diff --git a/packages/edge-bundler/deno/extract.ts b/packages/edge-bundler/deno/extract.ts
deleted file mode 100644
index 873a72464f..0000000000
--- a/packages/edge-bundler/deno/extract.ts
+++ /dev/null
@@ -1,7 +0,0 @@
-import { loadESZIP } from 'https://deno.land/x/eszip@v0.55.2/eszip.ts'
-
-const [functionPath, destPath] = Deno.args
-
-const eszip = await loadESZIP(functionPath)
-
-await eszip.extract(destPath)
diff --git a/packages/edge-bundler/node/bridge.test.ts b/packages/edge-bundler/node/bridge.test.ts
index 8e51893be1..4315231a14 100644
--- a/packages/edge-bundler/node/bridge.test.ts
+++ b/packages/edge-bundler/node/bridge.test.ts
@@ -9,14 +9,14 @@ import semver from 'semver'
 import tmp, { DirectoryResult } from 'tmp-promise'
 import { test, expect } from 'vitest'
 
-import { DenoBridge, DENO_VERSION_RANGE } from './bridge.js'
+import { DenoBridge, LEGACY_DENO_VERSION_RANGE } from './bridge.js'
 import { getPlatformTarget } from './platform.js'
 
 const require = createRequire(import.meta.url)
 const archiver = require('archiver')
 
 const getMockDenoBridge = function (tmpDir: DirectoryResult, mockBinaryOutput: string) {
-  const latestVersion = semver.minVersion(DENO_VERSION_RANGE)?.version ?? ''
+  const latestVersion = semver.minVersion(LEGACY_DENO_VERSION_RANGE)?.version ?? ''
   const data = new PassThrough()
   const archive = archiver('zip', { zlib: { level: 9 } })
 
@@ -139,7 +139,7 @@ test('Does inherit environment variables if `extendEnv` is not set', async () =>
 
 test('Provides actionable error message when downloaded binary cannot be executed', async () => {
   const tmpDir = await tmp.dir()
-  const latestVersion = semver.minVersion(DENO_VERSION_RANGE)?.version ?? ''
+  const latestVersion = semver.minVersion(LEGACY_DENO_VERSION_RANGE)?.version ?? ''
   const data = new PassThrough()
   const archive = archiver('zip', { zlib: { level: 9 } })
 
diff --git a/packages/edge-bundler/node/bridge.ts b/packages/edge-bundler/node/bridge.ts
index d75447abd0..3dcea43ee5 100644
--- a/packages/edge-bundler/node/bridge.ts
+++ b/packages/edge-bundler/node/bridge.ts
@@ -14,12 +14,12 @@ import { getBinaryExtension } from './platform.js'
 
 const DENO_VERSION_FILE = 'version.txt'
 
+export const LEGACY_DENO_VERSION_RANGE = '1.39.0 - 2.2.4'
+
 // When updating DENO_VERSION_RANGE, ensure that the deno version
 // on the netlify/buildbot build image satisfies this range!
 // https://github.com/netlify/buildbot/blob/f9c03c9dcb091d6570e9d0778381560d469e78ad/build-image/noble/Dockerfile#L410
-export const DENO_VERSION_RANGE = '1.39.0 - 2.2.4'
-
-const NEXT_DENO_VERSION_RANGE = '^2.4.2'
+const DENO_VERSION_RANGE = '^2.4.2'
 
 export type OnBeforeDownloadHook = () => void | Promise<void>
 export type OnAfterDownloadHook = (error?: Error) => void | Promise<void>
@@ -75,7 +75,7 @@ export class DenoBridge {
       options.featureFlags?.edge_bundler_generate_tarball ||
       options.featureFlags?.edge_bundler_deno_v2
 
-    this.versionRange = options.versionRange ?? (useNextDeno ? NEXT_DENO_VERSION_RANGE : DENO_VERSION_RANGE)
+    this.versionRange = options.versionRange ?? (useNextDeno ? DENO_VERSION_RANGE : LEGACY_DENO_VERSION_RANGE)
   }
 
   private async downloadBinary() {
diff --git a/packages/edge-bundler/node/bundler.test.ts b/packages/edge-bundler/node/bundler.test.ts
index 0807337a6a..d502e23361 100644
--- a/packages/edge-bundler/node/bundler.test.ts
+++ b/packages/edge-bundler/node/bundler.test.ts
@@ -626,8 +626,8 @@ test('Loads JSON modules with `with` attribute', async () => {
   await rm(vendorDirectory.path, { force: true, recursive: true })
 })
 
