Describe the main principles and practices of development adopted in your last company.

In my practice, working with high load systems, I usually perform the following steps:

1. Monitoring and metrics analysis — study CPU, memory, disk, and network activity indicators to identify bottlenecks.
2. Code profiling — identify "heavy" parts that consume a lot of resources.
3. Query and algorithm optimization — rewrite slow queries, improve algorithms, reduce operations.
4. Caching — implement caching of frequently requested data to reduce database load.
5. Scaling — add horizontal or vertical scaling if necessary.
6. Asynchronous and queues — move heavy operations to background tasks to avoid blocking main threads.

For example, in one project, during a sharp user growth, I implemented Redis cache for frequently requested data and rewrote several SQL queries with indexes, which reduced response time and database load.