diff --git a/models/calendar/package.json b/models/calendar/package.json
index efeb97a6df..54b324efe5 100644
--- a/models/calendar/package.json
+++ b/models/calendar/package.json
@@ -34,7 +34,6 @@
     "@hcengineering/view": "^0.6.9",
     "@hcengineering/model-attachment": "^0.6.0",
     "@hcengineering/setting": "^0.6.11",
-    "@hcengineering/model-task": "^0.6.0",
     "@hcengineering/calendar": "^0.6.17",
     "@hcengineering/calendar-resources": "^0.6.0",
     "@hcengineering/platform": "^0.6.9",
diff --git a/models/calendar/src/index.ts b/models/calendar/src/index.ts
index d0c620a02d..ea8735dcbd 100644
--- a/models/calendar/src/index.ts
+++ b/models/calendar/src/index.ts
@@ -25,10 +25,17 @@ import {
   type Visibility
 } from '@hcengineering/calendar'
 import { type Contact } from '@hcengineering/contact'
-import { DateRangeMode, type Domain, IndexKind, type Markup, type Ref, type Timestamp } from '@hcengineering/core'
+import {
+  DateRangeMode,
+  IndexKind,
+  type SystemSpace,
+  type Domain,
+  type Markup,
+  type Ref,
+  type Timestamp
+} from '@hcengineering/core'
 import {
   ArrOf,
-  type Builder,
   Collection,
   Index,
   Mixin,
@@ -41,12 +48,12 @@ import {
   TypeRef,
   TypeString,
   TypeTimestamp,
-  UX
+  UX,
+  type Builder
 } from '@hcengineering/model'
 import attachment from '@hcengineering/model-attachment'
 import contact from '@hcengineering/model-contact'
-import core, { TAttachedDoc, TClass } from '@hcengineering/model-core'
-import { TProject } from '@hcengineering/model-task'
+import core, { TAttachedDoc, TClass, TDoc } from '@hcengineering/model-core'
 import view, { createAction } from '@hcengineering/model-view'
 import notification from '@hcengineering/notification'
 import setting from '@hcengineering/setting'
@@ -59,9 +66,11 @@ export { calendarOperation } from './migration'
 
 export const DOMAIN_CALENDAR = 'calendar' as Domain
 
-@Model(calendar.class.Calendar, core.class.Space)
+@Model(calendar.class.Calendar, core.class.Doc, DOMAIN_CALENDAR)
 @UX(calendar.string.Calendar, calendar.icon.Calendar)
-export class TCalendar extends TProject implements Calendar {
+export class TCalendar extends TDoc implements Calendar {
+  name!: string
+  hidden!: boolean
   visibility!: Visibility
 }
 
@@ -76,7 +85,10 @@ export class TExternalCalendar extends TCalendar implements ExternalCalendar {
 @Model(calendar.class.Event, core.class.AttachedDoc, DOMAIN_CALENDAR)
 @UX(calendar.string.Event, calendar.icon.Calendar)
 export class TEvent extends TAttachedDoc implements Event {
-  declare space: Ref<Calendar>
+  declare space: Ref<SystemSpace>
+
+  @Prop(TypeRef(calendar.class.Calendar), calendar.string.Calendar)
+    calendar!: Ref<Calendar>
 
   eventId!: string
 
diff --git a/models/calendar/src/migration.ts b/models/calendar/src/migration.ts
index eca6bb9862..e00cde0a33 100644
--- a/models/calendar/src/migration.ts
+++ b/models/calendar/src/migration.ts
@@ -13,10 +13,10 @@
 // limitations under the License.
 //
 
-import { calendarId, type Calendar, type Event, type ReccuringEvent } from '@hcengineering/calendar'
-import contact from '@hcengineering/contact'
-import core, { TxOperations, type Ref } from '@hcengineering/core'
+import { calendarId, type Event, type ReccuringEvent } from '@hcengineering/calendar'
+import { type Ref, type Space } from '@hcengineering/core'
 import {
+  createDefaultSpace,
   tryMigrate,
   tryUpgrade,
   type MigrateOperation,
@@ -24,68 +24,47 @@ import {
   type MigrationUpgradeClient
 } from '@hcengineering/model'
 import { DOMAIN_SPACE } from '@hcengineering/model-core'
-import { DOMAIN_SETTING } from '@hcengineering/model-setting'
-import { type Integration } from '@hcengineering/setting'
 import { DOMAIN_CALENDAR } from '.'
 import calendar from './plugin'
 