-test('Emits a system log when import assertions are used', async () => {
-  const { basePath, cleanup, distPath } = await useFixture('with_import_assert')
+test('Is backwards compatible with Deno 1.x', async () => {
+  const { basePath, cleanup, distPath } = await useFixture('with_deno_1x_features')
   const sourceDirectory = join(basePath, 'functions')
   const vendorDirectory = await tmp.dir()
   const systemLogger = vi.fn()
@@ -643,18 +643,45 @@ test('Emits a system log when import assertions are used', async () => {
 
   const manifestFile = await readFile(resolve(distPath, 'manifest.json'), 'utf8')
   const manifest = JSON.parse(manifestFile)
-  const bundlePath = join(distPath, manifest.bundles[0].asset)
-  const { func1 } = await runESZIP(bundlePath, vendorDirectory.path)
 
-  expect(func1).toBe(`{"foo":"bar"}`)
   expect(systemLogger).toHaveBeenCalledWith(
     `Edge function uses import assertions: ${join(sourceDirectory, 'func1.ts')}`,
   )
   expect(manifest.routes[0]).toEqual({
     function: 'func1',
-    pattern: '^/with-import-assert/?$',
+    pattern: '^/with-import-assert-ts/?$',
+    excluded_patterns: [],
+    path: '/with-import-assert-ts',
+  })
+
+  expect(systemLogger).toHaveBeenCalledWith(
+    `Edge function uses import assertions: ${join(sourceDirectory, 'func2.js')}`,
+  )
+  expect(manifest.routes[1]).toEqual({
+    function: 'func2',
+    pattern: '^/with-import-assert-js/?$',
+    excluded_patterns: [],
+    path: '/with-import-assert-js',
+  })
+
+  expect(systemLogger).toHaveBeenCalledWith(
+    `Edge function uses the window global: ${join(sourceDirectory, 'func3.ts')}`,
+  )
+  expect(manifest.routes[2]).toEqual({
+    function: 'func3',
+    pattern: '^/with-window-global-ts/?$',
+    excluded_patterns: [],
+    path: '/with-window-global-ts',
+  })
+
+  expect(systemLogger).toHaveBeenCalledWith(
+    `Edge function uses the window global: ${join(sourceDirectory, 'func4.js')}`,
+  )
+  expect(manifest.routes[3]).toEqual({
+    function: 'func4',
+    pattern: '^/with-window-global-js/?$',
     excluded_patterns: [],
-    path: '/with-import-assert',
+    path: '/with-window-global-js',
   })
 
   await cleanup()
diff --git a/packages/edge-bundler/node/bundler.ts b/packages/edge-bundler/node/bundler.ts
index beb509932c..49abb0175c 100644
--- a/packages/edge-bundler/node/bundler.ts
+++ b/packages/edge-bundler/node/bundler.ts
@@ -1,12 +1,18 @@
 import { promises as fs } from 'fs'
-import { join, relative } from 'path'
+import { join } from 'path'
 
 import commonPathPrefix from 'common-path-prefix'
 import { v4 as uuidv4 } from 'uuid'
 
 import { importMapSpecifier } from '../shared/consts.js'
 
-import { DenoBridge, DenoOptions, OnAfterDownloadHook, OnBeforeDownloadHook } from './bridge.js'
+import {
+  DenoBridge,
+  DenoOptions,
+  OnAfterDownloadHook,
+  OnBeforeDownloadHook,
+  LEGACY_DENO_VERSION_RANGE,
+} from './bridge.js'
 import type { Bundle } from './bundle.js'
 import { FunctionConfig, getFunctionConfig } from './config.js'
 import { Declaration, mergeDeclarations } from './declaration.js'
@@ -14,7 +20,7 @@ import { load as loadDeployConfig } from './deploy_config.js'
 import { EdgeFunction } from './edge_function.js'
 import { FeatureFlags, getFlags } from './feature_flags.js'
 import { findFunctions } from './finder.js'
-import { bundle as bundleESZIP, extension as eszipExtension, extract as extractESZIP } from './formats/eszip.js'
+import { bundle as bundleESZIP } from './formats/eszip.js'
 import { bundle as bundleTarball } from './formats/tarball.js'
 import { ImportMap } from './import_map.js'
 import { getLogger, LogFunction, Logger } from './logger.js'
@@ -22,7 +28,7 @@ import { writeManifest } from './manifest.js'
 import { vendorNPMSpecifiers } from './npm_dependencies.js'
 import { ensureLatestTypes } from './types.js'
 import { nonNullable } from './utils/non_nullable.js'
-import { BundleError } from './bundle_error.js'
+import { getPathInHome } from './home_path.js'
 
