diff --git a/lib/Activity/Deprecated/Provider.php b/lib/Activity/Deprecated/Provider.php
new file mode 100644
index 000000000..1ea994f62
--- /dev/null
+++ b/lib/Activity/Deprecated/Provider.php
@@ -0,0 +1,213 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Circles\Activity\Deprecated;
+
+use OCA\Circles\AppInfo\Application;
+use OCA\Circles\Exceptions\FakeException;
+use OCA\Circles\Model\Circle;
+use OCA\Circles\Model\Member;
+use OCA\Circles\Tools\Exceptions\InvalidItemException;
+use OCA\Circles\Tools\Traits\TDeserialize;
+use OCP\Activity\Exceptions\UnknownActivityException;
+use OCP\Activity\IEvent;
+use OCP\Activity\IManager;
+use OCP\Activity\IProvider;
+use OCP\IURLGenerator;
+
+class Provider implements IProvider {
+	use TDeserialize;
+
+	public function __construct(
+		private IManager $activityManager,
+		private IURLGenerator $urlGenerator,
+		private ProviderSubjectCircle $parserCircle,
+		private ProviderSubjectMember $parserMember,
+		private ProviderSubjectCircleMember $parserCircleMember,
+	) {
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function parse($language, IEvent $event, ?IEvent $previousEvent = null): IEvent {
+		try {
+			$params = $event->getSubjectParameters();
+			$this->initActivityParser($event, $params);
+
+			/** @var Circle $circle */
+			$circle = $this->deserializeJson($params['circle'], Circle::class);
+
+			$this->setIcon($event);
+			$this->parseAsNonMember($event, $circle);
+			$this->parseAsMember($event, $circle, $params);
+			$this->parseAsModerator($event, $circle, $params);
+		} catch (FakeException|InvalidItemException $e) {
+			/** clean exit */
+		}
+
+		return $event;
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param array $params
+	 */
+	private function initActivityParser(IEvent $event, array $params): void {
+		if ($event->getApp() !== Application::APP_ID) {
+			throw new UnknownActivityException();
+		}
+
+		if (!key_exists('circle', $params)) {
+			throw new UnknownActivityException();
+		}
+	}
+
+	/**
+	 * @param IEvent $event
+	 */
+	private function setIcon(IEvent $event): void {
+		$path = $this->urlGenerator->imagePath(Application::APP_ID, 'circles.svg');
+		$event->setIcon($this->urlGenerator->getAbsoluteURL($path));
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param array $params
+	 *
+	 * @throws FakeException
+	 */
+	private function parseAsNonMember(
+		IEvent $event,
+		Circle $circle,
+	): void {
+		if ($event->getType() !== 'circles_as_non_member') {
+			return;
+		}
+
+		$this->parserCircle->parseSubjectCircleCreate($event, $circle);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param array $params
+	 *
+	 * @throws FakeException
+	 */
+	private function parseAsMember(
+		IEvent $event,
+		Circle $circle,
+		array $params,
+	): void {
+		if ($event->getType() !== 'circles_as_member') {
+			return;
+		}
+
+		$this->parserCircle->parseSubjectCircleCreate($event, $circle);
+		$this->parserCircle->parseSubjectCircleDelete($event, $circle);
+		$this->parseMemberAsMember($event, $circle, $params);
+		$this->parseCircleMemberAsMember($event, $circle, $params);
+	}
+
+	/**
+	 * @param Circle $circle
+	 * @param IEvent $event
+	 * @param array $params
+	 *
+	 * @throws FakeException
+	 * @throws InvalidItemException
+	 */
+	private function parseAsModerator(IEvent $event, Circle $circle, array $params): void {
+		if ($event->getType() !== 'circles_as_moderator') {
+			return;
+		}
+
+		$this->parseMemberAsModerator($event, $circle, $params);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param array $params
+	 *
+	 * @throws FakeException
+	 * @throws InvalidItemException
+	 */
+	private function parseMemberAsMember(
+		IEvent $event,
+		Circle $circle,
+		array $params,
+	): void {
+		if (!key_exists('member', $params)) {
+			return;
+		}
+
+		/** @var Member $member */
+		$member = $this->deserializeJson($params['member'], Member::class);
+
+		$this->parserMember->parseSubjectMemberJoin($event, $circle, $member);
+		$this->parserMember->parseSubjectMemberAdd($event, $circle, $member);
+		$this->parserMember->parseSubjectMemberLeft($event, $circle, $member);
+		$this->parserMember->parseSubjectMemberRemove($event, $circle, $member);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param array $params
+	 *
+	 * @throws FakeException
+	 * @throws InvalidItemException
+	 */
+	private function parseCircleMemberAsMember(
+		IEvent $event,
+		Circle $circle,
+		array $params,
+	): void {
+		if (!key_exists('member', $params)) {
+			return;
+		}
+
+		/** @var Member $member */
+		$member = $this->deserializeJson($params['member'], Member::class);
+
+		$this->parserCircleMember->parseSubjectCircleMemberJoin($event, $circle, $member);
+		$this->parserCircleMember->parseSubjectCircleMemberAdd($event, $circle, $member);
+		$this->parserCircleMember->parseSubjectCircleMemberLeft($event, $circle, $member);
+		$this->parserCircleMember->parseSubjectCircleMemberRemove($event, $circle, $member);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param array $params
+	 *
+	 * @throws FakeException
+	 * @throws InvalidItemException
+	 */
+	private function parseMemberAsModerator(
+		IEvent $event,
+		Circle $circle,
+		array $params,
+	): void {
+		if (!key_exists('member', $params)) {
+			return;
+		}
+
+		/** @var Member $member */
+		$member = $this->deserializeJson($params['member'], Member::class);
+
+		$this->parserMember->parseMemberInvited($event, $circle, $member);
+		$this->parserMember->parseMemberLevel($event, $circle, $member, $params['level'] ?? 0);
+		$this->parserMember->parseMemberRequestInvitation($event, $circle, $member);
+		$this->parserMember->parseMemberOwner($event, $circle, $member);
+	}
+}
diff --git a/lib/Activity/Deprecated/ProviderParser.php b/lib/Activity/Deprecated/ProviderParser.php
new file mode 100644
index 000000000..ac5e2514c
--- /dev/null
+++ b/lib/Activity/Deprecated/ProviderParser.php
@@ -0,0 +1,301 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Circles\Activity\Deprecated;
+
+use OCA\Circles\IFederatedUser;
+use OCA\Circles\Model\Circle;
+use OCA\Circles\Model\Member;
+use OCP\Activity\IEvent;
+use OCP\Activity\IManager;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+
+class ProviderParser {
+	public function __construct(
+		protected IURLGenerator $url,
+		protected IManager $activityManager,
+		protected IL10N $l10n,
+	) {
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param string $ownEvent
+	 * @param string $othersEvent
+	 */
+	protected function parseCircleEvent(
+		IEvent $event,
+		Circle $circle,
+		string $ownEvent,
+		string $othersEvent,
+	): void {
+		$data = [
+			'author' => $this->generateViewerParameter($circle),
+			'circle' => $this->generateCircleParameter($circle)
+		];
+
+		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+			$this->setSubject($event, $ownEvent, $data);
+
+			return;
+		}
+
+		$this->setSubject($event, $othersEvent, $data);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param string $line
+	 * @param array<string, array<string, mixed>> $data
+	 */
+	protected function setSubject(
+		IEvent $event,
+		string $line,
+		array $data,
+	): void {
+		$this->setParsedSubject($event, $line, $data);
+		$this->setRichSubject($event, $line, $data);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param string $line
+	 * @param array<string, array<string, mixed>> $data
+	 */
+	protected function setRichSubject(
+		IEvent $event,
+		string $line,
+		array $data,
+	): void {
+		$ak = array_keys($data);
+		foreach ($ak as $k) {
+			$subAk = array_keys($data[$k]);
+			foreach ($subAk as $sK) {
+				if (str_starts_with($sK, '_')) {
+					unset($data[$k][$sK]);
+				}
+			}
+		}
+
+		$event->setRichSubject($line, $data);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param string $line
+	 * @param array $data
+	 */
+	protected function setParsedSubject(
+		IEvent $event,
+		string $line,
+		array $data,
+	): void {
+		$ak = array_keys($data);
+		$replace = [];
+		foreach ($ak as $k) {
+			if (!key_exists('_parsed', $data[$k])) {
+				continue;
+			}
+
+			$replace['{' . $k . '}'] = $data[$k]['_parsed'];
+		}
+
+		$event->setParsedSubject(strtr($line, $replace));
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @param string $ownEvent
+	 * @param string $othersEvent
+	 */
