diff --git a/desk/app/contacts.hoon b/desk/app/contacts.hoon
index 189fcb7..74c7b1f 100644
--- a/desk/app/contacts.hoon
+++ b/desk/app/contacts.hoon
@@ -1,3 +1,4 @@
+/-  activity
 /+  default-agent, dbug, verb, neg=negotiate
 /+  *contacts
 ::
@@ -100,6 +101,12 @@
   ::
   +|  %operations
   ::
+  ++  pass-activity
+    |=  [who=ship field=(pair @tas value)]
+    ^-  card
+    =/  =cage  activity-action+!>(`action:activity`[%add %contact who field])
+    [%pass /activity %agent [our.bowl %activity] %poke cage]
+  ::
   ::  +pub: publication management
   ::
   ::    - /v1/news: local updates to our profile and rolodex
@@ -344,15 +351,43 @@
           cor  =.  cor
                (p-news-0:pub who (contact:to-0 con.u))
                =/  page=(unit page)  (~(get by book) who)
-               ::  update peer contact page
+               ::  update contact book and send notification
                ::
                =?  cor  ?=(^ page)
                  ?:  =(con.u.page con.u)  cor
                  =.  book  (~(put by book) who u.page(con con.u))
+                 =.  cor  (emil (send-activity u con.u.page))
                  (p-response:pub %page who con.u mod.u.page)
                (p-response:pub %peer who con.u)
         ==
       ::
+      ++  send-activity
+        |=  [u=update con=contact]
+        ^-  (list card)
+        ?.  .^(? %gu /(scot %p our.bowl)/activity/(scot %da now.bowl)/$)
+          ~
+        %-  ~(rep by con.u)
+        |=  [field=(pair @tas value) cards=(list card)]
+        ?>  ?=(^ q.field)
+        ::  do not broadcast empty changes
+        ::
+        ?:  (is-value-empty q.field) 
+          cards
+        ::
+        =/  val=(unit value)  (~(get by con) p.field)
+        ?~  val
+          [(pass-activity who field) cards]
+        ?<  ?=(~ u.val)
+        ::NOTE  currently shouldn't happen in practice 
+        ?.  =(-.q.field -.u.val)  cards
+        ?:  =(p.q.field p.u.val)  cards
+        ?.  ?=(%set -.q.field)
+          [(pass-activity who field) cards]
+        =/  diff=(set value)
+          (~(dif in p.q.field) ?>(?=(%set -.u.val) p.u.val))
+        ?~  diff  cards
+        [(pass-activity who p.field set+diff) cards]
+      ::
       ++  si-meet
         ^+  si-cor
         ::
@@ -735,7 +770,7 @@
   ++  agent
     |=  [=wire =sign:agent:gall]
     ^+  cor
-    ?+  wire  ~|(evil-agent+wire !!)
+    ?+    wire  ~|(evil-agent+wire !!)
         [%contact ~]
       si-abet:(si-take:(sub src.bowl) wire sign)
       ::
@@ -744,6 +779,9 @@
       ?~  p.sign  cor
       %-  (slog leaf/"{<wire>} failed" u.p.sign)
       cor
+      ::
+        [%activity ~]
+      cor
       ::
         [%epic ~]
       cor
diff --git a/desk/lib/contacts.hoon b/desk/lib/contacts.hoon
index 853b619..be6afe1 100644
--- a/desk/lib/contacts.hoon
+++ b/desk/lib/contacts.hoon
@@ -2,6 +2,16 @@
 |%
 ::
 +|  %contact
+::  +is-value-empty: is value considered empty
+::
+++  is-value-empty
+  |=  val=value
+  ^-  ?
+  ?+  -.val  |
+    %text  =('' p.val)
+    %look  =('' p.val)
+    %set   ?=(~ p.val)
+  ==
 ::  +cy: contact map engine
 ::
 ++  cy
diff --git a/desk/lib/contacts/json-1.hoon b/desk/lib/contacts/json-1.hoon
index cbf368e..a65fc33 100644
--- a/desk/lib/contacts/json-1.hoon
+++ b/desk/lib/contacts/json-1.hoon
@@ -112,8 +112,7 @@
   ++  value
     ^-  $-(json value:c)
     |=  jon=json
-    ::  XX is there a way to do it in one go?