-async function migrateCalendars (tx: TxOperations): Promise<void> {
-  const existCalendars = new Set((await tx.findAll(calendar.class.Calendar, {})).map((p) => p._id))
-  const users = await tx.findAll(contact.class.PersonAccount, {})
-  for (const user of users) {
-    if (!existCalendars.has(`${user._id}_calendar` as Ref<Calendar>)) {
-      await tx.createDoc(
-        calendar.class.Calendar,
-        core.space.Space,
-        {
-          name: user.email,
-          description: '',
-          archived: false,
-          private: false,
-          members: [user._id],
-          visibility: 'public'
-        },
-        `${user._id}_calendar` as Ref<Calendar>,
-        undefined,
-        user._id
-      )
-    }
-  }
-  const events = await tx.findAll(calendar.class.Event, { space: calendar.space.PersonalEvents })
-  for (const event of events) {
-    await tx.update(event, { space: (event.createdBy ?? event.modifiedBy) as string as Ref<Calendar> })
-  }
-  const space = await tx.findOne(calendar.class.Calendar, { _id: calendar.space.PersonalEvents })
-  if (space !== undefined) {
-    await tx.remove(space)
-  }
+async function migrateCalendars (client: MigrationClient): Promise<void> {
+  await client.move(
+    DOMAIN_SPACE,
+    { _class: { $in: [calendar.class.Calendar, calendar.class.ExternalCalendar] } },
+    DOMAIN_CALENDAR
+  )
+  await client.update(
+    DOMAIN_CALENDAR,
+    { _class: { $in: [calendar.class.Calendar, calendar.class.ExternalCalendar] } },
+    { space: calendar.space.Calendar }
+  )
+  await client.update(
+    DOMAIN_CALENDAR,
+    { _class: { $in: [calendar.class.Calendar, calendar.class.ExternalCalendar] }, archived: true },
+    { hidden: true }
+  )
+  await client.update(
+    DOMAIN_CALENDAR,
+    { _class: { $in: [calendar.class.Calendar, calendar.class.ExternalCalendar] }, archived: false },
+    { hidden: false }
+  )
+  await client.update(
+    DOMAIN_CALENDAR,
+    { _class: { $in: [calendar.class.Calendar, calendar.class.ExternalCalendar] } },
+    { $unset: { type: true, private: true, members: true, archived: true } }
+  )
 
-  const calendars = await tx.findAll(calendar.class.Calendar, { visibility: { $exists: false } })
-  for (const calendar of calendars) {
-    await tx.update(calendar, { visibility: 'public' })
-  }
-}
-
-async function migrateExternalCalendars (client: MigrationClient): Promise<void> {
-  const calendars = await client.find<Calendar>(DOMAIN_SPACE, { _class: calendar.class.Calendar })
-  const integrations = await client.find<Integration>(DOMAIN_SETTING, {
-    type: calendar.integrationType.Calendar,
-    disabled: false,
-    value: { $ne: '' }
+  const events = await client.find<Event>(DOMAIN_CALENDAR, {
+    space: { $ne: calendar.space.Calendar }
   })
-  for (const val of calendars) {
-    if (val._id.endsWith('_calendar')) continue
-    const integration = integrations.find((i) => i.createdBy === val.createdBy)
-    await client.update(
-      DOMAIN_SPACE,
-      { _id: val._id },
-      {
-        _class: calendar.class.ExternalCalendar,
-        externalId: val._id,
-        externalUser: integration?.value ?? '',
-        default: val._id === integration?.value
-      }
-    )
+  const eventByCalendar = new Map<Ref<Space>, Ref<Event>[]>()
+  for (const event of events) {
+    const events = eventByCalendar.get(event.space) ?? []
+    events.push(event._id)
+    eventByCalendar.set(event.space, events)
+  }
+  for (const [_calendar, ids] of eventByCalendar) {
+    await client.update(DOMAIN_CALENDAR, { _id: { $in: ids } }, { space: calendar.space.Calendar, calendar: _calendar })
   }
 }
 