+	protected function parseMemberEvent(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+		string $ownEvent,
+		string $othersEvent,
+	): void {
+		$data = [
+			'circle' => $this->generateCircleParameter($circle),
+			'member' => $this->generateUserParameter($member)
+		];
+
+		if ($member->getUserId() === $this->activityManager->getCurrentUserId()
+		) {
+			$this->setSubject($event, $ownEvent, $data);
+
+			return;
+		}
+
+		$this->setSubject($event, $othersEvent, $data);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @param string $ownEvent
+	 * @param string $othersEvent
+	 */
+	protected function parseCircleMemberEvent(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+		string $ownEvent,
+		string $othersEvent,
+	): void {
+		$data = [
+			'author' => $this->generateViewerParameter($circle),
+			'circle' => $this->generateCircleParameter($circle),
+			'member' => $this->generateUserParameter($member),
+			'external' => $this->generateExternalMemberParameter($member),
+			'group' => $this->generateGroupParameter($member),
+		];
+
+		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+			$this->setSubject($event, $ownEvent, $data);
+
+			return;
+		}
+
+		$this->setSubject($event, $othersEvent, $data);
+	}
+
+	/**
+	 * general function to generate Circle+Member advanced event.
+	 *
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @param string $ownEvent
+	 * @param string $targetEvent
+	 * @param string $othersEvent
+	 */
+	protected function parseCircleMemberAdvancedEvent(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+		string $ownEvent,
+		string $targetEvent,
+		string $othersEvent,
+	): void {
+		$data = [
+			'author' => $this->generateViewerParameter($circle),
+			'circle' => $this->generateCircleParameter($circle),
+			'member' => $this->generateUserParameter($member)
+		];
+
+		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+			$this->setSubject($event, $ownEvent, $data);
+
+			return;
+		}
+
+		if ($member->getUserId() === $this->activityManager->getCurrentUserId()) {
+			$this->setSubject($event, $targetEvent, $data);
+
+			return;
+		}
+
+		$this->setSubject($event, $othersEvent, $data);
+	}
+
+	/**
+	 * @param Circle $circle
+	 * @param string $userId
+	 *
+	 * @return bool
+	 */
+	protected function isViewerTheAuthor(Circle $circle, string $userId): bool {
+		if (!$circle->hasInitiator()) {
+			return false;
+		}
+
+		$initiator = $circle->getInitiator();
+
+		return ($initiator->getUserType() === Member::TYPE_USER
+			&& $initiator->getUserId() === $userId);
+	}
+
+	/**
+	 * @param Circle $circle
+	 *
+	 * @return array <string,string|integer>
+	 */
+	protected function generateViewerParameter(Circle $circle): array {
+		if (!$circle->hasInitiator()) {
+			return [];
+		}
+
+		return $this->generateUserParameter($circle->getInitiator());
+	}
+
+	/**
+	 * @param Member $member
+	 *
+	 * @return array <string,string|integer>
+	 */
+	protected function generateExternalMemberParameter(Member $member): array {
+		return [
+			'type' => 'email',
+			'id' => $member->getUserId(),
+			'link' => '',
+			'name' => $member->getDisplayName(),
+			'_parsed' => $member->getDisplayName()
+		];
+	}
+
+	/**
+	 * @param Circle $circle
+	 *
+	 * @return array<string,string|integer>
+	 */
+	protected function generateCircleParameter(Circle $circle): array {
+		return [
+			'type' => 'circle',
+			'id' => $circle->getSingleId(),
+			'name' => $circle->getName(),
+			'_parsed' => $circle->getName(),
+			'link' => $this->url->getAbsoluteURL($circle->getUrl()),
+		];
+	}
+
+	/**
+	 * @return array <string,string|integer>
+	 */
+	protected function generateUserParameter(IFederatedUser $member): array {
+		$display = $member->getDisplayName();
+		if ($display === '') {
+			$display = $member->getUserId();
+		}
+
+		return [
+			'type' => 'user',
+			'id' => $member->getUserId(),
+			'name' => $display,
+			'_parsed' => $display
+		];
+	}
+
+	/**
+	 * @return array <string,string|integer>
+	 */
+	protected function generateGroupParameter(Member $group): array {
+		return [
+			'type' => 'user-group',
+			'id' => $group->getUserId(),
+			'name' => $group->getUserId(),
+			'_parsed' => $group->getUserId()
+		];
+	}
+}
diff --git a/lib/Activity/Deprecated/ProviderSubjectCircle.php b/lib/Activity/Deprecated/ProviderSubjectCircle.php
new file mode 100644
index 000000000..9581efea2
--- /dev/null
+++ b/lib/Activity/Deprecated/ProviderSubjectCircle.php
@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Circles\Activity\Deprecated;
+
+use OCA\Circles\Exceptions\FakeException;
+use OCA\Circles\Model\Circle;
+use OCP\Activity\IEvent;
+
+class ProviderSubjectCircle extends ProviderParser {
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 *
+	 * @throws FakeException
+	 */
+	public function parseSubjectCircleCreate(IEvent $event, Circle $circle): void {
+		if ($event->getSubject() !== 'circle_create') {
+			return;
+		}
+
+		$this->parseCircleEvent(
+			$event, $circle,
+			$this->l10n->t('You created the team {circle}'),
+			$this->l10n->t('{author} created the team {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 *
+	 * @throws FakeException
+	 */
+	public function parseSubjectCircleDelete(IEvent $event, Circle $circle): void {
+		if ($event->getSubject() !== 'circle_delete') {
+			return;
+		}
+
+		$this->parseCircleEvent(
+			$event, $circle,
+			$this->l10n->t('You deleted {circle}'),
+			$this->l10n->t('{author} deleted {circle}')
+		);
+
+		throw new FakeException();
+	}
+}
diff --git a/lib/Activity/Deprecated/ProviderSubjectCircleMember.php b/lib/Activity/Deprecated/ProviderSubjectCircleMember.php
new file mode 100644
index 000000000..f991ca40d
--- /dev/null
+++ b/lib/Activity/Deprecated/ProviderSubjectCircleMember.php
@@ -0,0 +1,148 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Circles\Activity\Deprecated;
+
+use OCA\Circles\Exceptions\FakeException;
+use OCA\Circles\Model\Circle;
+use OCA\Circles\Model\Member;
+use OCP\Activity\IEvent;
+
+class ProviderSubjectCircleMember extends ProviderParser {
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @param string $ownEvent
+	 * @param string $othersEvent
+	 * @return void
+	 */
+	protected function parseMemberCircleEvent(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+		string $ownEvent,
+		string $othersEvent,
+	): void {
+		$data = [
+			'author' => $this->generateViewerParameter($circle),
+			'circle' => $this->generateCircleParameter($circle),
+			'member' => $this->generateUserParameter($member),
+			'external' => $this->generateExternalMemberParameter($member),
+			'group' => $this->generateGroupParameter($member),
+		];
+
+		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+			$this->setSubject($event, $ownEvent, $data);
+
+			return;
+		}
+
+		$this->setSubject($event, $othersEvent, $data);
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @throws FakeException
+	 */
+	public function parseSubjectCircleMemberJoin(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_circle_joined') {
+			return;
+		}
+
+		$this->parseMemberCircleEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You made {member} join {circle}'),
+			$this->l10n->t('{author} made {member} join {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @return void
+	 * @throws FakeException
+	 */
+	public function parseSubjectCircleMemberAdd(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_circle_added') {
+			return;
+		}
+
+		$this->parseMemberCircleEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You added team {member} as member to {circle}'),
+			$this->l10n->t('{author} added team {member} as member to {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @return void
+	 * @throws FakeException
+	 */
+	public function parseSubjectCircleMemberLeft(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_circle_left') {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You made {member} leave {circle}'),
+			$this->l10n->t('{author} made {member} leave {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @return void
+	 * @throws FakeException
+	 */
+	public function parseSubjectCircleMemberRemove(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_circle_removed') {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You removed {member} from {circle}'),
+			$this->l10n->t('{author} removed {member} from {circle}')
