Scale Engineer

Engineer 2

Software EngineerL4Medium to Hard

Instacart's Software Engineer (L4) interview process is designed to assess a candidate's technical proficiency, problem-solving abilities, and cultural fit within the company. The process typically involves multiple rounds, including technical interviews focusing on data structures, algorithms, and system design, as well as behavioral interviews to gauge collaboration and communication skills.

Rounds·3

Timeline·~14d

Experience·3 - 7 yrs

Comp band·US$120000 - US$160000

Interview time·150 min

Evaluation

What they measure.

  • Problem-solving skills
  • Algorithmic thinking
  • Data structure knowledge
  • System design capabilities
  • Coding proficiency
  • Communication skills
  • Teamwork and collaboration
  • Adaptability and learning agility

Preparation

How to prepare.

Tips

  1. Review fundamental data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming, graph traversal).
  2. Practice coding problems on platforms like LeetCode, HackerRank, or Coderbyte, focusing on medium to hard difficulty.
  3. Study system design principles, including scalability, availability, reliability, and common architectural patterns (microservices, load balancing, caching, databases).
  4. Prepare for behavioral questions by reflecting on your past experiences using the STAR method (Situation, Task, Action, Result).
  5. Understand Instacart's business model, products, and challenges to tailor your answers and demonstrate interest.
  6. Research common interview questions for Software Engineer roles at Instacart and similar tech companies.

Study plan

Fig · Study plan — 04 phases

01 / 04
01

Phase 01 of 04

Data Structures and Algorithms

Weeks 1-2: Data Structures & Algorithms fundamentals. Solve 2-3 problems daily.

Weeks 1-2: Focus on core data structures and algorithms. Cover arrays, linked lists, stacks, queues, trees (binary search trees, AVL trees, heaps), graphs, and hash tables. Practice algorithms like sorting (quicksort, mergesort), searching (binary search), recursion, dynamic programming, and graph traversal (BFS, DFS). Aim to solve at least 2-3 problems per day.

Questions

Commonly asked.

  • Given a list of grocery items and their prices, design a system to calculate the total cost of a shopping cart, considering discounts and taxes.
  • How would you design a recommendation engine for Instacart's customers?
  • Explain the difference between concurrency and parallelism and provide examples.
  • Describe a situation where you had to mentor a junior engineer. What was your approach?
  • Write a function to find the k-th largest element in an unsorted array.
  • How would you design a distributed cache for Instacart's product catalog?
  • Tell me about a time you disagreed with a technical decision. What did you do?
  • What are the trade-offs of using microservices versus a monolithic architecture?
  • Implement a function to validate if a binary tree is a Binary Search Tree.
  • How would you handle scaling issues if Instacart experienced a sudden surge in user traffic?

Locations

Regional differences.

Fig · Regions — 02 locations

01 / 02

Location

North America

Interview focus

Candidates in North America are often evaluated on their ability to scale systems and handle large datasets, given the market size.Emphasis on practical application of distributed systems concepts and cloud technologies (AWS, GCP).Behavioral questions may lean towards collaboration in a fast-paced, growth-oriented environment.

Common questions

  • How would you design a system to handle real-time grocery order updates for shoppers and customers?
  • Discuss a time you had to deal with a difficult stakeholder. How did you manage the situation?
  • Explain the trade-offs between using a relational database versus a NoSQL database for our product catalog.

Tips

  • Familiarize yourself with common distributed system patterns and their applications at scale.
  • Be prepared to discuss your experience with cloud platforms and microservices architecture.
  • Practice articulating your thought process clearly and concisely, especially when discussing trade-offs.

Rounds

Round-by-round.

Expand a step for evaluation criteria, sample questions, and prep notes.

DSA

Coding questions at Instacart.

Frequently reported on Instacart loops

View all at Instacart

Other guides

More at Instacart.