Hani Barkallah Senior Full Stack Software Engineer
Phone
+216 92298888
in/hani-barkallah-20448a166
Summary

Flexible senior full stack engineer with 7+ years delivering across the full stack— backend (Elixir/​Phoenix, Laravel), web (React, Vue.js), mobile (React Native), and desktop (Electron). Comfortable moving between product surfaces and infrastructure: real-time platforms, billing/​FinTech, public APIs, cloud-native AI, and production ops. At Ovice, shipped features end-to-end for web, React Native mobile, and Electron desktop while scaling systems to 20–60k daily active users. Adaptable engineer who picks up new domains quickly and owns work from design through deployment.

Skills
  • •Languages & Frameworks: Elixir (Phoenix/​Oban), PHP (Laravel), Javascript, Typescript, Node js, React, React Native, Expo, Electron, Vue.js, Laravel Livewire, Webrtc.
  • •Real-Time & Data: WebSockets, Laravel Echo Server, Google BigQuery, Airbyte (data synchronization), Redis, PostgreSQL, MySQL.
  • •Cloud & Infrastructure: AWS (Amplify Gen 2, Lambda, DynamoDB, S3), ArgoCD, Kubernetes.
  • •API & Security: Public API design, plugin architecture (Iframe/​SDK), SAML/​SSO, Stripe payments.
  • •Observability: Datadog, Redash, Sentry, OpenTelemetry.
Projects

React Screen Flow⁠

Typed workflow engine for React screen-based applications

React Screen Flow is a typed workflow engine that helps developers orchestrate multi-screen experiences in React applications. It centralizes flow rules, validates navigation, handles async guards, and integrates with router-backed flows while leaving business state management to the application.

Professional Experience

SENIOR FULL STACK Engineer

OVICE
03/2020 – Present | remote
  • •Plugin ecosystem architecture: Designed and led a secure plugin architecture for a real-time virtual workspace—iframe sandboxing, window.postMessage messaging, and developer integration patterns. (example repo: https://github.com/oviceinc/custom-plugins⁠ ,https://github.com/oviceinc/custom-plugin-client⁠)
  • •Billing & FinTech systems: Stripe-based billing and subscriptions with upgrades, downgrades, proration, invoicing, payment failures, retries, and state reconciliation.
  • •Public API: Workspace integration API with security, versioning, rate limiting, and OpenAPI docs for third-party integrations. (API docs)
  • •Cloud-native feature development: OpenAI-powered Q&A and PDF summarization on AWS Amplify Gen 2, Lambda, DynamoDB, and React — https://app.inforea.ch/⁠
  • •External API & embeddable AI assistant platform: Multi-tenant API with API-key auth, token/​org lifecycle, quotas, usage reservation, and failure-safe rollback.
  • •Real-time systems & background processing: Phoenix Channels and Oban (cron, backfills, cleanup) for virtual spaces serving 20–60k DAU.
  • •Data export & compliance (MySQL & BigQuery): Streaming CSV exports for user lists and message logs—millions of records, owner-only access, password-protected delivery for audit/​compliance.
  • •Performance optimization: 10–20% system-wide improvements via query tuning, caching, and frontend request reduction.
  • •Monitoring & reliability: 60% reduction in production alert noise via Sentry and stability improvements.
  • •Product stability & retention: High-impact reliability improvements targeting key user pain points and churn reduction.
  • •Mobile app (React Native) — real-time & authentication: Firebase push notifications, React Native WebRTC (aligned with browser), SAML/​SSO deep linking for seamless mobile login.
  • •Electron desktop application: Deep linking and mic/​camera permissions for in-app voice/​video and screen sharing.
  • •Platform migration: Laravel + Vue.js → React + Phoenix/​Elixir with feature-flag routing and dual-system API compatibility.
  • •Feature delivery & release management: Feature flags for safe rollouts, controlled testing, and gradual adoption in hightraffic environments.
  • •Deployment & observability: ArgoCD/​Kubernetes rollouts; Datadog and Redash for API, DB latency, and Oban job health.
  • •Production debugging: Diagnosed memory/​CPU pressure in K8s via live pods, remote execution, and Erlang observer CLI under production traffic.
  • •Enterprise security: SAML-based SSO for identity provider integration and centralized access control.
  • •Platform engineering & internal tools: Customer success platform for enterprise accounts, orgs, users, billing, and largescale CSV exports.
  • •Engineering ownership: End-to-end ownership from system design through production deployment with product and cross-functional teams.

    • R&D Software Developer

    WILL GROUP, JAPAN|HRDTABANK
    07/2019 – 01/2020 | Monasitr

    •Automation: Optimized Google’s OCR for ID card recognition and built high-volume web scraping systems using JCrawler and JSOUP.

    •Tech Stack: Angular 7, Spring Boot, WebRTC, PostgreSQL.

    R&D Software Developer

    SAINT MEDIA JAPAN|HRDTABANK
    2018 – 2019 | Monastir
  • •Blockchain & Automation: Developed Ethereum-based ERC20 smart contracts via Solidity and created internal time-tracking and automation tools.
    • Languages
    • •English, Upper Intermediate (B2)
    • •French, Intermediate (B1)
    • •Arabic, Nativ
    Education

    National Engineer's Degree, Computer Engineering

    Esprims
    09/2015 – 06/2018 | Monastir

    Higher Technician's Degree, Computer Systems

    ISIMM
    09/2011 – 06/2014 | Monastir