+		);
+
+		throw new FakeException();
+	}
+}
diff --git a/lib/Activity/Deprecated/ProviderSubjectMember.php b/lib/Activity/Deprecated/ProviderSubjectMember.php
new file mode 100644
index 000000000..a5ab9a96e
--- /dev/null
+++ b/lib/Activity/Deprecated/ProviderSubjectMember.php
@@ -0,0 +1,438 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Circles\Activity\Deprecated;
+
+use OCA\Circles\Exceptions\FakeException;
+use OCA\Circles\Model\Circle;
+use OCA\Circles\Model\Member;
+use OCP\Activity\IEvent;
+
+class ProviderSubjectMember extends ProviderParser {
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	public function parseSubjectMemberJoin(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_join') {
+			return;
+		}
+
+		$this->parseSubjectMemberJoinOnInvite($event, $circle, $member);
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member, $this->l10n->t('You joined {circle}'),
+			$this->l10n->t('{member} joined {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectMemberJoinOnInvite(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if (!$circle->isConfig(Circle::CFG_INVITE)) {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You accepted the invitation to join {circle}'),
+			$this->l10n->t('{member} accepted the invitation to join {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	public function parseSubjectMemberAdd(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_added') {
+			return;
+		}
+
+		$this->parseSubjectMemberAddNotLocalMember($event, $circle, $member);
+		$this->parseSubjectMemberAddClosedCircle($event, $circle, $member);
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You added {member} as member to {circle}'),
+			$this->l10n->t('You have been added as member to {circle} by {author}'),
+			$this->l10n->t('{member} has been added as member to {circle} by {author}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectMemberAddNotLocalMember(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($member->getUserType() === Member::TYPE_USER) {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You added {external} to {circle}'),
+			$this->l10n->t('{external} has been added to {circle} by {author}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectMemberAddClosedCircle(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if (!$circle->isConfig(Circle::CFG_REQUEST)) {
+			return;
+		}
+
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t("You accepted {member}'s request to join {circle}"),
+			$this->l10n->t('Your request to join {circle} has been accepted by {author}'),
+			$this->l10n->t("{member}'s request to join {circle} has been accepted by {author}")
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	public function parseSubjectMemberLeft(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_left') {
+			return;
+		}
+
+		$this->parseSubjectNonMemberLeftInvite($event, $circle, $member);
+		$this->parseSubjectNonMemberLeftRequest($event, $circle, $member);
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You left {circle}'),
+			$this->l10n->t('{member} left {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectNonMemberLeftInvite(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if (!$circle->isConfig(Circle::CFG_INVITE)
+			|| $member->getLevel() > Member::LEVEL_NONE) {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You declined the invitation to join {circle}'),
+			$this->l10n->t('{member} declined an invitation to join {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectNonMemberLeftRequest(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if (!$circle->isConfig(Circle::CFG_REQUEST)
+			|| $member->getLevel() > Member::LEVEL_NONE) {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You cancelled your request to join {circle}'),
+			$this->l10n->t('{member} cancelled a request to join {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	public function parseSubjectMemberRemove(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_remove') {
+			return;
+		}
+
+		$this->parseSubjectMemberRemoveNotLocalMember($event, $circle, $member);
+		$this->parseSubjectMemberRemoveNotYetMember($event, $circle, $member);
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You removed {member} from {circle}'),
+			$this->l10n->t('You have been removed from {circle} by {author}'),
+			$this->l10n->t('{member} has been removed from {circle} by {author}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectMemberRemoveNotLocalMember(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($member->getUserType() === Member::TYPE_USER) {
+			return;
+		}
+
+		$this->parseCircleMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You removed {external} from {circle}'),
+			$this->l10n->t('{external} has been removed from {circle} by {author}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	private function parseSubjectMemberRemoveNotYetMember(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if (!$circle->isConfig(Circle::CFG_INVITE)
+			|| $member->getLevel() > Member::LEVEL_NONE) {
+			return;
+		}
+
+		$this->parseSubjectMemberRemoveNotYetMemberRequesting($event, $circle, $member);
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t("You cancelled {member}'s invitation to join {circle}"),
+			$this->l10n->t('Your invitation to join {circle} has been cancelled by {author}'),
+			$this->l10n->t("{author} cancelled {member}'s invitation to join {circle}")
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @throws FakeException
+	 */
+	private function parseSubjectMemberRemoveNotYetMemberRequesting(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($member->getStatus() !== Member::STATUS_REQUEST) {
+			return;
+		}
+
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t("You dismissed {member}'s request to join {circle}"),
+			$this->l10n->t('Your request to join {circle} has been dismissed by {author}'),
+			$this->l10n->t("{member}'s request to join {circle} has been dismissed by {author}")
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @throws FakeException
+	 */
+	public function parseMemberInvited(IEvent $event, Circle $circle, Member $member): void {
+		if ($event->getSubject() !== 'member_invited') {
+			return;
+		}
+
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You invited {member} to join {circle}'),
+			$this->l10n->t('You have been invited to join {circle} by {author}'),
+			$this->l10n->t('{member} has been invited to join {circle} by {author}')
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @param int $level
+	 * @throws FakeException
+	 */
+	public function parseMemberLevel(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+		int $level,
+	): void {
+		if ($event->getSubject() !== 'member_level') {
+			return;
+		}
+
+		$levelString = $this->l10n->t(Member::$DEF_LEVEL[$level] ?? '');
+		$this->parseCircleMemberAdvancedEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You changed {member}\'s level in {circle} to %1$s', [$levelString]),
+			$this->l10n->t('{author} changed your level in {circle} to %1$s', [$levelString]),
+			$this->l10n->t('{author} changed {member}\'s level in {circle} to %1$s', [$levelString])
+		);
+
+		throw new FakeException();
+	}
+
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	public function parseMemberRequestInvitation(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_request_invitation') {
+			return;
+		}
+
+		$this->parseMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You sent a request to join {circle}'),
+			$this->l10n->t('{member} sent a request to join {circle}')
+		);
+
+		throw new FakeException();
+	}
+
+	/**
+	 * @param IEvent $event
+	 * @param Circle $circle
+	 * @param Member $member
+	 *
+	 * @throws FakeException
+	 */
+	public function parseMemberOwner(
+		IEvent $event,
+		Circle $circle,
+		Member $member,
+	): void {
+		if ($event->getSubject() !== 'member_owner') {
+			return;
+		}
+
+		$this->parseMemberEvent(
+			$event, $circle, $member,
+			$this->l10n->t('You are the new owner of {circle}'),
+			$this->l10n->t('{member} is the new owner of {circle}')
+		);
+		throw new FakeException();
+	}
+}
diff --git a/lib/Activity/Provider.php b/lib/Activity/Provider.php
index 2a1c5b032..1a796846c 100644
--- a/lib/Activity/Provider.php
+++ b/lib/Activity/Provider.php
@@ -11,8 +11,6 @@
 
