Senior Full Stack Software Engineer (Mobile + Web) - SaaS Field Operations Platform

We’re a security/field-services SaaS company running a live, revenue-generating platform for 70+ weekly users while simultaneously building its ground-up successor. We need an engineer who can operate independently across the full stack - mobile, backend, frontend, and database - and who is equally comfortable maintaining a legacy production system and building greenfield architecture., * Maintaining and stabilizing our legacy production platform (PHP/Laravel + native iOS/Android), which handles active billing, government/legal compliance obligations, and daily field operations.

• Building our next-generation platform(Python/Django + React + React Native), which will eventually replace the legacy system entirely.

You’ll work directly with the Chief Technology Officer (CTO), who currently operates as sole engineer/architect across both systems - this role is designed to reduce that single point of failure and take ownership of significant chunks of both codebases.

What You’ll Work On

Legacy Platform (current production system)

• Laravel 5.8 / PHP 7.4 monorepo: multiple web apps (customer-facing permit portal, parking operations, HQ, admin/backend), a Laravel REST API, and native iOS/Android mobile apps
• PostgreSQL on AWS RDS, EC2 instances behind an Application Load Balancer, CodePipeline/CodeBuild deployments
• Payment/subscription processing via Authorize.net ARB, transactional email via Postmark
• Bug fixes, incident response, targeted remediation work, and controlled feature changes - this system must stay reliable and compliant while it’s being phased out

Next-Gen Platform (active build)

• Multi-tenant SaaS ERP for managing distributed field/security personnel, clients, and client properties
• Backend: Django 5.0 + Django REST Framework, django-tenants (schema-based multi-tenancy), Celery for background/scheduled jobs
• Frontend: React
• Mobile: React Native (iOS + Android) - this is the platform’s field-worker interface, covering things like shift check-ins, offline data sync, geofencing, and photo capture with EXIF/compression handling
• Data layer: PostgreSQL (Aurora), Redis (ElastiCache) for caching/queues
• Infrastructure: AWS (VPC, ALB, EC2, CodePipeline/CodeBuild/CodeDeploy), JWT-based auth, service-layer architecture with clear separation between views/serializers/business logic

• Mobile app development experience is required - either native iOS/Android or React Native, ideally exposure to both. You should be comfortable with offline-first patterns, background sync, geolocation, and device permissions (camera, GPS).
• True full-stack range: backend API design (REST), relational database design (PostgreSQL preferred), and frontend web development (React).
• Comfort working across two different tech stacks simultaneously (PHP/Laravel legacy + Python/Django modern) without needing everything to be greenfield to do good work.
• Experience with multi-tenant SaaS architecture is a strong plus (schema-based tenancy, tenant isolation patterns).
• AWS familiarity: EC2, RDS/Aurora, ALB, CI/CD pipelines (CodePipeline/CodeBuild or equivalent like GitHub Actions/CircleCI).
• Experience with payment/subscription systems (Authorize.net, Stripe, or similar) is a plus given the legacy system’s ARB-based billing.
• Strong independent judgment. This is a lone-wolf engineering environment - we need someone who asks sharp clarifying questions up front, doesn’t need hand-holding once scoped, and can be trusted with production systems that have legal/compliance weight.

Nice to Have

• Experience with field-service, workforce-management, or security-industry software
• Familiarity with geofencing/location-based features
• Experience migrating a legacy system to a new platform while keeping the old one live
• Comfort with Jira-based sprint workflows (1-week sprints, story-pointed backlog)

Pulled from the full job description

• Paid training
• On-the-job training
• Paid time off
• Paid sick time, Why This Role?
• Direct ownership - you won’t be one of fifty engineers touching a codebase; you’ll be one of two, with real architectural influence
• You’ll see a full legacy-to-modern platform migration from the inside, not just inherit the aftermath

Pay: $60,000.00 - $140,000.00 per year

Benefits:

• On-the-job training
• Paid sick time
• Paid time off

Oculus Systems Security is a forward-thinking security provider dedicated to enhancing safety through innovative technology and proactive physical security measures. We serve communities by bridging the gap between physical security and cutting-edge solutions, working closely with local law enforcement and clients to create safer environments.