YB

Senior Full-Stack Product Engineer

Youssef
Belhadj

Building production AI & SaaS systems from architecture to deployment. AI SaaS, ERP platforms, EdTech APIs, Flutter apps, and secure cloud infrastructure — owned end to end.

4+
Years shipping production systems
70%
Faster deployments via Docker CI/CD
40%
Faster APIs on MTN Corporate Platform
36
Prisma models in Hesabi ERP
Portrait of Youssef Belhadj

Tunis · Available for senior product engineering roles

TypeScript · Next.js · Node · PostgreSQL · Flutter · AI

Selected work

Systems that shipped — with architecture, impact, and ownership.

Case studies across ERP, EdTech, AI platforms, founding engineering, and hospitality — each with measurable product outcomes.

About

I ship complete products - not just layers.

I'm a Senior Full-Stack Product Engineer with 4+ years building production systems from architecture through deployment. My work spans AI-enabled SaaS, ERP/accounting platforms, school management APIs, mobile apps, fintech backends, and containerized cybersecurity training environments.

I think in product outcomes: who uses it, what must never break, what can be async, and how the system grows without becoming a museum of exceptions. That means backend architecture, database design, REST APIs, dashboards, mobile, AI integrations, Docker infrastructure, and security - owned as one story.

At Campusna I led architecture on scalable SaaS platforms, cut deployment time by 70% with Docker CI/CD, and improved API latency by 40% on a corporate platform. As Co-Founder at DarDev I pair product strategy with technical leadership - shipping systems teams can operate.

Product thinking

Every technical choice maps to a user or business constraint.

Scalability

Schemas, queues, and boundaries designed before the traffic arrives.

Developer experience

Typed APIs, tests, Compose stacks, and docs that make the next change safe.

Leadership

Technical lead energy: clarity, ownership, and delivery with distributed teams.

Security mindset

OWASP-aware design, RBAC, secrets hygiene, and auditability.

AI engineering

LLMs as product leverage - integrated, tested, and operationally sound.

Engineering ecosystem

Not a laundry list — a working system.

Frontend through infrastructure. Pick a layer to see how I build production products.

Frontend

Next.js 15/16React 19TypeScriptTailwindRadix UIshadcnGSAPFramer Motion

Engineering beyond code

Security, mobile, AI, and architecture — treated as product.

Security mindset

OWASP-aware delivery from auth to containers - informed by hands-on cybersecurity lab work across 22,000+ files of Dockerized training environments.

OWASP Top 10

Hands-on labs for SQLi, XSS, SSRF, IDOR, injection, and privilege escalation.

Authentication

JWT, session boundaries, token rotation patterns, and secure auth flows.

Authorization & RBAC

Role-aware APIs across school, ERP, and SaaS domains.

API Security

Rate limiting, signed URLs, input validation, and audit logs.

Docker Security

Multi-stage builds, least privilege, health checks, isolated networks.

Cloud Security

Secrets management, environment isolation, and hardened deploy posture.

Encryption

Crypto-aware services for tokens, sensitive fields, and transport trust.

Secure SDLC

Threat modeling mindset from architecture through tests and release.

Mobile

Flutter products with offline-first thinking, push, and adaptive UI - FitNerve and beyond.

Flutter

Cross-platform product apps with Riverpod state and production polish.

Android & iOS

One codebase shipping native-feel experiences on both platforms.

Offline-first

Local caching patterns so core flows survive flaky networks.

Push & realtime

Firebase messaging and WebSocket-ready architectures.

Adaptive UI

Responsive and adaptive layouts from phone to tablet.

AI engineering

LLMs integrated into recruitment, fitness, and business platforms - with vector-ready data and worker pipelines.

LLM Integration

OpenAI, Gemini, Claude - wired into real product workflows.

AI Workflows

Background jobs, plan generation, scoring, and automation pipelines.

Vector-ready data

PostgreSQL + pgvector for candidate scoring and retrieval paths.

RAG & embeddings

Architecture designed for retrieval-augmented product features.

Prompt engineering

Deterministic enough for production - measurable, testable outputs.

How I design systems

Microservices when isolation pays. Modular monoliths when speed does. Queues, caching, and Docker always in the conversation.

01

Start with the domain

Schema and boundaries follow the business - 36-model ERPs and 43-endpoint APIs exist for a reason.

02

Choose the shape deliberately

Modular monoliths when speed matters; workers and queues when the request path must stay fast; microservices when isolation earns its cost.

03

Async where it hurts

BullMQ/Celery workers for exports, notifications, email, and AI jobs - never block the user on heavy work.

04

Cache and store with intent

Redis for speed and queues; Postgres as source of truth; object storage for files with signed access.

05

Ship operable systems

Docker multi-stage builds, health checks, CI/CD, tests, and observability as part of the product - not afterthoughts.

06

Security is architecture

AuthN/AuthZ, rate limits, audit logs, and threat modeling belong in the first design pass.

Experience

Technical leadership with receipts.

  1. Recent

    Senior Full-Stack Engineer / Technical Lead

    Campusna · Tunis, Tunisia

    • Led architecture and implementation of scalable SaaS platforms with Node.js, Django, Next.js, and TypeScript.
    • Reduced deployment time by 70% via Docker pipelines and automated CI/CD.
    • Designed modular backends and REST APIs; integrated OpenAI and Claude-assisted workflows.
    • Cut API response times by 40% on the MTN Corporate Platform through query optimization and refactoring.
    • Collaborated with distributed Agile teams to ship production features on schedule.
  2. Ongoing

    Co-Founder · Engineering & Product

    DarDev · Tunisia

    • Own product strategy, architecture, and delivery across client and internal systems.
    • Lead AI integration, automation, security posture, and cloud infrastructure decisions.
    • Ship end-to-end: backend, frontend, mobile-ready surfaces, and deployment.
  3. Earlier

    IT Systems Support / Infrastructure

    CSFMT · Hammam-Lif, Tunisia

    • Managed IT infrastructure, network troubleshooting, backups, and monitoring scripts.
    • Maintained hardware/software deployments and organizational technical support.

Education

Holberton School

Full-Stack Software Engineering

CSFMT

Advanced Technician Degree, Information Technology

Also shipped

FitNerve (AI fitness Flutter app), RhAI/EscaHire (AI recruitment with pgvector), PropClose (B2B sales automation), App4Drivers marketplace architecture, and a 22k+ file cybersecurity Docker lab portfolio - detailed on request and in the resume.

Contact

Let's build the next production system.

Open to Senior Full-Stack Product Engineer and founding-engineering conversations. Tunis-based, remote-friendly.

Coming soon

Engineering articles

Architecture deep-dives

Speaking & open source

Testimonials