 export interface BundleOptions {
   basePath?: string
@@ -172,15 +178,11 @@ export const bundle = async (
   // The final file name of the bundles contains a SHA256 hash of the contents,
   // which we can only compute now that the files have been generated. So let's
   // rename the bundles to their permanent names.
-  const bundlePaths = await createFinalBundles(bundles, distDirectory, buildID)
-  const eszipPath = bundlePaths.find((path) => path.endsWith(eszipExtension))
+  await createFinalBundles(bundles, distDirectory, buildID)
 
   const { internalFunctions: internalFunctionsWithConfig, userFunctions: userFunctionsWithConfig } =
     await getFunctionConfigs({
-      basePath,
       deno,
-      eszipPath,
-      featureFlags,
       importMap,
       internalFunctions,
       log: logger,
@@ -224,10 +226,7 @@ export const bundle = async (
 }
 
 interface GetFunctionConfigsOptions {
-  basePath: string
   deno: DenoBridge
-  eszipPath?: string
-  featureFlags?: FeatureFlags
   importMap: ImportMap
   internalFunctions: EdgeFunction[]
   log: Logger
@@ -235,70 +234,57 @@ interface GetFunctionConfigsOptions {
 }
 
 const getFunctionConfigs = async ({
-  basePath,
   deno,
-  eszipPath,
-  featureFlags,
   importMap,
   log,
   internalFunctions,
   userFunctions,
 }: GetFunctionConfigsOptions) => {
-  try {
-    const internalConfigPromises = internalFunctions.map(
-      async (func) => [func.name, await getFunctionConfig({ functionPath: func.path, importMap, deno, log })] as const,
-    )
-    const userConfigPromises = userFunctions.map(
-      async (func) => [func.name, await getFunctionConfig({ functionPath: func.path, importMap, deno, log })] as const,
-    )
-
-    // Creating a hash of function names to configuration objects.
-    const internalFunctionsWithConfig = Object.fromEntries(await Promise.all(internalConfigPromises))
-    const userFunctionsWithConfig = Object.fromEntries(await Promise.all(userConfigPromises))
-
-    return {
-      internalFunctions: internalFunctionsWithConfig,
-      userFunctions: userFunctionsWithConfig,
-    }
-  } catch (err) {
-    if (!(err instanceof Error && err.cause === 'IMPORT_ASSERT') || !eszipPath || !featureFlags?.edge_bundler_deno_v2) {
-      throw err
-    }
+  const functions = [...internalFunctions, ...userFunctions]
+  const results = await Promise.allSettled(
+    functions.map(async (func) => {
+      return [func.name, await getFunctionConfig({ functionPath: func.path, importMap, deno, log })] as const
+    }),
+  )
+  const legacyDeno = new DenoBridge({
+    cacheDirectory: getPathInHome('deno-cli-v1'),
+    useGlobal: false,
+    versionRange: LEGACY_DENO_VERSION_RANGE,
+  })
 
-    log.user(
-      'WARNING: Import assertions are deprecated and will be removed soon. Refer to https://ntl.fyi/import-assert for more information.',
-    )
+  for (let i = 0; i < results.length; i++) {
+    const result = results[i]
+    const func = functions[i]
+
+    // We offer support for some features of Deno 1.x that have been removed
+    // from 2.x, such as import assertions and the `window` global. When we
+    // see that we failed to extract a config due to those edge cases, re-run
+    // the script with Deno 1.x so we can extract the config.
+    if (
+      result.status === 'rejected' &&
+      result.reason instanceof Error &&
+      (result.reason.cause === 'IMPORT_ASSERT' || result.reason.cause === 'WINDOW_GLOBAL')
+    ) {
+      try {
+        const fallbackConfig = await getFunctionConfig({ functionPath: func.path, importMap, deno: legacyDeno, log })
 
