diff --git a/frontend/src/App.vue b/frontend/src/App.vue
index d7a91d5..a862b9a 100644
--- a/frontend/src/App.vue
+++ b/frontend/src/App.vue
@@ -1,13 +1,13 @@
 <template>
   <LoginModal />
   <header>
-    <HeaderMain ref="headerMain" :path="path.pathList">
+    <HeaderMain ref="headerMain" :path="path.pathList" :query="path.query">
       <HeaderSelected :path="path.pathList" />
     </HeaderMain>
     <BreadCrumb :path="path.pathList" tabindex="-1"/>
   </header>
   <main>
-    <RouterView :path="path.pathList" />
+    <RouterView :path="path.pathList" :query="path.query" />
   </main>
 </template>
 
@@ -16,7 +16,7 @@ import { RouterView } from 'vue-router'
 import type { ComputedRef } from 'vue'
 import type HeaderMain from '@/components/HeaderMain.vue'
 import { onMounted, onUnmounted, ref, watchEffect } from 'vue'
-import { watchConnect, watchDisconnect } from '@/repositories/WS'
+import { loadSession, watchConnect, watchDisconnect } from '@/repositories/WS'
 import { useDocumentStore } from '@/stores/documents'
 
 import { computed } from 'vue'
@@ -25,19 +25,23 @@ import Router from '@/router/index'
 interface Path {
   path: string
   pathList: string[]
+  query: string
 }
 const documentStore = useDocumentStore()
 const path: ComputedRef<Path> = computed(() => {
-  const p = decodeURIComponent(Router.currentRoute.value.path)
-  const pathList = p.split('/').filter(value => value !== '')
+  const p = decodeURIComponent(Router.currentRoute.value.path).split('//')
+  const pathList = p[0].split('/').filter(value => value !== '')
+  const query = p.slice(1).join('//')
   return {
-    path: p,
-    pathList
+    path: p[0],
+    pathList,
+    query
   }
 })
 watchEffect(() => {
   document.title = path.value.path.replace(/\/$/, '').split('/').pop() || documentStore.server.name || 'Cista Storage'
 })
+onMounted(loadSession)
 onMounted(watchConnect)
 onUnmounted(watchDisconnect)
 // Update human-readable x seconds ago messages from mtimes
diff --git a/frontend/src/repositories/Document.ts b/frontend/src/repositories/Document.ts
index 57355b4..022b260 100644
--- a/frontend/src/repositories/Document.ts
+++ b/frontend/src/repositories/Document.ts
@@ -22,29 +22,16 @@ export type errorEvent = {
 
 // Raw types the backend /api/watch sends us
 
-export type FileEntry = {
-  key: FUID
-  size: number
-  mtime: number
-}
+export type FileEntry = [
+  number,  // level
+  string,  // name
+  FUID,
+  number, //mtime
+  number, // size
+  number, // isfile
+]
 
-export type DirEntry = {
-  key: FUID
-  size: number
-  mtime: number
-  dir: DirList
-}
-
-export type DirList = Record<string, FileEntry | DirEntry>
-
-export type UpdateEntry = {
-  name: string
-  deleted?: boolean
-  key?: FUID
-  size?: number
-  mtime?: number
-  dir?: DirList
-}
+export type UpdateEntry = ['k', number] | ['d', number] | ['i', Array<FileEntry>]
 
 // Helper structure for selections
 export interface SelectedItems {
diff --git a/frontend/src/repositories/WS.ts b/frontend/src/repositories/WS.ts
index d5ebf8a..0570921 100644
--- a/frontend/src/repositories/WS.ts
+++ b/frontend/src/repositories/WS.ts
@@ -1,14 +1,29 @@
 import { useDocumentStore } from "@/stores/documents"
-import type { DirEntry, UpdateEntry, errorEvent } from "./Document"
+import type { FileEntry, UpdateEntry, errorEvent } from "./Document"
 
 export const controlUrl = '/api/control'
 export const uploadUrl = '/api/upload'
 export const watchUrl = '/api/watch'
 
-let tree = null as DirEntry | null
+let tree = [] as FileEntry[]
 let reconnectDuration = 500
 let wsWatch = null as WebSocket | null
 
+export const loadSession = () => {
+  const store = useDocumentStore()
+  try {
+    tree = JSON.parse(sessionStorage["cista-files"])
+    store.updateRoot(tree)
+    return true
+  } catch (error) {
+    return false
+  }
+}
+
+const saveSession = () => {
+  sessionStorage["cista-files"] = JSON.stringify(tree)
+}
+
 export const connect = (path: string, handlers: Partial<Record<keyof WebSocketEventMap, any>>) => {
   const webSocket = new WebSocket(new URL(path, location.origin.replace(/^http/, 'ws')))
   for (const [event, handler] of Object.entries(handlers)) webSocket.addEventListener(event, handler)
@@ -99,29 +114,31 @@ function handleRootMessage({ root }: { root: DirEntry }) {
   console.log('Watch root', root)
   store.updateRoot(root)
   tree = root
+  saveSession()
 }
 
