# Grokking Modern API Design Interview

## The API Design Interview

### Introduction: The API Design Interview

### What Is an API?

### How API Design Shows Up in Interviews

### What Interviewers Actually Grade

### A Framework for API Design Answers

### Requirements Gathering for an API

### The API as a Product

### Capstone: Design a URL Shortener API

### Chapter Assessment

## Designing a REST API

### What Are REST APIs?

### Introduction: Resource Modeling and REST Core

### Resources, Not Actions

### HTTP Methods and Their Semantics

### URL Design

### Request and Response Shapes

### Field Types That Break Contracts

### Status Codes and Error Design

### Pagination from the Consumer's View

### Filtering, Sorting, and Search

### When REST Doesn't Fit

### Bulk and Batch Operations

### Capstone: Design the Twitter API

### Chapter Assessment

## When REST Is Not Enough

### Introduction: Beyond REST

### gRPC Contract Design

### GraphQL Schema Design

### REST vs gRPC vs GraphQL

### Real Time Delivery: WebSockets, SSE, and Long Polling

### Webhooks: Designing the API That Calls Back

### Async APIs for Long Running Work

### Large Uploads and Downloads

### Capstone: Design a Live Notification API

### Chapter Assessment

## The Hard Parts: Failures, Security, and Change

### Introduction: The Hard Parts

### Idempotency Keys

### Rate Limiting in the Contract

### Authentication and Authorization for APIs

### Designing for Many Tenants

### Versioning and Backward Compatibility

### Concurrency and Conditional Requests

### Read Your Writes

### Caching in the Contract

### The Reliability Contract

### Capstone: Design a Payment API

### Chapter Assessment

## APIs for AI Products

### Introduction: APIs in the AI Era

### Streaming LLM APIs

### Designing APIs for AI Agents

### Usage Metering and Billing APIs

### Rate Limiting Expensive Compute

### Capstone: Design an LLM Inference API

### Chapter Assessment

## More Interview Questions

### Introduction: More Interview Questions

### Interview Question: Design a Chat API

### Interview Question: Design a Booking API

### Interview Question: Design a Feature Flag API

### Interview Question: Design a Checkout API

### Interview Question: Design a Calendar API

### Interview Question: Design a Collaborative Document API

### Chapter Assessment

## The Product Architecture Round

### Introduction: The Product Architecture Round

### From Feature to Data Model

### Designing for One Screen

### Offline, Sync, and Conflict

### Interview Question: Design the API Behind a News Feed Screen

### Interview Question: Design the API Behind a Messaging App

### Chapter Assessment

## Full Answers and Quick Review

### Introduction: Interview Questions and Rapid Review

### The 10 Minute API Answer

### Interview Question: Design a Ride Sharing API

### Interview Question: Design a File Storage API

### Interview Question: Critique This API

### Rapid Fire Questions

### Red Flags and Decision Cheat Sheets

### Chapter Assessment

## Conclusion: What You Now Know, and Where to Go Next

# Chapter Assessment

This checks the whole of Chapter 7: what the product architecture round adds, turning a feature into a data model, designing for one screen, offline sync and conflict, and the two worked answers for a news feed screen and a messaging app.

The pool holds 35 questions and each attempt asks 15, so repeat attempts will not be identical. The round adds two visible outputs but changes none of the six steps, so several wrong options here are storage designs offered where a product model was asked for. Read the explanation on every option.