Project Pure

Improve simplicity and efficiency of the Scrollback codebase. Make it better suited for scaling up HeyNeighbor and other similar apps.

Key changes and business benefits

Architectural improvements

Including:

• Refactoring of modules in line with single responsibility
• Client-server communication using setstate and statechange
• Distributed architecture using Postgres listen/notify
• Common cache implementation for both client and server

Benefits:

• Real and perceived performance
• Scalability
• Faster development of other features
• Faster on-boarding of new developers

Item base class

Base class for texts, threads, rooms, topics and privchats.

type: (text/thread/room/topic/privchat)
parentId: { parentType: <id> or [<ids>] }
count: { countType: <number> }

This is a dependency for the changes below.

User-item relations

user:     (<userId>/<userIdentity>)
role:     (banned/none/visitor/mentioned/follower/moderator/owner)
status:   (writing/reading/online/reachable/offline)
intent:   (downvote/mute/upvote)
interest:   <number between 0 and 100>
reputation: <number between 0 and 100>

Enables the following features:

• “Heart” text or thread
• Flag a text or thread as offensive
• Mute thread
• Ban user from thread
• “Someone is typing”
• Invite non-users
• More relevant notifications

Item parents

• Organizes texts in threads or privchats, threads in rooms and topics
• Organizes rooms and topics in hierarchies (Apartment > Locality > City)

Item counts

Allows display of:

• Thread, follower and online counts in room/topic listings
• Number of hearts on a text or thread

Relation scores

• Interest and reputation scores to improve notification relevance

User counts

• Track private messages without replies
• Gamification: show total “hearts” received on profile
• Experience points on profile

User privileges

• App-level bans (permanent and time-bound)
• Cap on number of rooms user is allowed to follow
• Custom cap on private messages w/o replies

Query pagination with custom sort order

• Improves server scalability through partial retrieval of relations and notifications
• Sort threads by “liveness” score, f(startTime, updateTime, upvotes)
• Sort text search results by f(recency, relevance)

Separate unread from notifications

• Performance improvements

Item/user tombstones

• User/Room delete/rename