@@ -148,23 +127,23 @@ export const calendarOperation: MigrateOperation = {
           await migrateReminders(client)
           await fillOriginalStartTime(client)
           await migrateSync(client)
-          await migrateExternalCalendars(client)
         }
       },
       {
         state: 'timezone',
         func: migrateTimezone
+      },
+      {
+        state: 'migrate_calendars',
+        func: migrateCalendars
       }
     ])
   },
   async upgrade (client: MigrationUpgradeClient): Promise<void> {
     await tryUpgrade(client, calendarId, [
       {
-        state: 'u-calendar0002',
-        func: async (client) => {
-          const tx = new TxOperations(client, core.account.System)
-          await migrateCalendars(tx)
-        }
+        state: 'default-space',
+        func: () => createDefaultSpace(client, calendar.space.Calendar, { name: 'Space for all events and calendars' })
       }
     ])
   }
diff --git a/plugins/calendar-resources/src/components/CalendarSelector.svelte b/plugins/calendar-resources/src/components/CalendarSelector.svelte
index e05727aa92..f3a8eafea3 100644
--- a/plugins/calendar-resources/src/components/CalendarSelector.svelte
+++ b/plugins/calendar-resources/src/components/CalendarSelector.svelte
@@ -16,7 +16,7 @@
   let calendars: ExternalCalendar[] = []
   const me = getCurrentAccount()
   const q = createQuery()
-  q.query(calendarPlugin.class.ExternalCalendar, { members: me._id, archived: false }, (res) => {
+  q.query(calendarPlugin.class.ExternalCalendar, { members: me._id, hidden: false }, (res) => {
     calendars = res
   })
 
diff --git a/plugins/calendar-resources/src/components/CalendarView.svelte b/plugins/calendar-resources/src/components/CalendarView.svelte
index 0fd0b76ed4..fa3e52cdb7 100644
--- a/plugins/calendar-resources/src/components/CalendarView.svelte
+++ b/plugins/calendar-resources/src/components/CalendarView.svelte
@@ -118,7 +118,7 @@
 
   let calendars: Calendar[] = []
 
-  calendarsQuery.query(calendar.class.Calendar, { members: me._id }, (res) => {
+  calendarsQuery.query(calendar.class.Calendar, { createdBy: me._id, hidden: false }, (res) => {
     calendars = res
   })
 
@@ -132,7 +132,7 @@
   ): void {
     q.query<Event>(
       _class,
-      query ?? { space: { $in: calendars.map((p) => p._id) } },
+      query ?? { calendar: { $in: calendars.map((p) => p._id) } },
       (result) => {
         raw = result
       },
@@ -257,11 +257,12 @@
           attachedToClass: dragItem._class,
           _class: dragEventClass,
           collection: 'events',
-          space: `${me._id}_calendar` as Ref<Calendar>,
+          calendar: `${me._id}_calendar` as Ref<Calendar>,
           modifiedBy: me._id,
           participants: [me.person],
           modifiedOn: Date.now(),
           date: e.detail.date.getTime(),
+          space: calendar.space.Calendar,
           dueDate: new Date(e.detail.date).setMinutes(new Date(e.detail.date).getMinutes() + 30)
         }
         raw.push(temp)
diff --git a/plugins/calendar-resources/src/components/CreateEvent.svelte b/plugins/calendar-resources/src/components/CreateEvent.svelte
index c5482740c0..e811eb49d8 100644
--- a/plugins/calendar-resources/src/components/CreateEvent.svelte
+++ b/plugins/calendar-resources/src/components/CreateEvent.svelte
@@ -65,12 +65,12 @@
   let description: Markup = EmptyMarkup
   let visibility: Visibility = 'private'
   const me = getCurrentAccount()
-  let space: Ref<Calendar> = `${me._id}_calendar` as Ref<Calendar>
+  let _calendar: Ref<Calendar> = `${me._id}_calendar` as Ref<Calendar>
 
   const q = createQuery()
-  q.query(calendar.class.ExternalCalendar, { default: true, members: me._id, archived: false }, (res) => {
+  q.query(calendar.class.ExternalCalendar, { default: true, members: me._id, hidden: false }, (res) => {
     if (res.length > 0) {
-      space = res[0]._id
+      _calendar = res[0]._id
     }
   })
 
