Golang

What is the difference between SQL and NoSQL?

Why did you move from [company] to [company]?

In [company], did you come to ready-made microservices and customize the functionality?

[name] asked: Do you use AI tools at work? If yes, which ones and for what purpose?

Is the garbage collector in Go blocking or non-blocking? Is its effect noticeable in production?

How is data stored in old Go maps after defining a bucket?

What locks exist in PostgreSQL?

What is EXPLAIN in PostgreSQL? How can it estimate without executing the query?

What happens to a slice in Go if its capacity is 8 and we try to add a ninth element?

How to share memory between goroutines? When is it better to use Atomic, and when Mutex/RWMutex/SyncMap?

Should OrderService be split into read and write components considering the load imbalance (25k reads vs 5k writes)?

Is 5000 write requests per second a lot? How do you plan to handle write-flow through all downstream services (Inventory, Payment, Delivery)?

What will change if you pass the initial capacity when creating a slice?

What is a partition in Kafka? Can a topic be without a partition?

What are the disadvantages of sharding?

What are the advantages of partitioning? For example, deleting old partitions.

If the EXPLAIN estimate significantly differs from EXPLAIN ANALYZE — what does it mean?

[name] asked: Where are you currently located and how do you feel about relocation?

Designing a fault-tolerant order processing system (payment gateway, logistics). Migration should be gradual without stopping the service. SCALE - Total users: 8 million - Daily active users (DAU): 3 million - Monthly active users (MAU): 12 million - Peak load: 25k reads / 5k writes per second - New data volume: 10 TB per year - Peak parallelism: 120k simultaneous requests - Annual user growth: 30% - Target p99 latency: <150 ms for reads, <400 ms for writes - Target availability: 99.95%. Your task is to develop an architectural solution that...

What sharding strategies do you know to make the solution less painful?