-    ::
+    ?~  jon  ~
     =/  [type=@tas val=json]
       %.  jon
       (ot type+(se %tas) value+json ~)
diff --git a/desk/sur/activity.hoon b/desk/sur/activity.hoon
new file mode 100644
index 0000000..8f5d1f0
--- /dev/null
+++ b/desk/sur/activity.hoon
@@ -0,0 +1,368 @@
+/-  c=channels, t=contacts, ch=chat, g=groups
+/+  mp=mop-extensions
+|%
++|  %collections
+::  $stream: the activity stream comprised of events from various agents
++$  stream  ((mop time event) lte)
+::  $indices: the stream and its read data split into various indices
++$  indices
+  $~  [[[%base ~] *index] ~ ~]
+  (map source index)
+::  $volume-settings: the volume settings for each source
++$  volume-settings  (map source volume-map)
+::  $activity: the current state of activity for each source
++$  activity  (map source activity-summary)
+::  $full-info: the full state of the activity stream
++$  full-info  [=indices =activity =volume-settings]
+::  $volume-map: how to badge and notify for each event type
++$  volume-map
+  $~  default-volumes
+  (map event-type volume)
+::  $feed: a set of grouped events and the summaries of their sources
++$  feed
+  $:  feed=(list activity-bundle)
+      summaries=activity
+  ==
++$  feed-init
+  $:  all=(list activity-bundle)
+      mentions=(list activity-bundle)
+      replies=(list activity-bundle)
+      summaries=activity
+  ==
++|  %actions
+::  $action: how to interact with our activity stream
+::
+::    actions are only ever performed for and by our selves
+::
+::    %add: add an event to the stream
+::    %bump: mark a source as having new activity from myself
+::    %del: remove a source and all its activity
+::    %read: mark an event as read
+::    %adjust: adjust the volume of an source
+::    %allow-notifications: change which notifications are allowed
+::
++$  action
+  $%  [%add =incoming-event]
+      [%bump =source]
+      [%del =source]
+      [%del-event =source event=incoming-event]
+      [%read =source =read-action]
+      [%adjust =source =(unit volume-map)]
+      [%allow-notifications allow=notifications-allowed]
+  ==
+::
+::  $read-action: mark activity read
+::
+::    %item: (DEPRECATED) mark an individual activity as read, indexed by id
+::    %event: (DEPRECATED) mark an individual activity as read, indexed by the event itself
+::    %all: mark _everything_ as read for this source, and possibly children
+::
++$  read-action
+  $%  [%item id=time-id]
+      [%event event=incoming-event]
+      [%all time=(unit time) deep=?]
+  ==
+::
++|  %updates
+::
+::  $update: what we hear after an action
+::
+::    %add: an event was added to the stream
+::    %del: a source and its activity were removed
+::    %read: a source's activity state was updated
+::    %activity: the activity state was updated
+::    %adjust: the volume of a source was adjusted
+::    %allow-notifications: the allowed notifications were changed
+::
++$  update
+  $%  [%add =source time-event]
+      [%del =source]
+      [%read =source =activity-summary]
+      [%activity =activity]
+      [%adjust =source volume-map=(unit volume-map)]
+      [%allow-notifications allow=notifications-allowed]
+  ==
+::
++|  %basics
+::  $event: a single point of activity, from one of our sources
+::
+::    $incoming-event: the event that was sent to us
+::    .notified: if this event has been notified
+::    .child: if this event is from a child source
+::
++$  event
+  $:  incoming-event
+      notified=?
+      child=?
+  ==
++$  incoming-event
+  $%  [%post post-event]
+      [%reply reply-event]
+      [%dm-invite =whom]
+      [%dm-post dm-post-event]
+      [%dm-reply dm-reply-event]
+      [%group-ask group=flag:g =ship]
+      [%group-kick group=flag:g =ship]
+      [%group-join group=flag:g =ship]
+      [%group-invite group=flag:g =ship]
+      [%chan-init channel=nest:c group=flag:g]
+      [%group-role group=flag:g =ship roles=(set sect:g)]
+      [%flag-post key=message-key channel=nest:c group=flag:g]
+      [%flag-reply key=message-key parent=message-key channel=nest:c group=flag:g]
+      [%contact contact-event]
+  ==
+::
++$  post-event
+  $:  key=message-key
+      channel=nest:c
+      group=flag:g
+      content=story:c
+      mention=?