 function handleUpdateMessage(updateData: { update: UpdateEntry[] }) {
   const store = useDocumentStore()
-  console.log('Watch update', updateData.update)
+  const update = updateData.update
+  console.log('Watch update', update)
   if (!tree) return console.error('Watch update before root')
-  let node: DirEntry = tree
-  for (const elem of updateData.update) {
-    if (elem.deleted) {
-      delete node.dir[elem.name]
-      break // Deleted elements can't have further children
-    }
-    if (elem.name) {
-      // @ts-ignore
-      console.log(node, elem.name)
-      node = node.dir[elem.name] ||= {}
-    }
-    if (elem.key !== undefined) node.key = elem.key
-    if (elem.size !== undefined) node.size = elem.size
-    if (elem.mtime !== undefined) node.mtime = elem.mtime
-    if (elem.dir !== undefined) node.dir = elem.dir
+  let newtree = []
+  let oidx = 0
+
+  for (const [action, arg] of update) {
+      if (action === 'k') {
+          newtree.push(...tree.slice(oidx, oidx + arg))
+          oidx += arg
+      }
+      else if (action === 'd') oidx += arg
+      else if (action === 'i') newtree.push(...arg)
+      else console.log("Unknown update action", action, arg)
   }
-  store.updateRoot(tree)
+  if (oidx != tree.length)
+    throw Error(`Tree update out of sync, number of entries mismatch: got ${oidx}, expected ${tree.length}`)
+  store.updateRoot(newtree)
+  tree = newtree
+  saveSession()
 }
 
 function handleError(msg: errorEvent) {
diff --git a/frontend/src/stores/documents.ts b/frontend/src/stores/documents.ts
index 97c6ca6..985d5fd 100644
--- a/frontend/src/stores/documents.ts
+++ b/frontend/src/stores/documents.ts
@@ -1,10 +1,4 @@
-import type {
-  Document,
-  DirEntry,
-  FileEntry,
-  FUID,
-  SelectedItems
-} from '@/repositories/Document'
+import type { Document, FileEntry, FUID, SelectedItems } from '@/repositories/Document'
 import { formatSize, formatUnixDate, haystackFormat } from '@/utils'
 import { defineStore } from 'pinia'
 import { collator } from '@/utils'
@@ -26,7 +20,6 @@ export const useDocumentStore = defineStore({
   id: 'documents',
   state: () => ({
     document: [] as Document[],
-    search: "" as string,
     selected: new Set<FUID>(),
     uploadingDocuments: [],
     uploadCount: 0 as number,
@@ -41,46 +34,27 @@ export const useDocumentStore = defineStore({
       isOpenLoginModal: false
     } as User
   }),
-  persist: {
-    storage: sessionStorage,
-    paths: ['document'],
-  },
   actions: {
-    updateRoot(root: DirEntry | null = null) {
-      if (!root) {
-        this.document = []
-        return
-      }
-      // Transform tree data to flat documents array
-      let loc = ""
-      const mapper = ([name, attr]: [string, FileEntry | DirEntry]) => ({
-        ...attr,
-        loc,
-        name,
-        sizedisp: formatSize(attr.size),
-        modified: formatUnixDate(attr.mtime),
-        haystack: haystackFormat(name),
-      })
-      const queue = [...Object.entries(root.dir ?? {}).map(mapper)]
+    updateRoot(root: FileEntry[]) {
       const docs = []
-      for (let doc; (doc = queue.shift()) !== undefined;) {
-        docs.push(doc)
-        if ("dir" in doc) {
-          // Recurse but replace recursive structure with boolean
-          loc = doc.loc ? `${doc.loc}/${doc.name}` : doc.name
-          queue.push(...Object.entries(doc.dir).map(mapper))
-          // @ts-ignore
-          doc.dir = true
-        }
-        // @ts-ignore
-        else doc.dir = false
+      let loc = [] as string[]
+      for (const [level, name, key, mtime, size, isfile] of root) {
+        if (level === 0) continue
+        loc = loc.slice(0, level - 1)
+        docs.push({
+          name,
+          loc: loc.join('/'),
+          key,
+          size,
+          sizedisp: formatSize(size),
+          mtime,
+          modified: formatUnixDate(mtime),
+          haystack: haystackFormat(name),
+          dir: !isfile,
+        })
+        loc.push(name)
       }
-      // Pre sort directory entries folders first then files, names in natural ordering
-      docs.sort((a, b) =>
-        // @ts-ignore
-        b.dir - a.dir ||
-        collator.compare(a.name, b.name)
-      )
+      console.log("Documents", docs)
       this.document = docs as Document[]
     },
     login(username: string, privileged: boolean) {
diff --git a/frontend/src/views/ExplorerView.vue b/frontend/src/views/ExplorerView.vue
index b163caa..773d2ee 100644
--- a/frontend/src/views/ExplorerView.vue
+++ b/frontend/src/views/ExplorerView.vue
@@ -16,17 +16,17 @@ import { needleFormat, localeIncludes, collator } from '@/utils';
 
 const documentStore = useDocumentStore()
 const fileExplorer = ref()
-const props = defineProps({
+const props = defineProps<{
   path: Array<string>
-})
+  query: string
+}>()
 const documents = computed(() => {
-  if (!props.path) return []
   const loc = props.path.join('/')
+  const query = props.query
   // List the current location
-  if (!documentStore.search) return documentStore.document.filter(doc => doc.loc === loc)
+  if (!query) return documentStore.document.filter(doc => doc.loc === loc)
   // Find up to 100 newest documents that match the search
-  const search = documentStore.search
-  const needle = needleFormat(search)
+  const needle = needleFormat(query)
   let limit = 100
   let docs = []
   for (const doc of documentStore.recentDocuments) {
@@ -46,7 +46,7 @@ const documents = computed(() => {
     // @ts-ignore
     (a.type === 'file') - (b.type === 'file') ||
     // @ts-ignore
-    b.name.includes(search) - a.name.includes(search) ||
+    b.name.includes(query) - a.name.includes(query) ||
     collator.compare(a.name, b.name)
   ))
   return docs