🚨 Пытаюсь пройти РЕАЛЬНЫЙ собес на Senior Python Engineer / Финтех платформа с DSL / Опять фиаско?

*** 💡Awesome Python community on Telegram: https://t.me/pymentor 📡 Sign up for a mock interview: https://t.ly/lXoVH ✒️ Interviews, interviews, podcasts: https://www.youtube.com/@pymentor_by/... ✉️ Contact the channel's author - [email protected] *** Time codes: -- Introduction and format 0:00 — Welcome and meeting format: "IT smoking room" and dialogue. 0:54 — Interview outline: Theory and code review. -- Part 1: Technical theory (Python) 1:15 — What are caroutines in Python? Cooperative multitasking. 1:40 — How the Event Loop and the caroutine switching mechanism (`await`) work. 2:43 — Is it possible to deterministically control the execution order of caroutines? 3:30 — Data Synchronization: Locks vs. Queues. 4:06 — Data Isolation in Asynchronous Code: Deepcopy, Immutability, and the Actor Model. 6:10 — Using ContextVars for Context Isolation. 6:20 — Interfaces in Python: Philosophy and Declaration Methods. 7:52 — The Difference Between Abstract Classes (ABCs) and Protocols (typing.Protocol). 8:36 — Runtime Checkable Protocols and the Difference in Polymorphism. -- Part 2: Code Review (Practical) 9:00 — Moving to the Practical Part: Problem Overview. 10:06 — Problem Statement: Analysis of the Notification Class Hierarchy. 11:58 — Critique of the current implementation: Violation of SOLID and GRASP principles. 12:20 — Philosophical remark: When refactoring is justified for business. 13:20 — Analysis of violations: SRP (Single Responsibility) and Interface Segregation. 14:41 — Refactoring: Replacing inheritance with composition and aggregation. 16:32 — Practical implementation of interfaces via Protocols. 18:40 — The problem of a "bloated" inheritance tree and its solution. 20:25 — Implementing send logic via association. 26:25 — Moving serialization logic from business entities to custom dumpers. -- Part 3: Tools and AI 30:57 — Using AI (Copilot) in work: Writing tests and closing an issue. 32:17 — Experience with MCP (Model Context Protocol) and assistants. Platform and product overview 33:09 — Candidate question: "What kind of projects do you represent and what are their pain points?" 33:26 — Architecture: Platform core in Python (FastAPI) + React. 34:59 — Task specifics: Heavyweight applications, CPU-intensive calculations, and complex workflows. 36:04 — Positioning: Hybrid of an ERP system and a "combine" for financial instruments. 36:35 — Target user: How the platform helps quant engineers (Pricing code) deliver mathematics to businesses. Tech stack and migration 37:53 — DSL (Domain Specific Language) or framework? Declarative description of business objects. 39:31 — Global Goal: Migrating a huge system from .NET/C++ to the new Python platform. 40:36 — Why Python + React? Discussion of performance and possible Rust (Polars) implementation. 42:33 — Candidate's Lifehack: Using PyPy and JIT compilation to speed up Python by tens of times. 43:07 — Why did you leave the Microsoft ecosystem? A paradigm shift in the banking sector and the impact of AI. -- Architecture and Current State (POC) 45:16 — Current state of the platform and its role in calculating complex metrics (CVA, XVA). 46:35 — Infrastructure: Open-source plans, Docker/Kubernetes deployment, Redis for caching, and RabbitMQ for events. 47:41 — Workflow Engine: FastAPI + Celery and plans for migrating to Temporal. 48:53 — Tech Debt Strategy: "If it's not broken, don't touch it," focus on priority business goals. -- Team and Position 49:30 — Team Composition: Python Developers (5-6), QA Automation (Playwright), and Frontend (4-5). 51:16 — Who are we looking for? A "strong business manager," a Senior/Staff Engineer with a strong Vision. 51:52 — Role Responsibilities: Mentoring, architectural oversight, and combating code entropy (Code Ownership). 53:30 — Conclusion of the Interview. *** #python #interview #interview