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System design patterns

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

3 matches

Domain Driven Design Aggregate Root Example in Python

Model an Order as an aggregate root with invariants enforced through methods, demonstrating DDD principles in Python.

from __future__ import annotations
from dataclasses import dataclass
from typing import List, Optional
from uuid import uuid4


class Money:
    def __init__(self, amount: float, currency: str = "USD"):
        self.amount = amount
        self.currency = currency

    def __add__(self, other: Money) -> Money:
       …

12 0 Open

System design patterns medium

How to Build a Pipe and Filter Text Processing Chain in Python

A functional pipe-and-filter chain that transforms text through uppercase, whitespace normalization, number removal, stopword filtering, and file export.

pipeline text-processing functional

Python

import re
import sys


def pipe_filter_chain(stream):
    def uppercase(text):
        return text.upper()

    def strip_whitespace(text):
        return " ".join(text.split())

    def remove_numbers(text):
        return re.sub(r"\d+", "", text)

    def remove_stopwords(text, stopwords={"the", "and", "of", "in"}):…

16 0 Open

System design patterns easy

Idempotent Consumer: Store Processed IDs in Python

Implement an idempotent consumer that persists processed message IDs to a JSON file, skipping duplicates on restart.

idempotency duplicate-detection state-persistence

Python

import json
from pathlib import Path


class IdempotentStore:
    def __init__(self, storage_path: str = "processed_ids.json"):
        self.storage_path = Path(storage_path)
        self.processed_ids = self._load()

    def _load(self) -> set:
        if self.storage_path.exists():
            with self.storage_path…

15 0 Open

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