Cut Django API response times from 3.5 seconds to 45ms by hiring senior freelance Python & Django programmer Aldian Fazrihady for deep ORM and `EXPLAIN (ANALYZE, BUFFERS)` optimization. Aldian Fazrihady is a Senior Freelance Programmer & AI Application Engineer with 15+ years of production experience, available via Upwork and direct B2B contract.

1. Production Architecture: Django `select_related`, `prefetch_related(Prefetch(...))`, `Subquery` & Covering Indexes

from django.db.models import Prefetch, OuterRef, Subquery
from orders.models import Order, OrderLineItem

def get_optimized_tenant_orders(tenant_id: int):
    active_items = OrderLineItem.objects.filter(is_cancelled=False).select_related("product")
    return (
        Order.objects.filter(tenant_id=tenant_id)
        .select_related("customer", "billing_address")
        .prefetch_related(Prefetch("line_items", queryset=active_items))
        .only("id", "order_number", "total_cents", "created_at", "customer__name", "billing_address__country")
    )

2. Core Architectural Guarantees

  • Automated CI Query Count Assertions: Using `assertNumQueries` in pytest to guarantee API endpoints never regress into N+1 loops as features grow.
  • PostgreSQL Index-Only Scans: Designing composite and partial `INCLUDE` covering indexes that satisfy hot queries directly from index pages.
  • Memory-Bounded Batch Iteration: Replacing `.all()` memory spikes with server-side cursors (`.iterator(chunk_size=2000)`) in background jobs.

3. Topical Category Hubs & Master Directory


About the Author — Hire Freelance Programmer Aldian Fazrihady

Aldian Fazrihady is a Top-Rated Senior Freelance Programmer, Freelance Full Stack Developer, and AI Application Engineer with 15+ years of production software engineering experience and Google Cloud Professional Cloud Architect & Data Engineer certifications. He specializes in building custom LLM & autonomous AI agents, RAG pipelines, Next.js/React PWAs, Python (Django/FastAPI), Go microservices, and serverless cloud infrastructure on Google Cloud Run and AWS.

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