+  ==
+::
++$  reply-event
+  $:  key=message-key
+      parent=message-key
+      channel=nest:c
+      group=flag:g
+      content=story:c
+      mention=?
+  ==
+::
++$  dm-post-event
+  $:  key=message-key
+      =whom
+      content=story:c
+      mention=?
+  ==
+::
++$  dm-reply-event
+  $:  key=message-key
+      parent=message-key
+      =whom
+      content=story:c
+      mention=?
+  ==
+::
++$  contact-event
+  $:  who=ship
+      update=(pair @tas value:t)
+  ==
+::
+::  $source: where the activity is happening
++$  source
+  $%  [%base ~]
+      [%group =flag:g]
+      [%channel =nest:c group=flag:g]
+      [%thread key=message-key channel=nest:c group=flag:g]
+      [%dm =whom]
+      [%dm-thread key=message-key =whom]
+      [%contact who=ship]
+  ==
+::
+::  $index: the stream of activity and read state for a source
++$  index  [=stream =reads bump=time]
+::
+::  $reads: the read state for a source
+::
+::    $floor: the time of the latest event that was read
+::    $items: the set of events above the floor that have been read
+::
++$  reads
+  $:  floor=time
+      items=read-items
+  ==
++$  read-items  ((mop time-id ,~) lte)
+::  $activity-summary: the summary of activity for a source
+::
+::    $newest: the time of the latest activity read or unread
+::    $count: the total number of unread events including children
+::    $notify-count: the number of unreads that are notifications
+::                   including children
+::    $notify: if there are any notifications here or in children
+::    $unread: if the main stream of source is unread: which starting
+::             message, how many there are, and if any are notifications
+::    $children: the sources nested under this source
+::
++$  activity-summary
+  $~  [*@da 0 0 | ~ ~ ~]
+  $:  newest=time
+      count=@ud
+      notify-count=@ud
+      notify=_|
+      unread=(unit unread-point)
+      children=(set source)
+      reads=*  ::  DO NOT USE, 🚨 ⚠️ REMOVE
+  ==
++$  unread-point  [message-key count=@ud notify=_|]
++$  volume  [unreads=? notify=?]
++$  notifications-allowed  ?(%all %some %none)
++$  activity-bundle
+  $:  =source
+      latest=time
+      events=(list time-event)
+  ==
+::
++|  %primitives
++$  whom
+  $%  [%ship p=ship]
+      [%club p=id:club:ch]
+  ==
++$  time-id  time
++$  message-id   (pair ship time-id)
++$  message-key  [id=message-id =time]
+::
++$  event-type
+  $?  %chan-init
+      %post
+      %post-mention
+      %reply
+      %reply-mention
+      %dm-invite
+      %dm-post
+      %dm-post-mention
+      %dm-reply
+      %dm-reply-mention
+      %group-invite
+      %group-kick
+      %group-join
+      %group-ask
+      %group-role
+      %flag-post
+      %flag-reply
+      %contact
+  ==
++|  %helpers
++$  time-event  [=time =event]
+++  on-event        ((on time event) lte)
+++  ex-event        ((mp time event) lte)
+++  on-read-items   ((on time ,~) lte)
++|  %constants
+++  default-volumes
+  ^~
+  ^-  (map event-type volume)
+  %-  my
+  :~  [%post & &]
+      [%reply & |]
+      [%dm-reply & &]
+      [%post-mention & &]
+      [%reply-mention & &]
+      [%dm-invite & &]
+      [%dm-post & &]
+      [%dm-post-mention & &]
+      [%dm-reply-mention & &]
+      [%group-invite & &]
+      [%group-ask & &]
+      [%flag-post & &]
+      [%flag-reply & &]
+      [%group-kick & |]
+      [%group-join & |]
+      [%group-role & |]
+      ::XX remove notify?