@@ -93,27 +93,36 @@
     if (date === undefined) return
     if (title === '') return
     if (rules.length > 0) {
-      await client.addCollection(calendar.class.ReccuringEvent, space, attachedTo, attachedToClass, 'events', {
-        eventId: generateEventId(),
-        date: allDay ? saveUTC(date) : date,
-        dueDate: allDay ? saveUTC(dueDate) : dueDate,
-        externalParticipants,
-        rdate: [],
-        exdate: [],
-        rules,
-        reminders,
-        description,
-        participants,
-        visibility,
-        title,
-        location,
-        allDay,
-        access: 'owner',
-        originalStartTime: allDay ? saveUTC(date) : date,
-        timeZone
-      })
+      await client.addCollection(
+        calendar.class.ReccuringEvent,
+        calendar.space.Calendar,
+        attachedTo,
+        attachedToClass,
+        'events',
+        {
+          calendar: _calendar,
+          eventId: generateEventId(),
+          date: allDay ? saveUTC(date) : date,
+          dueDate: allDay ? saveUTC(dueDate) : dueDate,
+          externalParticipants,
+          rdate: [],
+          exdate: [],
+          rules,
+          reminders,
+          description,
+          participants,
+          visibility,
+          title,
+          location,
+          allDay,
+          access: 'owner',
+          originalStartTime: allDay ? saveUTC(date) : date,
+          timeZone
+        }
+      )
     } else {
-      await client.addCollection(calendar.class.Event, space, attachedTo, attachedToClass, 'events', {
+      await client.addCollection(calendar.class.Event, calendar.space.Calendar, attachedTo, attachedToClass, 'events', {
+        calendar: _calendar,
         eventId: generateEventId(),
         date: allDay ? saveUTC(date) : date,
         dueDate: allDay ? saveUTC(dueDate) : dueDate,
@@ -210,7 +219,7 @@
       />
     </div>
     <div class="block rightCropPadding">
-      <CalendarSelector bind:value={space} focusIndex={10101} />
+      <CalendarSelector bind:value={_calendar} focusIndex={10101} />
       <div class="flex-row-center flex-gap-1">
         <Icon icon={calendar.icon.Hidden} size={'small'} />
         <VisibilityEditor bind:value={visibility} kind={'tertiary'} focusIndex={10102} withoutIcon />
diff --git a/plugins/calendar-resources/src/components/CreateReminder.svelte b/plugins/calendar-resources/src/components/CreateReminder.svelte
index 611bc90fbd..99fdf7e035 100644
--- a/plugins/calendar-resources/src/components/CreateReminder.svelte
+++ b/plugins/calendar-resources/src/components/CreateReminder.svelte
@@ -44,8 +44,9 @@
     let date: number | undefined
     if (value != null) date = value
     if (date === undefined) return
-    const space = `${getCurrentAccount()._id}_calendar` as Ref<Calendar>
-    await client.addCollection(calendar.class.Event, space, attachedTo, attachedToClass, 'events', {
+    const _calendar = `${getCurrentAccount()._id}_calendar` as Ref<Calendar>
+    await client.addCollection(calendar.class.Event, calendar.space.Calendar, attachedTo, attachedToClass, 'events', {
+      calendar: _calendar,
       eventId: generateEventId(),
       date,
       dueDate: date + defaultDuration,
diff --git a/plugins/calendar-resources/src/components/EditEvent.svelte b/plugins/calendar-resources/src/components/EditEvent.svelte
index d5d6448904..d2bee0b77d 100644
--- a/plugins/calendar-resources/src/components/EditEvent.svelte
+++ b/plugins/calendar-resources/src/components/EditEvent.svelte
@@ -56,7 +56,7 @@
   let allDay = object.allDay
   let visibility = object.visibility ?? 'public'
   let reminders = [...(object.reminders ?? [])]
-  let space = object.space
+  let _calendar = object.calendar
   let timeZone: string = object.timeZone ?? getUserTimezone()
 
