diff --git a/frontend/controller/namespace.js b/frontend/controller/namespace.js
index 3d147b5670..33417a9fa5 100644
--- a/frontend/controller/namespace.js
+++ b/frontend/controller/namespace.js
@@ -1,17 +1,16 @@
 'use strict'
 
 import sbp from '@sbp/sbp'
-import Vue from 'vue'
 
 // NOTE: prefix groups with `group/` and users with `user/` ?
 sbp('sbp/selectors/register', {
   'namespace/lookupCached': (name: string) => {
     const cache = sbp('state/vuex/state').namespaceLookups
-    return cache[name] ?? null
+    return cache?.[name] ?? null
   },
   'namespace/lookupReverseCached': (id: string) => {
     const cache = sbp('state/vuex/state').reverseNamespaceLookups
-    return cache[id] ?? null
+    return cache?.[id] ?? null
   },
   'namespace/lookup': (name: string, { skipCache }: { skipCache: boolean } = { skipCache: false }) => {
     if (!skipCache) {
@@ -23,23 +22,6 @@ sbp('sbp/selectors/register', {
         return Promise.resolve(cached)
       }
     }
-    return fetch(`${sbp('okTurtles.data/get', 'API_URL')}/name/${encodeURIComponent(name)}`).then((r: Object) => {
-      if (!r.ok) {
-        console.warn(`namespace/lookup: ${r.status} for ${name}`)
-        if (r.status !== 404) {
-          throw new Error(`${r.status}: ${r.statusText}`)
-        }
-        return null
-      }
-      return r['text']()
-    }).then(value => {
-      if (value !== null) {
-        const cache = sbp('state/vuex/state').namespaceLookups
-        const reverseCache = sbp('state/vuex/state').reverseNamespaceLookups
-        Vue.set(cache, name, value)
-        Vue.set(reverseCache, value, name)
-      }
-      return value
-    })
+    return sbp('sw-namespace/lookup', name, { skipCache })
   }
 })
diff --git a/frontend/controller/service-worker.js b/frontend/controller/service-worker.js
index 2259341d16..79f5e24b2d 100644
--- a/frontend/controller/service-worker.js
+++ b/frontend/controller/service-worker.js
@@ -1,10 +1,11 @@
 'use strict'
 
-import sbp from '@sbp/sbp'
 import { PUBSUB_INSTANCE } from '@controller/instance-keys.js'
-import { REQUEST_TYPE, PUSH_SERVER_ACTION_TYPE, PUBSUB_RECONNECTION_SUCCEEDED, createMessage } from '~/shared/pubsub.js'
-import { HOURS_MILLIS } from '~/frontend/model/contracts/shared/time.js'
+import sbp from '@sbp/sbp'
 import { PWA_INSTALLABLE } from '@utils/events.js'
+import { HOURS_MILLIS } from '~/frontend/model/contracts/shared/time.js'
+import { PUBSUB_RECONNECTION_SUCCEEDED, PUSH_SERVER_ACTION_TYPE, REQUEST_TYPE, createMessage } from '~/shared/pubsub.js'
+import { deserializer } from '~/shared/serdes/index.js'
 
 const pwa = {
   deferredInstallPrompt: null,
@@ -66,6 +67,11 @@ sbp('sbp/selectors/register', {
               sbp('service-worker/resubscribe-push', data.subscription)
               break
             }
+            case 'event': {
+              console.error('@@@EVENT RECEIVED', event.data.subtype, ...deserializer(event.data.data))
+              sbp('okTurtles.events/emit', event.data.subtype, ...deserializer(event.data.data))
+              break
+            }
             default:
               console.error('[sw] Received unknown message type from the service worker:', data)
               break
diff --git a/frontend/controller/serviceworkers/sw-primary.js b/frontend/controller/serviceworkers/sw-primary.js
index c68a1de449..2dacb4065d 100644
--- a/frontend/controller/serviceworkers/sw-primary.js
+++ b/frontend/controller/serviceworkers/sw-primary.js
@@ -1,5 +1,23 @@
 'use strict'
 