-    try {
-      // We failed to extract the configuration because there is an import assert
-      // in the function code, a deprecated feature that we used to support with
-      // Deno 1.x. To avoid a breaking change, we treat this error as a special
-      // case, using the generated ESZIP to extract the configuration. This works
-      // because import asserts are transpiled to import attributes.
-      const extractedESZIP = await extractESZIP(deno, eszipPath)
-      const configs = await Promise.all(
-        [...internalFunctions, ...userFunctions].map(async (func) => {
-          const relativePath = relative(basePath, func.path)
-          const functionPath = join(extractedESZIP.path, relativePath)
+        results[i] = { status: 'fulfilled', value: [func.name, fallbackConfig] }
+      } catch {
+        throw result.reason
+      }
+    }
+  }
 
-          return [func.name, await getFunctionConfig({ functionPath, importMap, deno, log })] as const
-        }),
-      )
+  const failure = results.find((result) => result.status === 'rejected')
+  if (failure) {
+    throw failure.reason
+  }
 
-      await extractedESZIP.cleanup()
+  const configs = results.map((config) => (config as PromiseFulfilledResult<[string, FunctionConfig]>).value)
 
-      return {
-        internalFunctions: Object.fromEntries(configs.slice(0, internalFunctions.length)),
-        userFunctions: Object.fromEntries(configs.slice(internalFunctions.length)),
-      }
-    } catch (err) {
-      throw new BundleError(
-        new Error(
-          'An error occurred while building an edge function that uses an import assertion. Refer to https://ntl.fyi/import-assert for more information.',
-        ),
-        { cause: err },
-      )
-    }
+  return {
+    internalFunctions: Object.fromEntries(configs.slice(0, internalFunctions.length)),
+    userFunctions: Object.fromEntries(configs.slice(internalFunctions.length)),
   }
 }
 
diff --git a/packages/edge-bundler/node/config.ts b/packages/edge-bundler/node/config.ts
index b73fe3fc75..7283f993af 100644
--- a/packages/edge-bundler/node/config.ts
+++ b/packages/edge-bundler/node/config.ts
@@ -157,12 +157,21 @@ export const getFunctionConfig = async ({
 const handleConfigError = (functionPath: string, exitCode: number, stderr: string, log: Logger) => {
   let cause: string | Error | undefined
 
-  if (stderr.includes('Import assertions are deprecated')) {
+  if (
+    stderr.includes('Import assertions are deprecated') ||
+    stderr.includes(`SyntaxError: Unexpected identifier 'assert'`)
+  ) {
     log.system(`Edge function uses import assertions: ${functionPath}`)
 
     cause = 'IMPORT_ASSERT'
   }
 
+  if (stderr.includes('ReferenceError: window is not defined')) {
+    log.system(`Edge function uses the window global: ${functionPath}`)
+
+    cause = 'WINDOW_GLOBAL'
+  }
+
   switch (exitCode) {
     case ConfigExitCode.ImportError:
       log.user(stderr)
diff --git a/packages/edge-bundler/node/formats/eszip.ts b/packages/edge-bundler/node/formats/eszip.ts
index 66351e8c6b..7457d815af 100644
--- a/packages/edge-bundler/node/formats/eszip.ts
+++ b/packages/edge-bundler/node/formats/eszip.ts
@@ -1,8 +1,6 @@
 import { join } from 'path'
 import { pathToFileURL } from 'url'
 
