
     deno_webidl::deno_webidl::init_ops_and_esm(),
     deno_console::deno_console::init_ops_and_esm(),
     deno_url::deno_url::init_ops_and_esm(),
@@ -257,20 +258,14 @@ pub fn create_runtime_snapshot(
     ops::web_worker::deno_web_worker::init_ops(),
   ];
 
-  for extension in &mut extensions {
-    for source in extension.esm_files.to_mut() {
-      maybe_transpile_source(source).unwrap();
-    }
-    for source in extension.js_files.to_mut() {
-      maybe_transpile_source(source).unwrap();
-    }
-  }
-
   let output = create_snapshot(
     CreateSnapshotOptions {
       cargo_manifest_dir: env!("CARGO_MANIFEST_DIR"),
       startup_snapshot: None,
       extensions,
+      extension_transpiler: Some(Rc::new(|specifier, source| {
+        maybe_transpile_source(specifier, source)
+      })),
       with_runtime_cb: Some(Box::new(|rt| {
         let isolate = rt.v8_isolate();
         let scope = &mut v8::HandleScope::new(isolate);
diff --git a/runtime/web_worker.rs b/runtime/web_worker.rs
index 97b855c567..6571da6c26 100644
--- a/runtime/web_worker.rs
+++ b/runtime/web_worker.rs
@@ -2,6 +2,7 @@
 use crate::inspector_server::InspectorServer;
 use crate::ops;
 use crate::permissions::PermissionsContainer;
+use crate::shared::maybe_transpile_source;
 use crate::shared::runtime;
 use crate::tokio_util::create_and_run_current_thread;
 use crate::worker::import_meta_resolve_callback;
@@ -498,16 +499,6 @@ impl WebWorker {
         extension.esm_files = std::borrow::Cow::Borrowed(&[]);
         extension.esm_entry_point = None;
       }
-      #[cfg(not(feature = "only_snapshotted_js_sources"))]
-      {
-        use crate::shared::maybe_transpile_source;
-        for source in extension.esm_files.to_mut() {
-          maybe_transpile_source(source).unwrap();
-        }
-        for source in extension.js_files.to_mut() {
-          maybe_transpile_source(source).unwrap();
-        }
-      }
     }
 
     extensions.extend(std::mem::take(&mut options.extensions));
@@ -535,6 +526,9 @@ impl WebWorker {
       shared_array_buffer_store: options.shared_array_buffer_store.clone(),
       compiled_wasm_module_store: options.compiled_wasm_module_store.clone(),
       extensions,
+      extension_transpiler: Some(Rc::new(|specifier, source| {
+        maybe_transpile_source(specifier, source)
+      })),
       inspector: options.maybe_inspector_server.is_some(),
       feature_checker: Some(options.feature_checker.clone()),
       op_metrics_factory_fn,
@@ -664,10 +658,7 @@ impl WebWorker {
     &mut self,
     module_specifier: &ModuleSpecifier,
   ) -> Result<ModuleId, AnyError> {
-    self
-      .js_runtime
-      .load_main_module(module_specifier, None)
-      .await
+    self.js_runtime.load_main_es_module(module_specifier).await
   }
 
   /// Loads and instantiates specified JavaScript module as "side" module.
@@ -675,10 +666,7 @@ impl WebWorker {
     &mut self,
     module_specifier: &ModuleSpecifier,
   ) -> Result<ModuleId, AnyError> {
-    self
-      .js_runtime
-      .load_side_module(module_specifier, None)
-      .await
+    self.js_runtime.load_side_es_module(module_specifier).await
   }
 
   /// Loads, instantiates and executes specified JavaScript module.
diff --git a/runtime/worker.rs b/runtime/worker.rs
index d19e520c9b..ab3e5fa875 100644
--- a/runtime/worker.rs
+++ b/runtime/worker.rs
@@ -45,6 +45,7 @@ use log::debug;
 use crate::inspector_server::InspectorServer;
 use crate::ops;
 use crate::permissions::PermissionsContainer;
+use crate::shared::maybe_transpile_source;
 use crate::shared::runtime;
 use crate::BootstrapOptions;
 
@@ -445,16 +446,6 @@ impl MainWorker {
         extension.esm_files = std::borrow::Cow::Borrowed(&[]);
         extension.esm_entry_point = None;
       }
-      #[cfg(not(feature = "only_snapshotted_js_sources"))]
-      {
-        use crate::shared::maybe_transpile_source;
-        for source in extension.esm_files.to_mut() {
-          maybe_transpile_source(source).unwrap();
-        }
-        for source in extension.js_files.to_mut() {
-          maybe_transpile_source(source).unwrap();
-        }
-      }
     }
 
     extensions.extend(std::mem::take(&mut options.extensions));
@@ -481,6 +472,9 @@ impl MainWorker {
       shared_array_buffer_store: options.shared_array_buffer_store.clone(),
       compiled_wasm_module_store: options.compiled_wasm_module_store.clone(),
       extensions,
+      extension_transpiler: Some(Rc::new(|specifier, source| {
+        maybe_transpile_source(specifier, source)
+      })),
       inspector: options.maybe_inspector_server.is_some(),
       is_main: true,
       feature_checker: Some(options.feature_checker.clone()),
@@ -579,10 +573,7 @@ impl MainWorker {
     &mut self,
     module_specifier: &ModuleSpecifier,
   ) -> Result<ModuleId, AnyError> {
-    self
-      .js_runtime
-      .load_main_module(module_specifier, None)
-      .await
+    self.js_runtime.load_main_es_module(module_specifier).await
   }
 
   /// Loads and instantiates specified JavaScript module as "side" module.
@@ -590,10 +581,7 @@ impl MainWorker {
     &mut self,
     module_specifier: &ModuleSpecifier,
   ) -> Result<ModuleId, AnyError> {
-    self
-      .js_runtime
-      .load_side_module(module_specifier, None)
-      .await
+    self.js_runtime.load_side_es_module(module_specifier).await
   }
 
   /// Executes specified JavaScript module.