+      [%contact & &]
+  ==
+++  old-volumes
+  ^~
+  %-  my
+  :~  [%soft (~(put by default-volumes) %post [& |])]
+      [%loud (~(run by default-volumes) |=([u=? *] [u &]))]
+      [%hush (~(run by default-volumes) |=([u=? *] [u |]))]
+  ==
+++  mute
+  ^~
+  (~(run by default-volumes) |=(* [| |]))
+::
++|  %old-types
+++  old
+  |%
+  ++  v7
+    |%
+    +$  stream  ((mop time event) lte)
+    +$  event
+      $:  incoming-event
+          notified=?
+          child=?
+      ==
+    +$  incoming-event
+      $%  [%post post-event]
+          [%reply reply-event]
+          [%dm-invite =whom]
+          [%dm-post dm-post-event]
+          [%dm-reply dm-reply-event]
+          [%group-ask group=flag:g =ship]
+          [%group-kick group=flag:g =ship]
+          [%group-join group=flag:g =ship]
+          [%group-invite group=flag:g =ship]
+          [%chan-init channel=nest:c group=flag:g]
+          [%group-role group=flag:g =ship roles=(set sect:g)]
+          [%flag-post key=message-key channel=nest:c group=flag:g]
+          [%flag-reply key=message-key parent=message-key channel=nest:c group=flag:g]
+      ==
+    +$  source
+      $%  [%base ~]
+          [%group =flag:g]
+          [%channel =nest:c group=flag:g]
+          [%thread key=message-key channel=nest:c group=flag:g]
+          [%dm =whom]
+          [%dm-thread key=message-key =whom]
+      ==
+    +$  index  [=stream =reads bump=time]
+    --
+  ++  v4
+    |%
+    +$  feed  (list activity-bundle)
+    --
+  ++  v3
+    |%
+    +$  index  [=stream =reads]
+    +$  indices  (map source index)
+    +$  update
+      $%  [%add =source time-event]
+          [%del =source]
+          [%read =source =activity-summary]
+          [%adjust =source volume-map=(unit volume-map)]
+          [%allow-notifications allow=notifications-allowed]
+      ==
+    +$  full-info
+      $:  =indices
+          =activity
+          =volume-settings
+      ==
+    +$  activity  (map source activity-summary)
+    +$  activity-summary
+      $~  [*@da 0 0 | ~ ~ [*@da ~]]
+      $:  newest=time
+          count=@ud
+          notify-count=@ud
+          notify=_|
+          unread=(unit unread-point)
+          children=(unit activity)
+          =reads
+      ==
+    --
+  ++  v2
+    |%
+    +$  update
+      $%  [%add =source time-event]
+          [%del =source]
+          [%read =source =activity-summary]
+          [%adjust =source volume-map=(unit volume-map)]
+          [%allow-notifications allow=notifications-allowed]
+      ==
+    +$  full-info
+      $:  =indices:v3
+          activity=activity
+          =volume-settings
+      ==
+    +$  activity  (map source activity-summary)
+    +$  activity-summary
+      $~  [*@da 0 | ~ ~]
+      $:  newest=time
+          count=@ud
+          notify=_|
+          unread=(unit unread-point)
+          children=(unit activity)
+      ==
+    --
+  --
+--
diff --git a/desk/sur/contacts-0.hoon b/desk/sur/contacts-0.hoon
index a019da8..91ba0d3 100644
--- a/desk/sur/contacts-0.hoon
+++ b/desk/sur/contacts-0.hoon
@@ -57,4 +57,19 @@
 ::
 +$  news-0
   [who=ship con=$@(~ contact-0)]
+::
+++  get-contact
+  |=  [=bowl:gall who=@p]
+  =>  :_  ..get-contact
+      [who=who our=our.bowl now=now.bowl]
+  ~+  ^-  (unit contact-0)
+  =/  base=path  /(scot %p our)/contacts/(scot %da now)
+  ?.  ~+  .^(? %gu (weld base /$))
+    ~
+  =+  ~+  .^(rol=rolodex %gx (weld base /all/contact-rolodex))
+  ?~  for=(~(get by rol) who)
+    ~
+  ?.  ?=([[@ ^] *] u.for)
+    ~
+  `con.for.u.for
 --