Web backend development on DjangoRestFramework for several projects.

Summary:
* Design review, task estimation, and project setup.
* API design for new features.
* Extending legacy code with new features.
* Designing application in early stages with boilerplate for future extensions.

Projects:
* Large project selling online courses and managing physical exams. My contribution involved tweaking the payments module to support upcoming features and implementing API for a new login option.
* Setting up codebase and design, including DB, for new online service. Includes *almost* initial Django project setup, participation in GitHub Actions setup, code linters config, negotiating API with FE and product owner.
* Starting a new project in an outdoor advertisement. Participating in team task estimations, and designing API for sign-in, invitations, and other features; starting DJango project with linters integration, pre-commit hooks, DB design; implementing key features.

Design and implementation of automated tests using pytest and asyncio. The unusual bit in this is that we test Cloud communicating with many clients over different network protocols.

Stack I worked with here: pytest, asyncio, aiohttp, GRPC, HTS (proprietary protocol over TCP), allure, Jenkins, Docker & Docker compose.

* Design, development, and optimization of automated tests covering important
b2b and b2c solutions in an environment of complex custom protocols. Tests
involve working with DB, network communication, and multiple actors (to
emulate entities that communicate with the server). Automated tests cover
cases that would take enormous time if executed manually, and some of them
are hard to be reproduced manually (without scripting).
* Developed a system for accumulating definitions from 2 company protocols
into a single database, allowing for more straightforward data conversion from
one format to another.

See detailed description about the project I participated on while working at Ajax Systems in "Projects/Portfolio" section: Cloud test automation

* Design, development, and deployment of web backends and web scrapers. The flow of a typical project includes requirements negotiation, system design, software development, deployment, and maintenance.

* For example, I had a project with RabbitMQ as a message bus between async microservices written in Python 3. Workers save relational and more persistent data into PostgreSQL, while job artifacts are transferred to MongoDB to be extracted by another service. Asynchronous Sanic powers the backend. Microservices are containerized and scaled by Docker Compose. One of the challenges was to optimize jobs parallelization and SQL queries to meet the performance criteria.

* Another example: web scraper involving JS runtime with a need for web admin UI. Scrapy Splash service, deployed on VPS, provides JavaScript runtime, in which Lua scripts control functions. ScrapnigHub executes scrapers, but Celery workers control their scheduling to save money and unify control over the project. Django Admin web UI administrated Celery tasks and served as a view for results of scraper's work.

* Most projects required server management and software deployment, which I solved using Docker/Docker Compose/Docker Swarm (for the latter, I have a pretty solid boilerplate which allows for a cluster of servers cohosting multiple projects with management and monitoring through a browser). I mainly used Hetzner Cloud for hosting but have experience deploying onto Heroku/Dokku.