Lokal App | Tech Lead | Sept 2026 | Assumed Reject (Ghosted)
- Experience
- 8 years
- Posted
- 5 Oct 2026
Summary
I interviewed for a Tech Lead position at Lokal App; the first round focused on LLD and project discussion, and although the interview went well, I was later ghosted.
How it went
Company: Lokal App Current Org: Small Startup College: Tier-1 YOE: 8+ Current Comp: 60L Base + 10% Bonus + ESOPs
Round 1 - LLD & Project Discussion The interview started with a deep dive into past projects, followed by the main LLD question.
LLD Question: Design a Slack-like Notification System. Deliver real-time notifications to users based on messages and interactions across different conversation types. The system needs to intelligently decide when to notify a user based on message type, conversation type, user preferences, mentions, and thread participation.
Functional Requirements:
-
Conversation Types:
- Direct Messages (DMs) → 1:1 communication.
- Group Chats → Multiple users.
- Channels → Large groups (public/private, subscription-based).
-
Message Types:
- Each message belongs to a conversation and can optionally be part of a thread (
threadId). - Supported types: Text Messages, Multimedia Messages (images, videos, files), and Reactions.
- Each message belongs to a conversation and can optionally be part of a thread (
-
Notification Rules:
- Users should receive notifications for DMs, messages in groups they are a part of, messages in channels they subscribe to, and messages where they are @mentioned.
-
Thread-based Notifications:
- Notify users for thread activity if they have previously participated in the thread, explicitly followed/subscribed to the thread, or are @mentioned in a thread message.
- Thread notifications must also respect the parent conversation context (e.g., if the parent channel is muted).
-
Reaction Rules:
- Reactions must NOT trigger notifications. This applies universally across DMs, Groups, Channels, and Threads.
-
Mute & Notification Preferences:
- Conversation-level preferences: Notify All Messages, Notify Only Mentions, or Mute All Messages.
- Thread-level preferences (Bonus): Follow thread (always notify) or Mute thread (never notify).
Verdict: The round went well, and the interviewer was satisfied with the design. However, no further response was received. Assumed reject/ghosted.
Questions asked (1)
- 01
Design a Slack-like Notification System
System Design
Functional Requirements:
Conversation Types:
- Direct Messages (DMs) – 1:1 communication.
- Group Chats – Multiple users.
- Channels – Large groups (public/private, subscription‑based).
Message Types:
- Each message belongs to a conversation and can optionally be part of a thread (
threadId). - Supported types: Text Messages, Multimedia Messages (images, videos, files), and Reactions.
Notification Rules:
- Users receive notifications for DMs, messages in groups they belong to, messages in channels they subscribe to, and messages where they are @mentioned.
Thread‑based Notifications:
- Notify users for thread activity if they have previously participated, explicitly followed/subscribed to the thread, or are @mentioned in a thread message.
- Thread notifications respect the parent conversation context (e.g., muted channel).
Reaction Rules:
- Reactions must NOT trigger notifications across all conversation types.
Mute & Notification Preferences:
- Conversation‑level preferences: Notify All, Notify Only Mentions, Mute All.
- Thread‑level preferences (optional): Follow thread (always notify) or Mute thread (never notify).