diff --git a/apps/jscad-web/src_bundle/bundle.worker.js b/apps/jscad-web/src_bundle/bundle.worker.js
index 2913a2f..81a7201 100644
--- a/apps/jscad-web/src_bundle/bundle.worker.js
+++ b/apps/jscad-web/src_bundle/bundle.worker.js
@@ -29,21 +29,19 @@ const exportData = ({format, options={}})=>{
   return withTransferable({ data }, data.filter(v=>typeof v !== 'string'))
 }
 
-const importData = (url, readFile, base, root, moduleBase)=>{
-  try {    
-    const jscad_io = require('./bundle.jscad_io.js', null, readFileWeb)
-    let idx = url.lastIndexOf('/')
-    let filename = url.substring(idx+1)
-    idx = filename.lastIndexOf('.')
-    let ext = filename.substring(idx+1)
-    let deserializer = jscad_io.deserializers[ext]
-    let file = readFile(url,{output:ext === 'stl' ? 'bin':'text'})
-
-    if(deserializer) return deserializer({output:'geometry', filename}, file)
-    throw new Error('unsupportd format in '+url)
-  } catch (error) {
-    console.error(error)
-    throw error
+const importData = {
+  isBinaryExt: ext=>ext === 'stl' ? 'bin':'text',
+  deserialize: ({url, filename, ext}, fileContent)=>{
+    try {
+      const jscad_io = require('./bundle.jscad_io.js', null, readFileWeb)
+      let deserializer = jscad_io.deserializers[ext]
+
+      if(deserializer) return deserializer({output:'geometry', filename}, fileContent)
+      throw new Error('unsupportd format in '+url)
+    } catch (error) {
+      console.error(error)
+      throw error
+    }
   }
 }
 
diff --git a/apps/jscad-web/static/test.file.js b/apps/jscad-web/static/test.file.js
new file mode 100644
index 0000000..e69abb3
--- /dev/null
+++ b/apps/jscad-web/static/test.file.js
@@ -0,0 +1,9 @@
+import * as jscad from '@jscad/modeling'
+
+export const main =({// @jscad-params
+  mesh,// {type:"file"}
+  check=false,
+})=>{  
+  return mesh ? mesh : jscad.primitives.sphere()
+
+}
diff --git a/packages/fs-provider/fs-provider.js b/packages/fs-provider/fs-provider.js
index f2339de..45c2736 100644
--- a/packages/fs-provider/fs-provider.js
+++ b/packages/fs-provider/fs-provider.js
@@ -20,7 +20,13 @@ export * from './src/FileEntry.js'
  * @returns {Array<string>}
  */
 export const splitPath = path => (typeof path === 'string' ? path.split('/').filter(p => p && p !== '.') : path)
-
+export function extractPathInfo(url){
+  let idx = url.lastIndexOf('/')
+  let filename = url.substring(idx+1)
+  idx = filename.lastIndexOf('.')
+  let ext = filename.substring(idx+1)
+  return {url, filename, ext}
+}
 export const getFile = async (path, sw) => {
   let arr = splitPath(path)
   let match = await findFileInRoots(sw.roots, arr)
@@ -233,7 +239,6 @@ export async function fileDropped(sw, files) {
   let time = Date.now()
   const preLoad = ['/' + sw.fileToRun, '/package.json']
   const loaded = await addPreLoadAll(sw, preLoad, true)
-  console.log(Date.now() - time, 'preload', loaded)
 
   sw.projectName = sw.defProjectName
   if (sw.fileToRun !== 'index.js') sw.projectName = sw.fileToRun.replace(/\.js$/, '')
diff --git a/packages/require/src/require.js b/packages/require/src/require.js
index 8a41eca..89aa168 100644
--- a/packages/require/src/require.js
+++ b/packages/require/src/require.js
@@ -10,6 +10,7 @@
 - typescript import must use .js (it is a bit strange, but probably has good reasons)
 */
 
+import { extractPathInfo } from '../../fs-provider/fs-provider'
 import { MODULE_BASE, getExtension, resolveUrl } from './resolveUrl'
 
 export { resolveUrl } from './resolveUrl'
@@ -49,7 +50,9 @@ export const require = (urlOrSource, transform, readFile, base, root, importData
     const resolvedStr = resolved.url.toString()
     const isJs = resolvedStr.endsWith('.ts') || resolvedStr.endsWith('.js')
     if(!isJs && importData){
-      return importData(resolvedStr, readFile, base, root, moduleBase)
+      const info = extractPathInfo(resolvedStr)
+      let content = readFile(resolvedStr,{output: importData.isBinaryExt(info.ext)})
+      return importData.deserialize(info, content)
     }
 
     isRelativeFile = resolved.isRelativeFile
diff --git a/packages/worker/worker.js b/packages/worker/worker.js
index 7ab9650..98338ca 100644
--- a/packages/worker/worker.js
+++ b/packages/worker/worker.js
@@ -5,6 +5,7 @@ import { clearFileCache, clearTempCache, readFileWeb, require, requireCache, res
 import { exportStlText } from './src/exportStlText.js'
 import { combineParameterDefinitions, getParameterDefinitionsFromSource } from './src/getParameterDefinitionsFromSource.js'
 import { extractDefaults } from './src/extractDefaults.js'
+import { extractPathInfo, readAsArrayBuffer, readAsText } from '../fs-provider/fs-provider.js'
 
 let main
 self.JSCAD_WORKER_ENV = {}
@@ -41,8 +42,22 @@ export const init = params => {
   userInstances = params.userInstances
 }
 
+async function readFileFile(file, {bin=false}={}){
+  if(bin) return await readAsArrayBuffer(file)
+  else return readAsText(file)
+}
+
 solids = []
 export async function runMain({ params } = {}) {
+  params = {...params}
+  for(let p in params){
+    if(params[p] instanceof File && importData){
+      const info = extractPathInfo(params[p].name)
+      let content = await readFileFile(params[p],{bin: importData.isBinaryExt(info.ext)})
+      params[p] = importData.deserialize(info, content)
+    }
+  }
+  console.log('runMain', params)
   let entities = []
   const transferable = []