Senior Backend Developer

Zelh is a fast-growing, passionate outsourcing company.

Our mission is to be the most reliable company by offering and maintaining consistently high-quality services.

We achieve the mission by fostering long-term relationships with customers, employees, and vendors. Personal attention, timely communication, and respect for all people are the basis of our business philosophy!

Now we are looking for Senior Backend Developer for one of our logistics client. The company is making a SMB version of this TMS and has 60% of it done, but need to finish the project. This will require a code review and clean up, revising the UI for mobile, desktop, Andriod/IOS app, as well as using LLM and Chatbot to build out features.
An ideal candidate will utilize AI agents to support daily coding tasks (e.g., ChatGPT, Claude, Anthropic), and be familiar with LLMs and AI-based projects.

• 3+ years backend development in PHP/Laravel

• Experience building and maintaining RESTful APIs: need to understand how to expose TMS business logic cleanly, especially for the chatbot layer

• Laravel Authentication systems (OAuth, Sanctum, or Passport)

• Proven experience working in existing producƟon codebases. Not just greenfield builds (need specific examples)

• PostgreSQL or MySQL at a deep level — migrations, indexing, query optimization, handling live data while making schema changes

• Experience with feature removal and refactoring in live systems

• Experience with Microsystems

• Git proficiency — branching strategy, code reviews, commit discipline (Need someone who keeps the repo clean when working across two products)

• Experience with multi-tenant SaaS architecture

• Has built or maintained webhook and event-driven systems (real-time shipment status updates, automation)

• Understands API rate limiting, and role-based access control (multiple products will have different user permission structures/layouts)

• Experience with queue systems like Redis, Bull, or RabbitMQ

• Experience with third-party integrations (ELD systems, carrier APIs, mapping/routing, QuickBooks, Twilio, Mailgun, etc)

• Experience with push notification infrastructure (Firebase Cloud Messaging or Apple Push Notification Service)

• Experience building APIs that handle offline sync (mobile apps need to reconcile actions taken without connectivity)

• Has built API endpoints that serve as tools for an LLM (they understand funcƟon calling architecture, not just that it exists)

• Experience with document processing pipelines (receiving, storing, and rouƟng documents to an OCR service and handling the response)

• Understands prompt injecƟon risks and input validaƟon when user input is being passed to an LLM

• Comfortable working with Anthropic or OpenAI SDKs at the API level, not just through wrappers
  

• Working hours: flexible, but with American time overlap

• Working mode — remote/hybrid

• 20 days of PTO, 11 days of National Holidays and 3 sick leaves

• Equipment provided

• Tax coverage