   let description = object.description
@@ -88,8 +88,8 @@
     if (object.visibility !== visibility) {
       update.visibility = visibility
     }
-    if (object.space !== space) {
-      update.space = space
+    if (object.calendar !== _calendar) {
+      update.calendar = _calendar
     }
     if (object.location !== location) {
       update.location = location
@@ -216,7 +216,7 @@
     </div>
     <div class="divider" />
     <div class="block rightCropPadding">
-      <CalendarSelector bind:value={space} focusIndex={10008} />
+      <CalendarSelector bind:value={_calendar} focusIndex={10008} />
       <div class="flex-row-center flex-gap-1">
         <Icon icon={calendar.icon.Hidden} size={'small'} />
         <VisibilityEditor bind:value={visibility} kind={'tertiary'} withoutIcon focusIndex={10009} />
diff --git a/plugins/calendar-resources/src/components/IntegrationConfigure.svelte b/plugins/calendar-resources/src/components/IntegrationConfigure.svelte
index 9e99f21291..314eda719b 100644
--- a/plugins/calendar-resources/src/components/IntegrationConfigure.svelte
+++ b/plugins/calendar-resources/src/components/IntegrationConfigure.svelte
@@ -40,7 +40,7 @@
 
   async function update (calendar: Calendar, value: boolean) {
     await client.update(calendar, {
-      archived: !value
+      hidden: !value
     })
   }
 
@@ -69,7 +69,7 @@
       {#each calendars as calendar}
         <div>{calendar.name}</div>
         <div>
-          <Toggle on={!calendar.archived} on:change={(res) => update(calendar, res.detail)} />
+          <Toggle on={!calendar.hidden} on:change={(res) => update(calendar, res.detail)} />
         </div>
       {/each}
     </Grid>
diff --git a/plugins/calendar-resources/src/index.ts b/plugins/calendar-resources/src/index.ts
index d35bd19e25..b9c3377965 100644
--- a/plugins/calendar-resources/src/index.ts
+++ b/plugins/calendar-resources/src/index.ts
@@ -90,6 +90,7 @@ async function deleteRecHandler (res: any, object: ReccuringInstance): Promise<v
         description: object.description,
         date: object.date,
         dueDate: object.dueDate,
+        calendar: object.calendar,
         allDay: object.allDay,
         participants: object.participants,
         externalParticipants: object.externalParticipants,
diff --git a/plugins/calendar-resources/src/utils.ts b/plugins/calendar-resources/src/utils.ts
index 2b9960405b..eb61914f80 100644
--- a/plugins/calendar-resources/src/utils.ts
+++ b/plugins/calendar-resources/src/utils.ts
@@ -37,8 +37,8 @@ export function hidePrivateEvents (events: Event[], calendars: IdMap<Calendar>,
           res.push(event)
         }
       } else {
-        const space = calendars.get(event.space)
-        if (space != null && space.visibility !== 'private') {
+        const calendar = calendars.get(event.calendar)
+        if (calendar != null && calendar.visibility !== 'private') {
           res.push(event)
         }
       }
@@ -62,11 +62,11 @@ export function isVisible (value: Event, calendars: IdMap<Calendar>): boolean {
   } else if (value.visibility === 'public') {
     return true
   }
-  const space = calendars.get(value.space)
-  if (space == null) {
+  const calendar = calendars.get(value.calendar)
+  if (calendar == null) {
     return true
   } else {
-    return space.visibility === 'public'
+    return calendar.visibility === 'public'
   }
 }
 
@@ -93,7 +93,7 @@ export async function updatePast (ops: DocumentUpdate<Event>, object: ReccuringI
   const client = getClient()
   const origin = await client.findOne(calendar.class.ReccuringEvent, {
     eventId: object.recurringEventId,
-    space: object.space
+    calendar: object.calendar
   })
   if (origin !== undefined) {
     await client.addCollection(
@@ -158,6 +158,7 @@ export async function updateReccuringInstance (
                   reminders: object.reminders,
                   location: object.location,
                   eventId: object.eventId,
+                  calendar: object.calendar,
                   access: 'owner',
                   rules: object.rules,
                   exdate: object.exdate,
@@ -170,7 +171,7 @@ export async function updateReccuringInstance (
               resolve(true)
             } else if (res.mode === 'all') {
               const base = await client.findOne(calendar.class.ReccuringEvent, {
-                space: object.space,
+                calendar: object.calendar,
                 eventId: object.recurringEventId
               })
               if (base !== undefined) {
diff --git a/plugins/calendar/src/index.ts b/plugins/calendar/src/index.ts
index de6611acfb..9fb0843751 100644
--- a/plugins/calendar/src/index.ts
+++ b/plugins/calendar/src/index.ts
@@ -12,7 +12,7 @@
 // limitations under the License.
 