+import { PROPOSAL_ARCHIVED } from '@model/contracts/shared/constants.js'
+import '@sbp/okturtles.data'
+import '@sbp/okturtles.eventqueue'
+import '@sbp/okturtles.events'
+import sbp from '@sbp/sbp'
+import '~/frontend/controller/actions/index.js'
+import setupChelonia from '~/frontend/setupChelonia.js'
+import { LOGIN, LOGIN_ERROR, LOGOUT } from '~/frontend/utils/events.js'
+import { GIMessage } from '~/shared/domains/chelonia/GIMessage.js'
+import { Secret } from '~/shared/domains/chelonia/Secret.js'
+import { CONTRACTS_MODIFIED, CONTRACT_IS_SYNCING, EVENT_HANDLED } from '~/shared/domains/chelonia/events.js'
+import { deserializer, serializer } from '~/shared/serdes/index.js'
+import { ACCEPTED_GROUP, DELETED_CHATROOM, JOINED_CHATROOM, JOINED_GROUP, LEFT_CHATROOM, LEFT_GROUP, NAMESPACE_REGISTRATION, SWITCH_GROUP } from '../../utils/events.js'
+import '~/frontend/controller/sw-namespace.js'
+
+deserializer.register(GIMessage)
+deserializer.register(Secret)
+
 // https://serviceworke.rs/message-relay_service-worker_doc.html
 // https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API/Using_Service_Workers
 // https://jakearchibald.com/2014/using-serviceworker-today/
@@ -7,6 +25,44 @@
 // https://frontendian.co/service-workers
 // https://stackoverflow.com/a/49748437 => https://medium.com/@nekrtemplar/self-destroying-serviceworker-73d62921d717 => https://love2dev.com/blog/how-to-uninstall-a-service-worker/
 
+sbp('sbp/filters/global/add', (domain, selector, data) => {
+  // if (domainBlacklist[domain] || selectorBlacklist[selector]) return
+  console.debug(`[sw] [sbp] ${selector}`, data)
+});
+
+[EVENT_HANDLED, CONTRACTS_MODIFIED, CONTRACT_IS_SYNCING, LOGIN, LOGIN_ERROR, LOGOUT, ACCEPTED_GROUP, DELETED_CHATROOM, LEFT_CHATROOM, LEFT_GROUP, JOINED_CHATROOM, JOINED_GROUP, NAMESPACE_REGISTRATION, SWITCH_GROUP, PROPOSAL_ARCHIVED].forEach(et => {
+  sbp('okTurtles.events/on', et, (...args) => {
+    const { data } = serializer(args)
+    const message = {
+      type: 'event',
+      subtype: et,
+      data
+    }
+    self.clients.matchAll()
+      .then((clientList) => {
+        clientList.forEach((client) => {
+          client.postMessage(message)
+        })
+      })
+  })
+})
+
+sbp('sbp/selectors/register', {
+  'state/vuex/state': () => {
+    // TODO: Remove this selector once it's removed from contracts
+    return sbp('chelonia/rootState')
+  },
+  'state/vuex/reset': () => {
+    console.error('[sw] CALLED state/vuex/reset WHICH IS UNDEFINED')
+  },
+  'state/vuex/save': () => {
+    console.error('[sw] CALLED state/vuex/save WHICH IS UNDEFINED')
+  },
+  'state/vuex/commit': () => {
+    console.error('[sw] CALLED state/vuex/commit WHICH IS UNDEFINED')
+  }
+})
+
 self.addEventListener('install', function (event) {
   console.debug('[sw] install')
   event.waitUntil(self.skipWaiting())
@@ -16,7 +72,7 @@ self.addEventListener('activate', function (event) {
   console.debug('[sw] activate')
 
   // 'clients.claim()' reference: https://web.dev/articles/service-worker-lifecycle#clientsclaim
-  event.waitUntil(self.clients.claim())
+  event.waitUntil(setupChelonia().then(() => self.clients.claim()))
 })
 