 use OCA\Circles\AppInfo\Application;
 use OCA\Circles\Exceptions\FakeException;
-use OCA\Circles\Model\Circle;
-use OCA\Circles\Model\Member;
 use OCA\Circles\Tools\Exceptions\InvalidItemException;
 use OCA\Circles\Tools\Traits\TDeserialize;
 use OCP\Activity\Exceptions\UnknownActivityException;
@@ -30,6 +28,7 @@ public function __construct(
 		private ProviderSubjectCircle $parserCircle,
 		private ProviderSubjectMember $parserMember,
 		private ProviderSubjectCircleMember $parserCircleMember,
+		private Deprecated\Provider $deprecatedProvider,
 	) {
 	}
 
@@ -39,16 +38,17 @@ public function __construct(
 	public function parse($language, IEvent $event, ?IEvent $previousEvent = null): IEvent {
 		try {
 			$params = $event->getSubjectParameters();
-			$this->initActivityParser($event, $params);
+			$ver = $this->initActivityParser($event, $params);
 
-			/** @var Circle $circle */
-			$circle = $this->deserializeJson($params['circle'], Circle::class);
+			if ($ver === 1) {
+				return $this->deprecatedProvider->parse($language, $event, $previousEvent);
+			}
 
 			$this->setIcon($event);
-			$this->parseAsNonMember($event, $circle);
-			$this->parseAsMember($event, $circle, $params);
-			$this->parseAsModerator($event, $circle, $params);
-		} catch (FakeException|InvalidItemException $e) {
+			$this->parseAsNonMember($event, $params);
+			$this->parseAsMember($event, $params);
+			$this->parseAsModerator($event, $params);
+		} catch (FakeException|InvalidItemException) {
 			/** clean exit */
 		}
 
@@ -59,7 +59,7 @@ public function parse($language, IEvent $event, ?IEvent $previousEvent = null):
 	 * @param IEvent $event
 	 * @param array $params
 	 */
-	private function initActivityParser(IEvent $event, array $params): void {
+	private function initActivityParser(IEvent $event, array $params): int {
 		if ($event->getApp() !== Application::APP_ID) {
 			throw new UnknownActivityException();
 		}
@@ -67,6 +67,8 @@ private function initActivityParser(IEvent $event, array $params): void {
 		if (!key_exists('circle', $params)) {
 			throw new UnknownActivityException();
 		}
+
+		return $params['ver'] ?? 1;
 	}
 
 	/**
@@ -79,115 +81,98 @@ private function setIcon(IEvent $event): void {
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
 	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseAsNonMember(
 		IEvent $event,
-		Circle $circle,
+		array $params,
 	): void {
 		if ($event->getType() !== 'circles_as_non_member') {
 			return;
 		}
 
-		$this->parserCircle->parseSubjectCircleCreate($event, $circle);
+		$this->parserCircle->parseSubjectCircleCreate($event, $params);
 	}
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
 	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseAsMember(
 		IEvent $event,
-		Circle $circle,
 		array $params,
 	): void {
 		if ($event->getType() !== 'circles_as_member') {
 			return;
 		}
 
-		$this->parserCircle->parseSubjectCircleCreate($event, $circle);
-		$this->parserCircle->parseSubjectCircleDelete($event, $circle);
-		$this->parseMemberAsMember($event, $circle, $params);
-		$this->parseCircleMemberAsMember($event, $circle, $params);
+		$this->parserCircle->parseSubjectCircleCreate($event, $params);
+		$this->parserCircle->parseSubjectCircleDelete($event, $params);
+		$this->parseMemberAsMember($event, $params);
+		$this->parseCircleMemberAsMember($event, $params);
 	}
 
 	/**
-	 * @param Circle $circle
 	 * @param IEvent $event
 	 * @param array $params
 	 *
 	 * @throws FakeException
 	 * @throws InvalidItemException
 	 */
-	private function parseAsModerator(IEvent $event, Circle $circle, array $params): void {
+	private function parseAsModerator(IEvent $event, array $params): void {
 		if ($event->getType() !== 'circles_as_moderator') {
 			return;
 		}
 
-		$this->parseMemberAsModerator($event, $circle, $params);
+		$this->parseMemberAsModerator($event, $params);
 	}
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
 	 * @param array $params
 	 *
 	 * @throws FakeException
-	 * @throws InvalidItemException
 	 */
 	private function parseMemberAsMember(
 		IEvent $event,
-		Circle $circle,
 		array $params,
 	): void {
-		if (!key_exists('member', $params)) {
+		if (!array_key_exists('member', $params)) {
 			return;
 		}
 
-		/** @var Member $member */
-		$member = $this->deserializeJson($params['member'], Member::class);
-
-		$this->parserMember->parseSubjectMemberJoin($event, $circle, $member);
-		$this->parserMember->parseSubjectMemberAdd($event, $circle, $member);
-		$this->parserMember->parseSubjectMemberLeft($event, $circle, $member);
-		$this->parserMember->parseSubjectMemberRemove($event, $circle, $member);
+		$this->parserMember->parseSubjectMemberJoin($event, $params);
+		$this->parserMember->parseSubjectMemberAdd($event, $params);
+		$this->parserMember->parseSubjectMemberLeft($event, $params);
+		$this->parserMember->parseSubjectMemberRemove($event, $params);
 	}
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
 	 * @param array $params
 	 *
 	 * @throws FakeException
-	 * @throws InvalidItemException
 	 */
 	private function parseCircleMemberAsMember(
 		IEvent $event,
-		Circle $circle,
 		array $params,
 	): void {
-		if (!key_exists('member', $params)) {
+		if (!array_key_exists('member', $params)) {
 			return;
 		}
 
-		/** @var Member $member */
-		$member = $this->deserializeJson($params['member'], Member::class);
-
-		$this->parserCircleMember->parseSubjectCircleMemberJoin($event, $circle, $member);
-		$this->parserCircleMember->parseSubjectCircleMemberAdd($event, $circle, $member);
-		$this->parserCircleMember->parseSubjectCircleMemberLeft($event, $circle, $member);
-		$this->parserCircleMember->parseSubjectCircleMemberRemove($event, $circle, $member);
+		$this->parserCircleMember->parseSubjectCircleMemberJoin($event, $params);
+		$this->parserCircleMember->parseSubjectCircleMemberAdd($event, $params);
+		$this->parserCircleMember->parseSubjectCircleMemberLeft($event, $params);
+		$this->parserCircleMember->parseSubjectCircleMemberRemove($event, $params);
 	}
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
 	 * @param array $params
 	 *
 	 * @throws FakeException
@@ -195,19 +180,15 @@ private function parseCircleMemberAsMember(
 	 */
 	private function parseMemberAsModerator(
 		IEvent $event,
-		Circle $circle,
 		array $params,
 	): void {
-		if (!key_exists('member', $params)) {
+		if (!array_key_exists('member', $params)) {
 			return;
 		}
 