 import { Contact } from '@hcengineering/contact'
-import type { AttachedDoc, Class, Doc, Markup, Mixin, Ref, Space, Timestamp } from '@hcengineering/core'
+import type { AttachedDoc, Class, Doc, Markup, Mixin, Ref, SystemSpace, Timestamp } from '@hcengineering/core'
 import { NotificationType } from '@hcengineering/notification'
 import type { Asset, IntlString, Metadata, Plugin } from '@hcengineering/platform'
 import { plugin } from '@hcengineering/platform'
@@ -27,7 +27,9 @@ export type Visibility = 'public' | 'freeBusy' | 'private'
 /**
  * @public
  */
-export interface Calendar extends Space {
+export interface Calendar extends Doc {
+  name: string
+  hidden: boolean
   visibility: Visibility
 }
 
@@ -76,11 +78,13 @@ export interface ReccuringEvent extends Event {
  * @public
  */
 export interface Event extends AttachedDoc {
-  space: Ref<Calendar>
+  space: Ref<SystemSpace>
   eventId: string
   title: string
   description: Markup
 
+  calendar: Ref<Calendar>
+
   location?: string
 
   allDay: boolean
@@ -161,8 +165,7 @@ const calendarPlugin = plugin(calendarId, {
     Permissions: '' as Asset
   },
   space: {
-    // deprecated
-    PersonalEvents: '' as Ref<Calendar>
+    Calendar: '' as Ref<SystemSpace>
   },
   app: {
     Calendar: '' as Ref<Doc>
diff --git a/plugins/time-resources/src/components/CreateToDoPopup.svelte b/plugins/time-resources/src/components/CreateToDoPopup.svelte
index 030447c179..e2acfa34a5 100644
--- a/plugins/time-resources/src/components/CreateToDoPopup.svelte
+++ b/plugins/time-resources/src/components/CreateToDoPopup.svelte
@@ -84,14 +84,15 @@
         rank: makeRank(undefined, latestTodo?.rank)
       }
     )
-    const space = `${acc._id}_calendar` as Ref<Calendar>
+    const _calendar = `${acc._id}_calendar` as Ref<Calendar>
     for (const slot of slots) {
-      await ops.addCollection(time.class.WorkSlot, space, id, time.class.ToDo, 'workslots', {
+      await ops.addCollection(time.class.WorkSlot, calendar.space.Calendar, id, time.class.ToDo, 'workslots', {
         eventId: generateEventId(),
         date: slot.date,
         dueDate: slot.dueDate,
         description: todo.description,
         participants: [acc.person],
+        calendar: _calendar,
         title: todo.title,
         allDay: false,
         access: 'owner',
@@ -107,12 +108,12 @@
   }
 
   const currentUser = getCurrentAccount() as PersonAccount
-  let space: Ref<Calendar> = `${currentUser._id}_calendar` as Ref<Calendar>
+  let _calendar: Ref<Calendar> = `${currentUser._id}_calendar` as Ref<Calendar>
 
   const q = createQuery()
   q.query(calendar.class.ExternalCalendar, { default: true, members: currentUser._id }, (res) => {
     if (res.length > 0) {
-      space = res[0]._id
+      _calendar = res[0]._id
     }
   })
 
@@ -142,7 +143,8 @@
       access: 'owner',
       visibility: todo.visibility,
       reminders: [],
-      space,
+      calendar: _calendar,
+      space: calendar.space.Calendar,
       _id: generateId(),
       _class: time.class.WorkSlot,
       attachedTo: generateId(),
diff --git a/plugins/time-resources/src/components/EditWorkSlot.svelte b/plugins/time-resources/src/components/EditWorkSlot.svelte
index 038e084594..ece40c1ea9 100644
--- a/plugins/time-resources/src/components/EditWorkSlot.svelte
+++ b/plugins/time-resources/src/components/EditWorkSlot.svelte
@@ -45,7 +45,7 @@
 
   let description = object.description
   let visibility = object.visibility ?? 'public'
-  let space = object.space
+  let _calendar = object.calendar
 