 self.addEventListener('fetch', function (event) {
@@ -57,6 +113,17 @@ self.addEventListener('message', function (event) {
       case 'store-client-id':
         store.clientId = event.source.id
         break
+      case 'sbp': {
+        const port = event.data.port;
+        (async () => await sbp(...deserializer(event.data.data)))().then((r) => {
+          const { data, transferables } = serializer(r)
+          port.postMessage([true, data], transferables)
+        }).catch((e) => {
+          const { data, transferables } = serializer(e)
+          port.postMessage([false, data], transferables)
+        })
+        break
+      }
       case 'ping':
         event.source.postMessage({ type: 'pong' })
         break
diff --git a/frontend/controller/sw-namespace.js b/frontend/controller/sw-namespace.js
new file mode 100644
index 0000000000..00b63ac803
--- /dev/null
+++ b/frontend/controller/sw-namespace.js
@@ -0,0 +1,51 @@
+'use strict'
+
+import sbp from '@sbp/sbp'
+import { NAMESPACE_REGISTRATION } from '../utils/events.js'
+
+// NOTE: prefix groups with `group/` and users with `user/` ?
+sbp('sbp/selectors/register', {
+  'namespace/lookupCached': (name: string) => {
+    const cache = sbp('chelonia/rootState').namespaceLookups
+    // 'cache' may be undefined when starting up or after calling chelonia/reset
+    return cache?.[name] ?? null
+  },
+  'namespace/lookupReverseCached': (id: string) => {
+    const cache = sbp('chelonia/rootState').reverseNamespaceLookups
+    return cache?.[id] ?? null
+  },
+  'namespace/lookup': (name: string, { skipCache }: { skipCache: boolean } = { skipCache: false }) => {
+    if (!skipCache) {
+      const cached = sbp('namespace/lookupCached', name)
+      if (cached) {
+        // Wrapping in a Promise to return a consistent type across all execution
+        // paths (next return is a Promise)
+        // This way we can call .then() on the result
+        return Promise.resolve(cached)
+      }
+    }
+    return fetch(`${sbp('okTurtles.data/get', 'API_URL')}/name/${encodeURIComponent(name)}`).then((r: Object) => {
+      if (!r.ok) {
+        console.warn(`namespace/lookup: ${r.status} for ${name}`)
+        if (r.status !== 404) {
+          throw new Error(`${r.status}: ${r.statusText}`)
+        }
+        return null
+      }
+      return r['text']()
+    }).then(value => {
+      if (value !== null) {
+        const reactiveSet = sbp('chelonia/config').reactiveSet
+        const rootState = sbp('chelonia/rootState')
+        if (!rootState.namespaceLookups) reactiveSet(rootState, 'namespaceLookups', Object.create(null))
+        if (!rootState.reverseNamespaceLookups) reactiveSet(rootState, 'reverseNamespaceLookups', Object.create(null))
+        const cache = rootState.namespaceLookups
+        const reverseCache = rootState.reverseNamespaceLookups
+        reactiveSet(cache, name, value)
+        reactiveSet(reverseCache, value, name)
+        sbp('okTurtles.events/emit', NAMESPACE_REGISTRATION, { name, value })
+      }
+      return value
+    })
+  }
+})
diff --git a/frontend/main.js b/frontend/main.js
index b54c7b28d3..e8affabb9f 100644
--- a/frontend/main.js
+++ b/frontend/main.js
@@ -11,12 +11,10 @@ import ALLOWED_URLS from '@view-utils/allowedUrls.js'
 import IdleVue from 'idle-vue'
 import { mapGetters, mapMutations, mapState } from 'vuex'
 import 'wicg-inert'
-import '~/shared/domains/chelonia/chelonia.js'
 import { CONTRACT_IS_SYNCING } from '~/shared/domains/chelonia/events.js'
 import '~/shared/domains/chelonia/localSelectors.js'
 import { KV_KEYS } from './utils/constants.js'
 // import '~/shared/domains/chelonia/persistent-actions.js' // Commented out as persistentActions are not being used
-import './controller/actions/index.js'
 import './controller/app/index.js'
 import './controller/backend.js'
 import './controller/namespace.js'
@@ -24,7 +22,7 @@ import router from './controller/router.js'
 import './controller/service-worker.js'
 import { SETTING_CURRENT_USER } from './model/database.js'
 import store from './model/state.js'
-import { KV_EVENT, LOGIN_COMPLETE, LOGIN_ERROR, LOGOUT, OFFLINE, ONLINE, RECONNECTING, RECONNECTION_FAILED, SWITCH_GROUP, THEME_CHANGE } from './utils/events.js'
+import { KV_EVENT, LOGIN_COMPLETE, LOGIN_ERROR, LOGOUT, NAMESPACE_REGISTRATION, OFFLINE, ONLINE, RECONNECTING, RECONNECTION_FAILED, SWITCH_GROUP, THEME_CHANGE } from './utils/events.js'
 import AppStyles from './views/components/AppStyles.vue'
 import BannerGeneral from './views/components/banners/BannerGeneral.vue'
 import Modal from './views/components/modal/Modal.vue'
@@ -35,14 +33,19 @@ import './views/utils/ui.js'
 import './views/utils/vError.js'
 import './views/utils/vFocus.js'
 // import './views/utils/vSafeHtml.js' // this gets imported by translations, which is part of common.js
+import { GIMessage } from '~/shared/domains/chelonia/GIMessage.js'
+import { Secret } from '~/shared/domains/chelonia/Secret.js'
+import { deserializer, serializer } from '~/shared/serdes/index.js'
 import notificationsMixin from './model/notifications/mainNotificationsMixin.js'
 import './model/notifications/periodicNotifications.js'
-import setupChelonia from './setupChelonia.js'
 import FaviconBadge from './utils/faviconBadge.js'
 import './utils/touchInteractions.js'
 import { showNavMixin } from './views/utils/misc.js'
 import './views/utils/vStyle.js'
 