-		/** @var Member $member */
-		$member = $this->deserializeJson($params['member'], Member::class);
-
-		$this->parserMember->parseMemberInvited($event, $circle, $member);
-		$this->parserMember->parseMemberLevel($event, $circle, $member, $params['level'] ?? 0);
-		$this->parserMember->parseMemberRequestInvitation($event, $circle, $member);
-		$this->parserMember->parseMemberOwner($event, $circle, $member);
+		$this->parserMember->parseMemberInvited($event, $params);
+		$this->parserMember->parseMemberLevel($event, $params);
+		$this->parserMember->parseMemberRequestInvitation($event, $params);
+		$this->parserMember->parseMemberOwner($event, $params);
 	}
 }
diff --git a/lib/Activity/ProviderParser.php b/lib/Activity/ProviderParser.php
index 26cafa70e..1a86369bf 100644
--- a/lib/Activity/ProviderParser.php
+++ b/lib/Activity/ProviderParser.php
@@ -9,8 +9,6 @@
 
 namespace OCA\Circles\Activity;
 
-use OCA\Circles\IFederatedUser;
-use OCA\Circles\Model\Circle;
 use OCA\Circles\Model\Member;
 use OCP\Activity\IEvent;
 use OCP\Activity\IManager;
@@ -25,24 +23,18 @@ public function __construct(
 	) {
 	}
 
-	/**
-	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param string $ownEvent
-	 * @param string $othersEvent
-	 */
 	protected function parseCircleEvent(
 		IEvent $event,
-		Circle $circle,
+		array $params,
 		string $ownEvent,
 		string $othersEvent,
 	): void {
 		$data = [
-			'author' => $this->generateViewerParameter($circle),
-			'circle' => $this->generateCircleParameter($circle)
+			'author' => $this->generateUserParameter($params['initiator'] ?? []),
+			'circle' => $this->generateCircleParameter($params['circle'])
 		];
 
-		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+		if ($this->isViewerTheAuthor($params['initiator'] ?? [], $this->activityManager->getCurrentUserId())) {
 			$this->setSubject($event, $ownEvent, $data);
 
 			return;
@@ -113,25 +105,22 @@ protected function setParsedSubject(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 * @param string $ownEvent
 	 * @param string $othersEvent
 	 */
 	protected function parseMemberEvent(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 		string $ownEvent,
 		string $othersEvent,
 	): void {
 		$data = [
-			'circle' => $this->generateCircleParameter($circle),
-			'member' => $this->generateUserParameter($member)
+			'circle' => $this->generateCircleParameter($params['circle']),
+			'member' => $this->generateUserParameter($params['member'] ?? [])
 		];
 
-		if ($member->getUserId() === $this->activityManager->getCurrentUserId()
-		) {
+		if ($this->isViewerTheAuthor($params['member'] ?? [], $this->activityManager->getCurrentUserId())) {
 			$this->setSubject($event, $ownEvent, $data);
 
 			return;
@@ -142,27 +131,25 @@ protected function parseMemberEvent(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 * @param string $ownEvent
 	 * @param string $othersEvent
 	 */
 	protected function parseCircleMemberEvent(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 		string $ownEvent,
 		string $othersEvent,
 	): void {
 		$data = [
-			'author' => $this->generateViewerParameter($circle),
-			'circle' => $this->generateCircleParameter($circle),
-			'member' => $this->generateUserParameter($member),
-			'external' => $this->generateExternalMemberParameter($member),
-			'group' => $this->generateGroupParameter($member),
+			'author' => $this->generateUserParameter($params['initiator'] ?? []),
+			'circle' => $this->generateCircleParameter($params['circle']),
+			'member' => $this->generateUserParameter($params['member'] ?? []),
+			'external' => $this->generateExternalMemberParameter($params['member'] ?? []),
+			'group' => $this->generateGroupParameter($params['member'] ?? []),
 		];
 
-		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+		if ($this->isViewerTheAuthor($params['initiator'] ?? [], $this->activityManager->getCurrentUserId())) {
 			$this->setSubject($event, $ownEvent, $data);
 
 			return;
@@ -175,33 +162,31 @@ protected function parseCircleMemberEvent(
 	 * general function to generate Circle+Member advanced event.
 	 *
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 * @param string $ownEvent
 	 * @param string $targetEvent
 	 * @param string $othersEvent
 	 */
 	protected function parseCircleMemberAdvancedEvent(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 		string $ownEvent,
 		string $targetEvent,
 		string $othersEvent,
 	): void {
 		$data = [
-			'author' => $this->generateViewerParameter($circle),
-			'circle' => $this->generateCircleParameter($circle),
-			'member' => $this->generateUserParameter($member)
+			'author' => $this->generateUserParameter($params['initiator'] ?? []),
+			'circle' => $this->generateCircleParameter($params['circle']),
+			'member' => $this->generateUserParameter($params['member'] ?? [])
 		];
 
-		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+		if ($this->isViewerTheAuthor($params['initiator'] ?? [], $this->activityManager->getCurrentUserId())) {
 			$this->setSubject($event, $ownEvent, $data);
 
 			return;
 		}
 
-		if ($member->getUserId() === $this->activityManager->getCurrentUserId()) {
+		if ($this->isViewerTheAuthor($params['member'] ?? [], $this->activityManager->getCurrentUserId())) {
 			$this->setSubject($event, $targetEvent, $data);
 
 			return;
@@ -211,91 +196,74 @@ protected function parseCircleMemberAdvancedEvent(
 	}
 
 	/**
-	 * @param Circle $circle
+	 * @param array $params
 	 * @param string $userId
 	 *
 	 * @return bool
 	 */
-	protected function isViewerTheAuthor(Circle $circle, string $userId): bool {
-		if (!$circle->hasInitiator()) {
-			return false;
-		}
-
-		$initiator = $circle->getInitiator();
-
-		return ($initiator->getUserType() === Member::TYPE_USER
-			&& $initiator->getUserId() === $userId);
+	protected function isViewerTheAuthor(array $initiator, string $userId): bool {
+		return (($initiator['type'] ?? 0) === Member::TYPE_USER && ($initiator['userId'] ?? '') === $userId);
 	}
 
+
 	/**
-	 * @param Circle $circle
+	 * @param array $member
 	 *
 	 * @return array <string,string|integer>
 	 */
-	protected function generateViewerParameter(Circle $circle): array {
-		if (!$circle->hasInitiator()) {
-			return [];
+	protected function generateExternalMemberParameter(array $member): array {
+		$data = $this->generateUserParameter($member);
+		if (!empty($data)) {
+			$data['link'] = '';
 		}
 
-		return $this->generateUserParameter($circle->getInitiator());
-	}
-
-	/**
-	 * @param Member $member
-	 *
-	 * @return array <string,string|integer>
-	 */
-	protected function generateExternalMemberParameter(Member $member): array {
-		return [
-			'type' => 'email',
-			'id' => $member->getUserId(),
-			'link' => '',
-			'name' => $member->getDisplayName(),
-			'_parsed' => $member->getDisplayName()
-		];
+		return $data;
 	}
 
 	/**
-	 * @param Circle $circle
+	 * @param array $circle
 	 *
 	 * @return array<string,string|integer>
 	 */
-	protected function generateCircleParameter(Circle $circle): array {
+	protected function generateCircleParameter(array $circle): array {
 		return [
 			'type' => 'circle',
-			'id' => $circle->getSingleId(),
-			'name' => $circle->getName(),
-			'_parsed' => $circle->getName(),
-			'link' => $this->url->getAbsoluteURL($circle->getUrl()),
+			'id' => $circle['singleId'],
+			'name' => $circle['name'],
+			'_parsed' => $circle['name'],
+			'link' => $this->url->getAbsoluteURL($circle['url']),
 		];
 	}
 
