What I Learned From 8 Backend Interviews: Real Stories & Technical Insights

Background: The author graduated in 2015 from a 985 university, spent time on entrepreneurship, and began a corporate job search in late 2016 with only one year of professional experience.

1. Afanti (阿凡题)

First interview at a K12 online‑education company in Wukou.

First round

Written test covering Python basics such as mutable vs immutable objects, garbage collection, simple coding tasks, and a data‑modeling question.

Second round

Self‑introduction, project‑related questions, simple system‑design discussion, and deeper review of the written‑test topics.

Third round

CTO asked broad questions from server deployment to Nginx details; the most memorable question was: “Explain in detail what happens from the moment a browser sends a request until the response returns.”

Answer summary:

1. Network model : client and server communicate via HTTP (application layer) over TCP (transport layer); HTTPS adds TLS/SSL. Below TCP are routing protocols (e.g., OSPF), ARP/RARP for IP‑MAC resolution, and the physical layer (IEEE 802.x).

When a browser sends a request, the data is packetized, the data‑link layer resolves IP‑MAC, the network layer performs routing, DNS resolves the host to an IP, and TCP performs the three‑way handshake before data transmission.

2. Application layer : HTTP is stateless; discuss GET/POST differences and RESTful design. Server models (epoll, select) are mentioned. A typical flow: Nginx receives the request, validates it, serves static resources directly, and forwards dynamic requests to uWSGI. uWSGI passes the WSGI environ to Django, which runs middleware, routes to the appropriate view, executes business logic, constructs the response, and returns it through uWSGI and Nginx back to the browser.

2. XueTang Online (学堂在线)

Three rounds: first with a backend engineer focusing on resume, Python basics, and system design; second with a department manager discussing system design; third HR round covering salary expectations and plans.

3. Guokr (果壳)

Interview required a detailed personal registration form. Written test included database queries and a classic O(1) stack problem that supports push, pop, and returns max/min values. Emphasized the importance of understanding database fundamentals such as indexes and storage engines.

4. Veeva

Phone interview followed by a homework task to implement a leap‑year check. Subsequent rounds covered Python/Django basics, algorithm questions, and a short‑URL generation design problem with collision avoidance.

5. Zhihu

Multiple rounds: first covered project experience and basic Python/algorithm questions; second focused on system design (e.g., WeChat red‑packet architecture); third was an HR discussion about career goals.

6. Chunyu Doctor

Rounds included practical coding tasks, a chat‑tool system‑design question, and a repeat of the browser‑request explanation from the Afanti CTO.

7. 360

Interview emphasized Linux fundamentals; the candidate lacked deep Linux knowledge, leading to a negative impression.

8. Toutiao

Five‑round process: first round involved coding (Fibonacci function) and discussion of Redis usage and hash‑table issues; second round added cache‑miss handling and a linked‑list reversal problem; third round covered system‑design topics such as multi‑device login and QR‑code login; fourth round was a casual HR discussion over a meal; fifth round finalized the offer.

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    return b

def reverse(node):
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    return p

Conclusion

The author accepted Toutiao’s offer and advises job seekers to seize campus recruitment opportunities, build personal projects, and study resources such as “剑指 Offer”.