+deserializer.register(GIMessage)
+deserializer.register(Secret)
+
 const { Vue, L, LError } = Common
 
 console.info('GI_VERSION:', process.env.GI_VERSION)
@@ -99,10 +102,12 @@ async function startApp () {
   // TODO: [SW] The following will be needed to keep namespace registrations
   // in sync between the SW and each tab. It is not needed now because everything
   // is running in the same context
-  /* sbp('okTurtles.events/on', NAMESPACE_REGISTRATION, ({ name, value }) => {
+  sbp('okTurtles.events/on', NAMESPACE_REGISTRATION, ({ name, value }) => {
     const cache = sbp('state/vuex/state').namespaceLookups
+    const reverseCache = sbp('state/vuex/state').reverseNamespaceLookups
     Vue.set(cache, name, value)
-  }) */
+    Vue.set(reverseCache, value, name)
+  })
 
   // NOTE: setting 'EXPOSE_SBP' in production will make it easier for users to generate contract
   //       actions that they shouldn't be generating, which can lead to bugs or trigger the automated
@@ -154,6 +159,55 @@ async function startApp () {
     throw e
   })
 
+  /* TODO: MOVE TO ANOTHER FILE */
+  sbp('okTurtles.data/set', 'API_URL', self.location.origin)
+  const swRpc = (() => {
+    let controller = navigator.serviceWorker.controller
+    navigator.serviceWorker.addEventListener('controllerchange', (ev) => {
+      controller = navigator.serviceWorker.controller
+    }, false)
+
+    return (...args) => {
+      return new Promise((resolve, reject) => {
+        const messageChannel = new MessageChannel()
+        messageChannel.port1.addEventListener('message', (event) => {
+          if (event.data && Array.isArray(event.data)) {
+            const r = deserializer(event.data[1])
+            if (event.data[0] === true) {
+              resolve(r)
+            } else {
+              reject(r)
+            }
+            messageChannel.port1.close()
+          }
+        }, false)
+        messageChannel.port1.addEventListener('messageerror', (event) => {
+          reject(event.data)
+          messageChannel.port1.close()
+        }, false)
+        messageChannel.port1.start()
+        const { data, transferables } = serializer(args)
+        controller.postMessage({
+          type: 'sbp',
+          port: messageChannel.port2,
+          data
+        }, [messageChannel.port2, ...transferables])
+      })
+    }
+  })()
+
+  sbp('sbp/selectors/register', {
+    'gi.actions/*': swRpc
+  })
+  sbp('sbp/selectors/register', {
+    'chelonia/*': swRpc
+  })
+  sbp('sbp/selectors/register', {
+    'sw-namespace/*': (...args) => {
+      return swRpc(args[0].slice(3), ...args.slice(1))
+    }
+  })
+
   /* eslint-disable no-new */
   new Vue({
     router: router,
@@ -298,7 +352,7 @@ async function startApp () {
       // happened (an example where things can happen this quickly is in the
       // tests).
       let oldIdentityContractID = null
-      setupChelonia().then(() => sbp('gi.db/settings/load', SETTING_CURRENT_USER)).then(async (identityContractID) => {
+      Promise.resolve().then(() => sbp('gi.db/settings/load', SETTING_CURRENT_USER)).then(async (identityContractID) => {
         oldIdentityContractID = identityContractID
         if (!identityContractID || this.ephemeral.finishedLogin === 'yes') return
         await sbp('gi.app/identity/login', { identityContractID })
diff --git a/frontend/setupChelonia.js b/frontend/setupChelonia.js
index 6a74ff0557..1285b3d8bb 100644
--- a/frontend/setupChelonia.js
+++ b/frontend/setupChelonia.js
@@ -58,7 +58,7 @@ const setupChelonia = async (): Promise<*> => {
   })
 