 	/**
 	 * @return array <string,string|integer>
 	 */
-	protected function generateUserParameter(IFederatedUser $member): array {
-		$display = $member->getDisplayName();
-		if ($display === '') {
-			$display = $member->getUserId();
+	protected function generateUserParameter(array $member): array {
+		if (!array_key_exists('userId', $member)) {
+			return [];
 		}
 
 		return [
 			'type' => 'user',
-			'id' => $member->getUserId(),
-			'name' => $display,
-			'_parsed' => $display
+			'id' => $member['userId'],
+			'name' => $member['displayName'] ?? $member['userId'],
+			'_parsed' => $member['displayName'] ?? $member['userId'],
 		];
 	}
 
 	/**
 	 * @return array <string,string|integer>
 	 */
-	protected function generateGroupParameter(Member $group): array {
+	protected function generateGroupParameter(array $group): array {
+		if (!array_key_exists('userId', $group)) {
+			return [];
+		}
+
 		return [
 			'type' => 'user-group',
-			'id' => $group->getUserId(),
-			'name' => $group->getUserId(),
-			'_parsed' => $group->getUserId()
+			'id' => $group['userId'],
+			'name' => $group['userId'],
+			'_parsed' => $group['userId']
 		];
 	}
 }
diff --git a/lib/Activity/ProviderSubjectCircle.php b/lib/Activity/ProviderSubjectCircle.php
index dc955b568..f591929cd 100644
--- a/lib/Activity/ProviderSubjectCircle.php
+++ b/lib/Activity/ProviderSubjectCircle.php
@@ -10,23 +10,16 @@
 namespace OCA\Circles\Activity;
 
 use OCA\Circles\Exceptions\FakeException;
-use OCA\Circles\Model\Circle;
 use OCP\Activity\IEvent;
 
 class ProviderSubjectCircle extends ProviderParser {
-	/**
-	 * @param IEvent $event
-	 * @param Circle $circle
-	 *
-	 * @throws FakeException
-	 */
-	public function parseSubjectCircleCreate(IEvent $event, Circle $circle): void {
+	public function parseSubjectCircleCreate(IEvent $event, array $params): void {
 		if ($event->getSubject() !== 'circle_create') {
 			return;
 		}
 
 		$this->parseCircleEvent(
-			$event, $circle,
+			$event, $params,
 			$this->l10n->t('You created the team {circle}'),
 			$this->l10n->t('{author} created the team {circle}')
 		);
@@ -36,17 +29,17 @@ public function parseSubjectCircleCreate(IEvent $event, Circle $circle): void {
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
-	public function parseSubjectCircleDelete(IEvent $event, Circle $circle): void {
+	public function parseSubjectCircleDelete(IEvent $event, array $params): void {
 		if ($event->getSubject() !== 'circle_delete') {
 			return;
 		}
 
 		$this->parseCircleEvent(
-			$event, $circle,
+			$event, $params,
 			$this->l10n->t('You deleted {circle}'),
 			$this->l10n->t('{author} deleted {circle}')
 		);
diff --git a/lib/Activity/ProviderSubjectCircleMember.php b/lib/Activity/ProviderSubjectCircleMember.php
index 62c2962fc..50b464563 100644
--- a/lib/Activity/ProviderSubjectCircleMember.php
+++ b/lib/Activity/ProviderSubjectCircleMember.php
@@ -10,35 +10,30 @@
 namespace OCA\Circles\Activity;
 
 use OCA\Circles\Exceptions\FakeException;
-use OCA\Circles\Model\Circle;
-use OCA\Circles\Model\Member;
 use OCP\Activity\IEvent;
 
 class ProviderSubjectCircleMember extends ProviderParser {
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 * @param string $ownEvent
 	 * @param string $othersEvent
-	 * @return void
 	 */
 	protected function parseMemberCircleEvent(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 		string $ownEvent,
 		string $othersEvent,
 	): void {
 		$data = [
-			'author' => $this->generateViewerParameter($circle),
-			'circle' => $this->generateCircleParameter($circle),
-			'member' => $this->generateUserParameter($member),
-			'external' => $this->generateExternalMemberParameter($member),
-			'group' => $this->generateGroupParameter($member),
+			'author' => $this->generateUserParameter($params['initiator'] ?? []),
+			'circle' => $this->generateCircleParameter($params['circle']),
+			'member' => $this->generateUserParameter($params['member'] ?? []),
+			'external' => $this->generateExternalMemberParameter($params['member'] ?? []),
+			'group' => $this->generateGroupParameter($params['member'] ?? []),
 		];
 
-		if ($this->isViewerTheAuthor($circle, $this->activityManager->getCurrentUserId())) {
+		if ($this->isViewerTheAuthor($params['initiator'] ?? [], $this->activityManager->getCurrentUserId())) {
 			$this->setSubject($event, $ownEvent, $data);
 
 			return;
@@ -49,21 +44,20 @@ protected function parseMemberCircleEvent(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
+	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectCircleMemberJoin(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_circle_joined') {
 			return;
 		}
 
 		$this->parseMemberCircleEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You made {member} join {circle}'),
 			$this->l10n->t('{author} made {member} join {circle}')
 		);
@@ -73,22 +67,20 @@ public function parseSubjectCircleMemberJoin(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
-	 * @return void
+	 * @param array $params
+	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectCircleMemberAdd(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_circle_added') {
 			return;
 		}
 
 		$this->parseMemberCircleEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You added team {member} as member to {circle}'),
 			$this->l10n->t('{author} added team {member} as member to {circle}')
 		);
@@ -98,22 +90,20 @@ public function parseSubjectCircleMemberAdd(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
-	 * @return void
+	 * @param array $params
+	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectCircleMemberLeft(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_circle_left') {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You made {member} leave {circle}'),
 			$this->l10n->t('{author} made {member} leave {circle}')
 		);
@@ -123,22 +113,20 @@ public function parseSubjectCircleMemberLeft(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
-	 * @return void
+	 * @param array $params
+	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectCircleMemberRemove(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_circle_removed') {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You removed {member} from {circle}'),
 			$this->l10n->t('{author} removed {member} from {circle}')
 		);
diff --git a/lib/Activity/ProviderSubjectMember.php b/lib/Activity/ProviderSubjectMember.php
index cd1f74795..2118e611f 100644
--- a/lib/Activity/ProviderSubjectMember.php
+++ b/lib/Activity/ProviderSubjectMember.php
@@ -17,23 +17,21 @@
 class ProviderSubjectMember extends ProviderParser {
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectMemberJoin(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_join') {
 			return;
 		}
 
-		$this->parseSubjectMemberJoinOnInvite($event, $circle, $member);
+		$this->parseSubjectMemberJoinOnInvite($event, $params);
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member, $this->l10n->t('You joined {circle}'),
+			$event, $params, $this->l10n->t('You joined {circle}'),
 			$this->l10n->t('{member} joined {circle}')
 		);
 
@@ -42,22 +40,20 @@ public function parseSubjectMemberJoin(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectMemberJoinOnInvite(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if (!$circle->isConfig(Circle::CFG_INVITE)) {
+		if ((($params['circle']['config'] ?? 0) & Circle::CFG_INVITE) === 0) {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You accepted the invitation to join {circle}'),
 			$this->l10n->t('{member} accepted the invitation to join {circle}')
 		);
@@ -68,24 +64,22 @@ private function parseSubjectMemberJoinOnInvite(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectMemberAdd(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_added') {
 			return;
 		}
 