   let _doc: ToDo | undefined
 
@@ -84,8 +84,8 @@
     if (object.visibility !== visibility) {
       update.visibility = visibility
     }
-    if (object.space !== space) {
-      update.space = space
+    if (object.calendar !== _calendar) {
+      update.calendar = _calendar
     }
     if (!deepEqual(object.reminders, reminders)) {
       update.reminders = reminders
@@ -137,7 +137,7 @@
     <TaskSelector bind:value={_doc} focusIndex={10006} />
   </div>
   <div class="block rightCropPadding">
-    <CalendarSelector bind:value={space} disabled={readOnly} focusIndex={10007} />
+    <CalendarSelector bind:value={_calendar} disabled={readOnly} focusIndex={10007} />
     <div class="flex-row-center flex-gap-1">
       <Icon icon={calendar.icon.Hidden} size={'small'} />
       <VisibilityEditor bind:value={visibility} kind={'tertiary'} withoutIcon disabled={readOnly} focusIndex={10008} />
diff --git a/plugins/time-resources/src/components/PlanView.svelte b/plugins/time-resources/src/components/PlanView.svelte
index 18cba95f20..a3961fb8e8 100644
--- a/plugins/time-resources/src/components/PlanView.svelte
+++ b/plugins/time-resources/src/components/PlanView.svelte
@@ -53,12 +53,13 @@
     const currentUser = getCurrentAccount() as PersonAccount
     const extCalendar = await client.findOne(calendar.class.ExternalCalendar, {
       members: currentUser._id,
-      archived: false,
+      hidden: false,
       default: true
     })
-    const space = extCalendar ? extCalendar._id : (`${currentUser._id}_calendar` as Ref<Calendar>)
+    const _calendar = extCalendar ? extCalendar._id : (`${currentUser._id}_calendar` as Ref<Calendar>)
     const dueDate = date + defaultDuration
-    await client.addCollection(time.class.WorkSlot, space, doc._id, doc._class, 'workslots', {
+    await client.addCollection(time.class.WorkSlot, calendar.space.Calendar, doc._id, doc._class, 'workslots', {
+      calendar: _calendar,
       eventId: generateEventId(),
       date,
       dueDate,
diff --git a/plugins/time-resources/src/components/PlanningCalendar.svelte b/plugins/time-resources/src/components/PlanningCalendar.svelte
index 20bd21f1ae..9a337dcad3 100644
--- a/plugins/time-resources/src/components/PlanningCalendar.svelte
+++ b/plugins/time-resources/src/components/PlanningCalendar.svelte
@@ -55,7 +55,7 @@
   let calendars: Calendar[] = []
   let todayDate = new Date()
 
-  $: calendarsQ.query(calendar.class.Calendar, { members: acc, archived: false }, (res) => {
+  $: calendarsQ.query(calendar.class.Calendar, { createdBy: acc, hidden: false }, (res) => {
     calendars = res
   })
 
