zerofusion — Architecture & Engineering Blueprint

Layered Pipeline

End-to-End Infrastructure Flow

1. Edge & Security

Cloudflare Edge Proxy

Universal SSL/TLS Strict Edge
WAF IP Rate Limiting (Anti-Abuse)
Header Transform: Ingress Secret Injection
Zero Trust OTP Gating on Staging

Edge Network Layer

2. Serverless Compute

Google Cloud Run (v2)

Scale-to-Zero ($0 Baseline Idle Cost)
Ingress Secret Validation Middleware
FastAPI, Uvicorn & Gunicorn Engines
Isolated Service Accounts per Service

Microservice Layer

3. Serverless Storage

SQLite + Litestream & GCS

Litestream Continuous SQLite Backup to GCS
Auto-Purge GCS Uploads (24h Lifecycle)
Firestore Pro License Verification
RAM-only Processing for CV Engine

Persistence Layer

4. AI Intelligence

Google AI Studio

Gemini Vision Engine
Strict Dynamic Pydantic Schemas
15 RPM / 1M TPM Zero-Cost Operation
Autonomous Multi-Agent Tool Chains

Intelligence Layer

Microservice Specifications

Component Architecture Breakdown

AutoDoc Enterprise

Docker / Air-Gapped

An air-gapped on-premise document automation platform built for corporate legal, HR, and finance departments. Merges datasets into pre-approved Word templates locally with zero data egress.

// Architectural Highlights

• Core Engine: Python 3.13, Django 5, docxtpl

• Security: 2FA TOTP Vault (/autodoc-vault-admin-99/)

• Licensing: Outbound HMAC ping to Firestore Function

• Isolation: 100% in-memory CSV-to-DOCX compilation

Delivery Model: Public Google Artifact Registry Docker Image

Unstruct DaaS Engine

FastAPI / Gemini Vision

A high-throughput multimodal document parsing engine converting unstructured invoices and scanned forms into strictly typed Pydantic models with dynamic runtime schemas.

// Architectural Highlights

• Core Engine: FastAPI, Uvicorn, Pydantic v2

• Model: Google AI Studio Gemini Free Tier (google-genai)

• Zero-Cost DB: SQLite + Litestream streaming replication to GCS

• Rate Limiting: SHA-256 salted IP hash tracking

Deployment: Serverless Google Cloud Run with single-instance DB safety

CV Maker Studio

RAM Engine / WeasyPrint

An in-memory resume building and PDF compilation platform with bidirectional visual canvas editing, live HTML/CSS synchronization, and rich layout parsing.

// Architectural Highlights

• Compilation Engine: WeasyPrint (A4 pixel-perfect CSS)

• Ingestion: pdfplumber structure & margin parsing

• WYSIWYG: Iframe contentEditable & code bidirectional sync

• Security: In-memory streaming (0 bytes stored on disk)

Subdomain: cv.zerofusion.dev

IaC & Keyless CI/CD

Terraform / WIF OIDC

Infrastructure-as-Code monorepo providing reproducible staging and production environments on GCP with zero long-lived service account credentials.

// Architectural Highlights

• Terraform: Workspace isolation (staging vs production)

• Remote State: Native GCS backend with automatic state locking

• CI/CD: GitHub Actions via Workload Identity Federation (WIF)

• Secrets: Secret Manager runtime injection to Cloud Run

Security: Keyless OIDC token exchange (No static JSON keys)

Engineering Standards

Complete Technology Matrix

Domain / Layer	Technologies & Libraries	Architectural Purpose
Cloud & Serverless	Google Cloud Run (v2), Artifact Registry, Cloud Functions	Container execution, auto-scaling, scale-to-zero when idle
Edge & DNS	Cloudflare WAF, Transform Rules, Zero Trust OTP	Edge rate limiting, SSL termination, ingress secret verification
Backend & API	Python 3.13, FastAPI, Django 5, Uvicorn, Gunicorn	REST endpoints, HTMX HTML partials, session and OTP management
AI & Processing	Gemini 2.5 Flash, google-genai, WeasyPrint, docxtpl	Multimodal document parsing, in-memory PDF/Word compilation
Data & Storage	SQLite, Litestream, Google Cloud Storage, Firestore	Continuous SQLite replication, temporary upload buckets, licensing DB
DevOps & Security	Terraform, GitHub Actions, Workload Identity (OIDC), Secret Manager	Keyless CI/CD deployments, remote state locking, secret injection