-		$this->parseSubjectMemberAddNotLocalMember($event, $circle, $member);
-		$this->parseSubjectMemberAddClosedCircle($event, $circle, $member);
+		$this->parseSubjectMemberAddNotLocalMember($event, $params);
+		$this->parseSubjectMemberAddClosedCircle($event, $params);
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You added {member} as member to {circle}'),
 			$this->l10n->t('You have been added as member to {circle} by {author}'),
 			$this->l10n->t('{member} has been added as member to {circle} by {author}')
@@ -96,22 +90,20 @@ public function parseSubjectMemberAdd(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectMemberAddNotLocalMember(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if ($member->getUserType() === Member::TYPE_USER) {
+		if (($params['member']['type'] ?? Member::TYPE_USER) === Member::TYPE_USER) {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You added {external} to {circle}'),
 			$this->l10n->t('{external} has been added to {circle} by {author}')
 		);
@@ -122,22 +114,20 @@ private function parseSubjectMemberAddNotLocalMember(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectMemberAddClosedCircle(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if (!$circle->isConfig(Circle::CFG_REQUEST)) {
+		if ((($params['circle']['config'] ?? 0) & Circle::CFG_REQUEST) === 0) {
 			return;
 		}
 
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t("You accepted {member}'s request to join {circle}"),
 			$this->l10n->t('Your request to join {circle} has been accepted by {author}'),
 			$this->l10n->t("{member}'s request to join {circle} has been accepted by {author}")
@@ -149,24 +139,22 @@ private function parseSubjectMemberAddClosedCircle(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectMemberLeft(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_left') {
 			return;
 		}
 
-		$this->parseSubjectNonMemberLeftInvite($event, $circle, $member);
-		$this->parseSubjectNonMemberLeftRequest($event, $circle, $member);
+		$this->parseSubjectNonMemberLeftInvite($event, $params);
+		$this->parseSubjectNonMemberLeftRequest($event, $params);
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You left {circle}'),
 			$this->l10n->t('{member} left {circle}')
 		);
@@ -177,23 +165,21 @@ public function parseSubjectMemberLeft(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectNonMemberLeftInvite(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if (!$circle->isConfig(Circle::CFG_INVITE)
-			|| $member->getLevel() > Member::LEVEL_NONE) {
+		if (((($params['circle']['config'] ?? 0) & Circle::CFG_INVITE) === 0)
+			|| (($params['member']['level'] ?? 1) > Member::LEVEL_NONE)) {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You declined the invitation to join {circle}'),
 			$this->l10n->t('{member} declined an invitation to join {circle}')
 		);
@@ -204,23 +190,21 @@ private function parseSubjectNonMemberLeftInvite(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectNonMemberLeftRequest(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if (!$circle->isConfig(Circle::CFG_REQUEST)
-			|| $member->getLevel() > Member::LEVEL_NONE) {
+		if (((($params['circle']['config'] ?? 0) & Circle::CFG_REQUEST) === 0)
+			|| (($params['member']['level'] ?? 1) > Member::LEVEL_NONE)) {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You cancelled your request to join {circle}'),
 			$this->l10n->t('{member} cancelled a request to join {circle}')
 		);
@@ -231,24 +215,22 @@ private function parseSubjectNonMemberLeftRequest(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	public function parseSubjectMemberRemove(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_remove') {
 			return;
 		}
 
-		$this->parseSubjectMemberRemoveNotLocalMember($event, $circle, $member);
-		$this->parseSubjectMemberRemoveNotYetMember($event, $circle, $member);
+		$this->parseSubjectMemberRemoveNotLocalMember($event, $params);
+		$this->parseSubjectMemberRemoveNotYetMember($event, $params);
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You removed {member} from {circle}'),
 			$this->l10n->t('You have been removed from {circle} by {author}'),
 			$this->l10n->t('{member} has been removed from {circle} by {author}')
@@ -259,22 +241,20 @@ public function parseSubjectMemberRemove(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectMemberRemoveNotLocalMember(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if ($member->getUserType() === Member::TYPE_USER) {
+		if (($params['member']['type'] ?? Member::TYPE_USER) === Member::TYPE_USER) {
 			return;
 		}
 
 		$this->parseCircleMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You removed {external} from {circle}'),
 			$this->l10n->t('{external} has been removed from {circle} by {author}')
 		);
@@ -285,24 +265,22 @@ private function parseSubjectMemberRemoveNotLocalMember(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	private function parseSubjectMemberRemoveNotYetMember(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if (!$circle->isConfig(Circle::CFG_INVITE)
-			|| $member->getLevel() > Member::LEVEL_NONE) {
+		if (((($params['circle']['config'] ?? 0) & Circle::CFG_INVITE) === 0)
+			|| (($params['member']['level'] ?? 1) > Member::LEVEL_NONE)) {
 			return;
 		}
 
-		$this->parseSubjectMemberRemoveNotYetMemberRequesting($event, $circle, $member);
+		$this->parseSubjectMemberRemoveNotYetMemberRequesting($event, $params);
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t("You cancelled {member}'s invitation to join {circle}"),
 			$this->l10n->t('Your invitation to join {circle} has been cancelled by {author}'),
 			$this->l10n->t("{author} cancelled {member}'s invitation to join {circle}")
@@ -313,21 +291,19 @@ private function parseSubjectMemberRemoveNotYetMember(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 * @throws FakeException
 	 */
 	private function parseSubjectMemberRemoveNotYetMemberRequesting(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
-		if ($member->getStatus() !== Member::STATUS_REQUEST) {
+		if (($params['member']['status'] ?? '') !== Member::STATUS_REQUEST) {
 			return;
 		}
 
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t("You dismissed {member}'s request to join {circle}"),
 			$this->l10n->t('Your request to join {circle} has been dismissed by {author}'),
 			$this->l10n->t("{member}'s request to join {circle} has been dismissed by {author}")
@@ -338,17 +314,17 @@ private function parseSubjectMemberRemoveNotYetMemberRequesting(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
+	 *
 	 * @throws FakeException
 	 */
-	public function parseMemberInvited(IEvent $event, Circle $circle, Member $member): void {
+	public function parseMemberInvited(IEvent $event, array $params): void {
 		if ($event->getSubject() !== 'member_invited') {
 			return;
 		}
 
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You invited {member} to join {circle}'),
 			$this->l10n->t('You have been invited to join {circle} by {author}'),
 			$this->l10n->t('{member} has been invited to join {circle} by {author}')
@@ -360,24 +336,22 @@ public function parseMemberInvited(IEvent $event, Circle $circle, Member $member
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
-	 * @param int $level
+	 * @param array $params
+	 *
 	 * @throws FakeException
 	 */
 	public function parseMemberLevel(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
-		int $level,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_level') {
 			return;
 		}
 
+		$level = $params['level'] ?? 0;
 		$levelString = $this->l10n->t(Member::$DEF_LEVEL[$level] ?? '');
 		$this->parseCircleMemberAdvancedEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You changed {member}\'s level in {circle} to %1$s', [$levelString]),
 			$this->l10n->t('{author} changed your level in {circle} to %1$s', [$levelString]),
 			$this->l10n->t('{author} changed {member}\'s level in {circle} to %1$s', [$levelString])
@@ -389,22 +363,20 @@ public function parseMemberLevel(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	public function parseMemberRequestInvitation(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_request_invitation') {
 			return;
 		}
 
 		$this->parseMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You sent a request to join {circle}'),
 			$this->l10n->t('{member} sent a request to join {circle}')
 		);
@@ -414,22 +386,20 @@ public function parseMemberRequestInvitation(
 