   // this is to ensure compatibility between frontend and test/backend.test.js
-  sbp('okTurtles.data/set', 'API_URL', window.location.origin)
+  sbp('okTurtles.data/set', 'API_URL', self.location.origin)
 
   // Used in 'chelonia/configure' hooks to emit an error notification.
   const errorNotification = (activity: string, error: Error, message: GIMessage) => {
@@ -131,13 +131,14 @@ const setupChelonia = async (): Promise<*> => {
         exposedGlobals: {
           // note: needs to be written this way and not simply "Notification"
           // because that breaks on mobile where Notification is undefined
-          Notification: window.Notification
+          Notification: self.Notification
         }
       }
     },
     hooks: {
       handleEventError: (e: Error, message: GIMessage) => {
         if (e.name === 'ChelErrorUnrecoverable') {
+          // TODO: Forward to app
           sbp('gi.ui/seriousErrorBanner', e)
         }
         if (sbp('okTurtles.data/get', 'sideEffectError') !== message.hash()) {
diff --git a/shared/domains/chelonia/GIMessage.js b/shared/domains/chelonia/GIMessage.js
index e6c7460862..e772b2bd9d 100644
--- a/shared/domains/chelonia/GIMessage.js
+++ b/shared/domains/chelonia/GIMessage.js
@@ -474,7 +474,7 @@ export class GIMessage {
 
   // $FlowFixMe[unsupported-syntax]
   static [serdesSerializeSymbol] (m: GIMessage) {
-    return [m.serialize(), m.direction(), m.decryptedValue(), m.innerSigningKey()]
+    return [m.serialize(), m.direction(), m.decryptedValue(), m.innerSigningKeyId()]
   }
 
   // $FlowFixMe[unsupported-syntax]
diff --git a/shared/domains/chelonia/crypto.js b/shared/domains/chelonia/crypto.js
index 9acb60cf2c..0ff0fb4a4b 100644
--- a/shared/domains/chelonia/crypto.js
+++ b/shared/domains/chelonia/crypto.js
@@ -21,6 +21,7 @@ export const EXTERNALKM32 = 'externalkm32'
 
 const bytesOrObjectToB64 = (ary: Uint8Array) => {
   if (!(ary instanceof Uint8Array)) {
+    console.error('@@@bytesOrObjectToB64', ary, ary.constructor, ary instanceof Uint8Array)
     throw Error('Unsupported type')
   }
   return bytesToB64(ary)
diff --git a/shared/serdes/index.js b/shared/serdes/index.js
index 64449872f2..99d27d0077 100644
--- a/shared/serdes/index.js
+++ b/shared/serdes/index.js
@@ -58,19 +58,25 @@ export const serializer = (data: any): any => {
       return rawResult(['_', 'Set', Array.from(value.entries())])
     }
     // Error, Blob, File, etc. are supported by structuredClone but not by JSON
-    // We mark these as 'refs', so that the reviver can undo tris transformation
+    // We mark these as 'refs', so that the reviver can undo this transformation
     if (value instanceof Error || value instanceof Blob || value instanceof File) {
       const pos = verbatim.length
       verbatim[verbatim.length] = value
       return rawResult(['_', '_ref', pos])
     }
     // Same for other types supported by structuredClone but not JSON
-    if (value instanceof MessagePort || value instanceof ReadableStream || value instanceof WritableStream || ArrayBuffer.isView(value) || value instanceof ArrayBuffer) {
+    if (value instanceof MessagePort || value instanceof ReadableStream || value instanceof WritableStream || value instanceof ArrayBuffer) {
       const pos = verbatim.length
       verbatim[verbatim.length] = value
       transferables.add(value)
       return rawResult(['_', '_ref', pos])
     }
+    if (ArrayBuffer.isView(value)) {
+      const pos = verbatim.length
+      verbatim[verbatim.length] = value
+      transferables.add(value.buffer)
+      return rawResult(['_', '_ref', pos])
+    }
     // Functions aren't supported neither by structuredClone nor JSON. However,
     // we can convert functions into a MessagePort, which is supported
     if (typeof value === 'function') {