-import tmp from 'tmp-promise'
-
 import { virtualRoot, virtualVendorRoot } from '../../shared/consts.js'
 import type { WriteStage2Options } from '../../shared/stage2.js'
 import { DenoBridge } from '../bridge.js'
@@ -88,16 +86,3 @@ const getESZIPPaths = () => {
     importMap: join(denoPath, 'vendor', 'import_map.json'),
   }
 }
-
-export const extract = async (deno: DenoBridge, functionPath: string) => {
-  const tmpDir = await tmp.dir({ unsafeCleanup: true })
-  const { extractor, importMap } = getESZIPPaths()
-  const flags = ['--allow-all', '--no-config', '--no-lock', `--import-map=${importMap}`, '--quiet']
-
-  await deno.run(['run', ...flags, extractor, functionPath, tmpDir.path], { pipeOutput: true })
-
-  return {
-    cleanup: tmpDir.cleanup,
-    path: join(tmpDir.path, 'source', 'root'),
-  }
-}
diff --git a/packages/edge-bundler/node/main.test.ts b/packages/edge-bundler/node/main.test.ts
index b530bc6b1f..78cff9e762 100644
--- a/packages/edge-bundler/node/main.test.ts
+++ b/packages/edge-bundler/node/main.test.ts
@@ -9,14 +9,14 @@ import semver from 'semver'
 import tmp from 'tmp-promise'
 import { test, expect, vi } from 'vitest'
 
-import { DenoBridge, DENO_VERSION_RANGE } from './bridge.js'
+import { DenoBridge, LEGACY_DENO_VERSION_RANGE } from './bridge.js'
 import { getPlatformTarget } from './platform.js'
 
 const require = createRequire(import.meta.url)
 const archiver = require('archiver')
 
 test('Downloads the Deno CLI on demand and caches it for subsequent calls', async () => {
-  const latestVersion = semver.minVersion(DENO_VERSION_RANGE)?.version ?? ''
+  const latestVersion = semver.minVersion(LEGACY_DENO_VERSION_RANGE)?.version ?? ''
   const mockBinaryOutput = `#!/usr/bin/env sh\n\necho "deno ${latestVersion}"`
   const data = new PassThrough()
   const archive = archiver('zip', { zlib: { level: 9 } })
diff --git a/packages/edge-bundler/package.json b/packages/edge-bundler/package.json
index cb04591cac..14d0521467 100644
--- a/packages/edge-bundler/package.json
+++ b/packages/edge-bundler/package.json
@@ -9,6 +9,7 @@
     "deno/**",
     "!deno/**/*.test.ts",
     "dist/**/*.js",
+    "!dist/**/*.test.js",
     "dist/**/*.d.ts",
     "shared/**"
   ],
diff --git a/packages/edge-bundler/test/fixtures/with_import_assert/functions/dict.json b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/dict.json
similarity index 100%
rename from packages/edge-bundler/test/fixtures/with_import_assert/functions/dict.json
rename to packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/dict.json
diff --git a/packages/edge-bundler/test/fixtures/with_import_assert/functions/func1.ts b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func1.ts
similarity index 79%
rename from packages/edge-bundler/test/fixtures/with_import_assert/functions/func1.ts
rename to packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func1.ts
index 552dbf5e8c..4ba28092b4 100644
--- a/packages/edge-bundler/test/fixtures/with_import_assert/functions/func1.ts
+++ b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func1.ts
@@ -4,5 +4,5 @@ import dict from './dict.json' assert { type: "json" }
 export default async () => Response.json(dict)
 
 export const config = {
-  path: "/with-import-assert"
+  path: "/with-import-assert-ts"
 }
diff --git a/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func2.js b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func2.js
new file mode 100644
index 0000000000..b85b5548c5
--- /dev/null
+++ b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func2.js
@@ -0,0 +1,8 @@
+import dict from './dict.json' assert { type: "json" }
+
+
+export default async () => Response.json(dict)
+
+export const config = {
+  path: "/with-import-assert-js"
+}
diff --git a/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func3.ts b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func3.ts
new file mode 100644
index 0000000000..79c03dfa70
--- /dev/null
+++ b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func3.ts
@@ -0,0 +1,7 @@
+window.foo = 1
+
+export default async () => Response.json({})
+
+export const config = {
+  path: "/with-window-global-ts"
+}
diff --git a/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func4.js b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func4.js
new file mode 100644
index 0000000000..df378fc460
--- /dev/null
+++ b/packages/edge-bundler/test/fixtures/with_deno_1x_features/functions/func4.js
@@ -0,0 +1,7 @@
+window.foo = 1
+
+export default async () => Response.json({})
+
+export const config = {
+  path: "/with-window-global-js"
+}