Allen Digital Interview Experience | SDE-2 | Cleared 3 Rounds & Ghosted
Summary
I cleared three interview rounds—Machine Coding, DS/Problem Solving, and System Design—at Allen Digital for an SDE‑2 position and received a hire decision.
Full Experience
Round 1: Machine Coding (Verdict: Strong Hire)
Focus: Object-oriented design, functional working code, extensibility, and SOLID principles under time constraints.
Topics: Rate Limiter Outcome: Cleared with Strong Hire.
Round 2: DS / Problem Solving (Verdict: Strong Hire)
Focus: Core data structures, algorithmic complexity, and edge-case handling.
Topics: Q1. word ladder; Q2. Rotten oranges Outcome: Cleared with Strong Hire.
Round 3: System Design — 70% LLD / 30% HLD (Verdict: Hire)
Focus: Heavy focus on Low-Level Design (class diagrams, design patterns, DB schema) paired with high-level architecture concepts (caching, scalability, API design). Outcome: Cleared with Hire.
Interview Questions (3)
Rate Limiter Design
Design a rate limiter component using object‑oriented principles. The solution should be functional, extensible, and adhere to SOLID principles while handling concurrency and performance constraints.
Word Ladder
Given a begin word, an end word, and a dictionary of allowed words, find the length of the shortest transformation sequence from begin word to end word such that only one letter can be changed at a time and each intermediate word must exist in the dictionary. Return 0 if no such sequence exists.
Rotting Oranges
Given a grid where each cell can be empty (0), contain a fresh orange (1), or contain a rotten orange (2), determine the minimum number of minutes that must elapse until no fresh orange remains. Each minute, any fresh orange adjacent (4‑directionally) to a rotten orange becomes rotten. Return -1 if it is impossible to rot all oranges.