 	/**
 	 * @param IEvent $event
-	 * @param Circle $circle
-	 * @param Member $member
+	 * @param array $params
 	 *
 	 * @throws FakeException
 	 */
 	public function parseMemberOwner(
 		IEvent $event,
-		Circle $circle,
-		Member $member,
+		array $params,
 	): void {
 		if ($event->getSubject() !== 'member_owner') {
 			return;
 		}
 
 		$this->parseMemberEvent(
-			$event, $circle, $member,
+			$event, $params,
 			$this->l10n->t('You are the new owner of {circle}'),
 			$this->l10n->t('{member} is the new owner of {circle}')
 		);
diff --git a/lib/Service/ActivityService.php b/lib/Service/ActivityService.php
index 83d950ef3..c33a52eff 100644
--- a/lib/Service/ActivityService.php
+++ b/lib/Service/ActivityService.php
@@ -41,7 +41,14 @@ public function onCircleCreation(Circle $circle): void {
 		}
 
 		$event = $this->generateEvent('circles_as_non_member');
-		$event->setSubject('circle_create', ['circle' => json_encode($circle)]);
+		$event->setSubject(
+			'circle_create',
+			[
+				'ver' => 2,
+				'circle' => $this->shortenCircleData($circle),
+				'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+			]
+		);
 
 		$this->userManager->callForSeenUsers(
 			function ($user) use ($event) {
@@ -60,7 +67,14 @@ public function onCircleDestruction(Circle $circle): void {
 		}
 
 		$event = $this->generateEvent('circles_as_member');
-		$event->setSubject('circle_delete', ['circle' => json_encode($circle)]);
+		$event->setSubject(
+			'circle_delete',
+			[
+				'ver' => 2,
+				'circle' => $this->shortenCircleData($circle),
+				'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+			]
+		);
 		$this->publishEvent(
 			$event,
 			$this->memberRequest->getInheritedMembers($circle->getSingleId(), false, Member::LEVEL_MEMBER)
@@ -122,8 +136,10 @@ private function onMemberNewAccount(
 					CircleGenericEvent::JOINED => 'member_join'
 				},
 				[
-					'circle' => json_encode($circle),
-					'member' => json_encode($member)
+					'ver' => 2,
+					'circle' => $this->shortenCircleData($circle),
+					'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+					'member' => $this->shortenMemberData($member),
 				]
 			);
 		} catch (UnhandledMatchError $e) {
@@ -161,8 +177,10 @@ private function onMemberNewCircle(
 					CircleGenericEvent::JOINED => 'member_circle_joined'
 				},
 				[
-					'circle' => json_encode($circle),
-					'member' => json_encode($member)
+					'ver' => 2,
+					'circle' => $this->shortenCircleData($circle),
+					'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+					'member' => $this->shortenMemberData($member),
 				]
 			);
 		} catch (UnhandledMatchError $e) {
@@ -200,8 +218,10 @@ private function onMemberAlmost(
 					CircleGenericEvent::REQUESTED => 'member_request_invitation'
 				},
 				[
-					'circle' => json_encode($circle),
-					'member' => json_encode($member)
+					'ver' => 2,
+					'circle' => $this->shortenCircleData($circle),
+					'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+					'member' => $this->shortenMemberData($member),
 				]
 			);
 		} catch (UnhandledMatchError $e) {
@@ -244,7 +264,6 @@ public function onMemberRemove(Circle $circle, Member $member, int $eventType):
 		}
 	}
 
-
 	private function onMemberRemoveAccount(
 		Circle $circle,
 		Member $member,
@@ -259,8 +278,10 @@ private function onMemberRemoveAccount(
 					CircleGenericEvent::REMOVED => 'member_remove'
 				},
 				[
-					'circle' => json_encode($circle),
-					'member' => json_encode($member)
+					'ver' => 2,
+					'circle' => $this->shortenCircleData($circle),
+					'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+					'member' => $this->shortenMemberData($member),
 				]
 			);
 		} catch (UnhandledMatchError $e) {
@@ -293,8 +314,10 @@ private function onMemberRemoveCircle(
 					CircleGenericEvent::REMOVED => 'member_circle_removed'
 				},
 				[
-					'circle' => json_encode($circle),
-					'member' => json_encode($member)
+					'ver' => 2,
+					'circle' => $this->shortenCircleData($circle),
+					'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+					'member' => $this->shortenMemberData($member),
 				]
 			);
 		} catch (UnhandledMatchError $e) {
@@ -328,17 +351,23 @@ public function onMemberLevel(
 		$event = $this->generateEvent('circles_as_moderator');
 		$event->setSubject(
 			'member_level',
-			['circle' => json_encode($circle), 'member' => json_encode($member), 'level' => $level]
+			[
+				'ver' => 2,
+				'circle' => $this->shortenCircleData($circle),
+				'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+				'member' => $this->shortenMemberData($member),
+				'level' => $level
+			]
 		);
 
 		$this->publishEvent(
 			$event, array_merge(
 				[$member],
-				$this->memberRequest->getInheritedMembers($circle->getSingleId(), false, Member::LEVEL_MODERATOR))
+				$this->memberRequest->getInheritedMembers($circle->getSingleId(), false, Member::LEVEL_MODERATOR)
+			)
 		);
 	}
 
-
 	/**
 	 * @param Circle $circle
 	 * @param Member $member
@@ -347,7 +376,12 @@ public function onMemberOwner(Circle $circle, Member $member): void {
 		$event = $this->generateEvent('circles_as_moderator');
 		$event->setSubject(
 			'member_owner',
-			['circle' => json_encode($circle), 'member' => json_encode($member)]
+			[
+				'ver' => 2,
+				'circle' => $this->shortenCircleData($circle),
+				'initiator' => ($circle->hasInitiator() ? $this->shortenMemberData($circle->getInitiator()) : null),
+				'member' => $this->shortenMemberData($member),
+			]
 		);
 
 		$this->publishEvent(
@@ -356,11 +390,9 @@ public function onMemberOwner(Circle $circle, Member $member): void {
 		);
 	}
 
-
 	public function onShareNew(Circle $getCircle, FederatedEvent $federatedEvent): void {
 	}
 
-
 	/**
 	 * generateEvent()
 	 * Create an Activity Event with the basic settings for the app.
@@ -377,7 +409,6 @@ private function generateEvent(string $type): IEvent {
 		return $event;
 	}
 
-
 	/**
 	 * Publish the event to the users.
 	 * - if user is IUser, we get userId,
@@ -395,8 +426,8 @@ private function publishEvent(IEvent $event, array $users): void {
 				$userId = $user->getUID();
 			} elseif ($user instanceof IFederatedUser) {
 				$singleId = $user->getSingleId();
-				if ($user->getUserType() !== Member::TYPE_USER ||
-					in_array($singleId, $knownSingleIds)) {
+				if ($user->getUserType() !== Member::TYPE_USER
+					|| in_array($singleId, $knownSingleIds)) {
 					continue; // we ignore non-local account and already known single ids
 				}
 
@@ -410,4 +441,23 @@ private function publishEvent(IEvent $event, array $users): void {
 			$this->activityManager->publish($event);
 		}
 	}
+
+	private function shortenCircleData(Circle $circle): array {
+		return [
+			'singleId' => $circle->getSingleId(),
+			'name' => $circle->getName(),
+			'config' => $circle->getConfig(),
+			'url' => $circle->getUrl(),
+		];
+	}
+
+	private function shortenMemberData(Member $member): array {
+		return [
+			'userId' => $member->getUserId(),
+			'displayName' => $member->getDisplayName(),
+			'type' => $member->getUserType(),
+			'level' => $member->getLevel(),
+			'status' => $member->getStatus(),
+		];
+	}
 }