@@ -65,7 +65,7 @@
   function update (calendars: Calendar[]): void {
     q.query<Event>(
       calendar.class.Event,
-      { space: { $in: calendars.map((p) => p._id) } },
+      { calendar: { $in: calendars.map((p) => p._id) } },
       (result) => {
         raw = result
       },
@@ -115,7 +115,7 @@
         current.dueDate = new Date(e.detail.date).setMinutes(new Date(e.detail.date).getMinutes() + 30)
       } else {
         const me = getCurrentAccount() as PersonAccount
-        const space = `${me._id}_calendar` as Ref<Calendar>
+        const _calendar = `${me._id}_calendar` as Ref<Calendar>
         const ev: WorkSlot = {
           _id: dragItemId,
           allDay: false,
@@ -128,7 +128,8 @@
           _class: time.class.WorkSlot,
           collection: 'events',
           visibility: 'public',
-          space,
+          calendar: _calendar,
+          space: calendar.space.Calendar,
           modifiedBy: me._id,
           participants: [me.person],
           modifiedOn: Date.now(),
diff --git a/plugins/time-resources/src/components/TodoWorkslots.svelte b/plugins/time-resources/src/components/TodoWorkslots.svelte
index d4c7322353..4f6501215c 100644
--- a/plugins/time-resources/src/components/TodoWorkslots.svelte
+++ b/plugins/time-resources/src/components/TodoWorkslots.svelte
@@ -13,7 +13,7 @@
 // limitations under the License.
 -->
 <script lang="ts">
-  import { Calendar, generateEventId } from '@hcengineering/calendar'
+  import calendar, { Calendar, generateEventId } from '@hcengineering/calendar'
   import contact, { PersonAccount } from '@hcengineering/contact'
   import { Ref, getCurrentAccount } from '@hcengineering/core'
   import { createQuery, getClient } from '@hcengineering/presentation'
@@ -55,12 +55,13 @@
     const now = Date.now()
     const date = Math.ceil(now / (30 * 60 * 1000)) * (30 * 60 * 1000)
     const currentUser = getCurrentAccount() as PersonAccount
-    const space = `${currentUser._id}_calendar` as Ref<Calendar>
+    const _calendar = `${currentUser._id}_calendar` as Ref<Calendar>
     const dueDate = date + defaultDuration
-    await client.addCollection(time.class.WorkSlot, space, todo._id, todo._class, 'workslots', {
+    await client.addCollection(time.class.WorkSlot, calendar.space.Calendar, todo._id, todo._class, 'workslots', {
       eventId: generateEventId(),
       date,
       dueDate,
+      calendar: _calendar,
       description: todo.description,
       participants: [currentUser.person],
       title: todo.title,
diff --git a/plugins/time-resources/src/components/team/WithTeamData.svelte b/plugins/time-resources/src/components/team/WithTeamData.svelte
index 621e841721..1acaa0a65b 100644
--- a/plugins/time-resources/src/components/team/WithTeamData.svelte
+++ b/plugins/time-resources/src/components/team/WithTeamData.svelte
@@ -60,7 +60,7 @@
     calendar.class.Event,
     {
       _class: { $nin: [calendar.class.ReccuringEvent] },
-      space: { $in: calendarIds },
+      calendar: { $in: calendarIds },
       date: { $lte: toDate },
       dueDate: { $gte: fromDate },
       participants: { $in: persons } as any
@@ -72,7 +72,7 @@
 
   $: queryR.query(
     calendar.class.ReccuringEvent,
-    { space: { $in: calendarIds }, participants: { $in: persons } as any },
+    { calendar: { $in: calendarIds }, participants: { $in: persons } as any },
     (res) => {
       rawReq = res
     }
@@ -98,7 +98,7 @@
   )
 
   const calendarQuery = createQuery()
-  $: calendarQuery.query(calendar.class.Calendar, { archived: false }, (res) => {
+  $: calendarQuery.query(calendar.class.Calendar, { hidden: false }, (res) => {
     calendarIds = res.map((p) => p._id)
     calendars = toIdMap(res)
   })
diff --git a/plugins/time-resources/src/components/team/utils.ts b/plugins/time-resources/src/components/team/utils.ts
index e5aab8711c..21cc80f703 100644
--- a/plugins/time-resources/src/components/team/utils.ts
+++ b/plugins/time-resources/src/components/team/utils.ts
@@ -91,15 +91,11 @@ export function groupTeamData (
   }
 
   for (const event of events) {
-    const space = calendars.get(event.space)
-    if (space === undefined) {
+    const _calendar = calendars.get(event.calendar)
+    if (_calendar === undefined) {
       continue
     }
     for (const p of event.participants) {
-      const accounts = personAccounts.filter((it) => it.person === p)
-      if (!accounts.some((it) => space.members.includes(it._id))) {
-        continue
-      }
       const mapping: EventPersonMapping = result.get(p) ?? {
         busy: {
           slots: [],
diff --git a/server-plugins/calendar-resources/src/index.ts b/server-plugins/calendar-resources/src/index.ts
index d89c0546ee..a912e3a298 100644
--- a/server-plugins/calendar-resources/src/index.ts
+++ b/server-plugins/calendar-resources/src/index.ts
@@ -15,7 +15,7 @@
 
 import calendar, { Calendar, Event } from '@hcengineering/calendar'
 import { PersonAccount } from '@hcengineering/contact'
-import core, {
+import {
   Class,
   Doc,
   DocumentQuery,
@@ -85,13 +85,10 @@ export async function OnPersonAccountCreate (tx: Tx, control: TriggerControl): P
 
   const res: TxCreateDoc<Calendar> = control.txFactory.createTxCreateDoc(
     calendar.class.Calendar,
-    core.space.Space,
+    calendar.space.Calendar,
     {
       name: user.email,
-      description: '',
-      archived: false,
-      private: false,
-      members: [user._id],
+      hidden: false,
       visibility: 'public'
     },
     `${user._id}_calendar` as Ref<Calendar>,