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System design patterns

Sharding, load balancing, CAP tradeoffs, and scaling patterns — interview and production ready.

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System design patterns easy

How to Implement a Simple Event Bus in Python

Create a publish-subscribe event bus using dataclasses and defaultdict to decouple event producers from consumers.

event-bus publish-subscribe design-patterns
Python 
from collections import defaultdict
from dataclasses import dataclass, field
from typing import Callable, Dict, List, Set


@dataclass
class EventBus:
    _subscribers: Dict[str, List[Callable]] = field(
        default_factory=lambda: defaultdict(list)
    )

    def subscribe(self, event_type: str, handler: Callable…
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