diff --git a/package.json b/package.json
index 8fbd136..097846b 100644
--- a/package.json
+++ b/package.json
@@ -17,7 +17,7 @@
     "build:electron:mac": "pnpm build && electron-builder --mac dmg --arm64 --x64 && electron-builder --mac pkg --arm64 && electron-builder --mac pkg --x64",
     "build:linux": "pnpm run cleanBuild && pnpm run build:server && pnpm run build:linux-bundle && pnpm run build:linux-pkg && pnpm run build:linux-packages",
     "build:linux-bundle": "node scripts/build-linux-bundle.mjs",
-    "build:linux-pkg": "shx mkdir -p app_dist/linux && pnpm exec pkg build/pkg-entry.cjs --config package.json --targets node18-linux-x64 --public-packages \"pdf-to-img,pdfjs-dist,sharp,canvas,@img/*,@napi-rs/*\" --output app_dist/linux/farmcontrol-server",
+    "build:linux-pkg": "shx mkdir -p app_dist/linux && pnpm exec pkg build/pkg-entry.cjs --config package.json --targets node18-linux-x64 --no-bytecode --public-packages \"pdf-to-img,pdfjs-dist,sharp,canvas,@img/*,@napi-rs/*\" --output app_dist/linux/farmcontrol-server",
     "build:linux-packages": "bash scripts/build-linux-packages.sh",
     "cleanBuild": "rimraf build"
   },
diff --git a/src/pdfUtils.js b/src/pdfUtils.js
index 56cbf6e..343feb3 100644
--- a/src/pdfUtils.js
+++ b/src/pdfUtils.js
@@ -7,17 +7,36 @@ import { pathToFileURL } from 'node:url'
 
 const require = createRequire(import.meta.url)
 
-// Bare dynamic import() fails in pkg snapshots with "Invalid host defined options".
+// Dynamic import() from pkg snapshot bytecode throws "Invalid host defined options"
+// (nodejs/node#43663). Use require() for CJS packages in pkg; ESM packages need
+// --no-bytecode on the pkg build so file-URL import() works.
 async function importPackage(name) {
   const packagePath = require.resolve(name)
+
+  if (typeof process.pkg !== 'undefined') {
+    try {
+      return require(packagePath)
+    } catch (error) {
+      if (error?.code !== 'ERR_REQUIRE_ESM') {
+        throw error
+      }
+    }
+  }
+
   return import(pathToFileURL(packagePath).href)
 }
 
+function resolveDefault(module) {
+  return module?.default ?? module
+}
+
 export async function convertPDFToImage(pdfInput, options = {}) {
-  const [{ pdf }, sharp] = await Promise.all([
+  const [pdfToImgModule, sharpModule] = await Promise.all([
     importPackage('pdf-to-img'),
     importPackage('sharp')
   ])
+  const { pdf } = pdfToImgModule
+  const sharp = resolveDefault(sharpModule)
 
   try {
     const { width, height, page_numbers, scale = 2, ...pdfOnlyOptions } =
@@ -43,7 +62,7 @@ export async function convertPDFToImage(pdfInput, options = {}) {
           const resizeOptions = {}
           if (width) resizeOptions.width = width
           if (height) resizeOptions.height = height
-          image = await sharp.default(image).resize(resizeOptions).toBuffer()
+          image = await sharp(image).resize(resizeOptions).toBuffer()
         }
 
         outputImages.push(image)
@@ -56,7 +75,7 @@ export async function convertPDFToImage(pdfInput, options = {}) {
           const resizeOptions = {}
           if (width) resizeOptions.width = width
           if (height) resizeOptions.height = height
-          processedImage = await sharp.default(image)
+          processedImage = await sharp(image)
             .resize(resizeOptions)
             .toBuffer()
         }