Senior Software · AI Engineering · Technical Leadership

I build the whole system, from backend to AI.

My work covers backend systems, full-stack products, and production AI: autonomous agents, RAG pipelines, and LLM workflows wired into real products. As Co-Founder & CTO of Relu Interactives, I lead teams and built Relu Spatial across its backend and engine.

Portrait of Caleb Mantey
Caleb Mantey Senior Engineer · Co-Founder & CTO
7+
Years shipping software
Agentic
AI systems & LLM workflows
6+
Industries delivered in
2×
National innovation awards
Selected work

Products & systems I've built

Backend architecture, full-stack delivery, and AI features across immersive tech, industrial operations, health, workforce, and payments.

Flagship · Platform engineering

Relu Spatial

I'm the platform's lead engineer and built it across backend services and the real-time 3D/XR engine. Creators build in a desktop editor with an AI assistant for scripting, 3D layout, and game logic, then publish to web, mobile, and headsets in one click.

Node.js / NestJSPythonWebXR / Three.jsPostgreSQLRealtime / WebRTCLLM-assisted
Visit Relu Spatial ↗
Real gameplay
A game I built end to end

Akofena: Blades of the Ancestors

Real-time fights in the browser.

A free online fighting game, from the 3D client to the server. Matches run on a deterministic simulation with rollback netcode over WebRTC. The server shares that simulation and re-runs ranked matches to check the results.

  • 60 HzDeterministic sim
  • RollbackOver WebRTC
  • RankedRe-run on the server
  • Node.jsHono and PostgreSQL
Mobile · Ride-hailingDropin Driver app onboarding screen: negotiate your fare
Senior Engineer · Contract

Dropin

A ride-hailing app for Ghana with rider and driver apps. I managed the development team and wrote code across the stack. Riders book city trips, airport pickups, or staff transport, and agree the fare with the driver.

NestJSWebSocketsPostgreSQLDockerFlutter
Visit Dropin ↗
Zenjob website homepage
AI · Workforce platform

Zenjob AI Workflows

Built AI-powered matching and workflow-automation features for a European staffing platform, connecting LLM capabilities to real product and operational processes.

About Zenjob ↗
Health technology

besaCare

Contributed architecture and mobile engineering to a healthcare-access platform with appointment booking, video consultations, and health records.

View on Play Store ↗
eGotickets website homepage
Backend · Payments

eGotickets

Maintained and extended a Ruby on Rails ticketing & events platform, adding product features, payment integrations, and deployment workflows.

Visit platform ↗
joy_ussd_engine repository on GitHub
Open source · Ruby

joy_ussd_engine

An open-source Ruby library for building text-based apps across USSD, WhatsApp, Telegram, and similar channels. Other developers build on it.

Explore repository ↗
Climate & health tech

Mission-driven systems

At Think-it, built and maintained scalable, AI-integrated applications for climate- and health-technology partners, with strong testing and documentation.

About Think-it ↗
AI Engineering

I build agentic AI systems

I build the agents behind AI products. From autonomous, tool-using agents to RAG pipelines and production LLM workflows, I design systems that reason, call tools, and act on real tasks.

Autonomous agents

Goal-driven AI agents

Agents that plan, reason, and execute multi-step tasks using tool-calling, memory, and self-correction.

Orchestration

Multi-agent systems

Coordinated agents that delegate and verify each other's work using orchestrator–worker and graph workflows (LangGraph).

Retrieval

RAG & knowledge

Grounding LLMs in private data with retrieval-augmented generation, embeddings, vector search, and semantic memory.

Tool use

Tools & MCP

Connecting agents to real APIs, systems, and the Model Context Protocol so they can act across tools end-to-end.

LLM engineering

Prompting & evals

Structured outputs, function calling, guardrails, and evaluation across OpenAI, Anthropic Claude, and open models.

Integration

AI in the product

Putting AI inside the workflows people already use, with logging, monitoring, and cost limits in production.

Open source & teaching

Building in the open

I publish reusable libraries and developer tools, and I teach what I build, from clean-architecture practices and design patterns to Unity developer tooling and hands-on tutorials.

joy_ussd_engineSOLID principlesDesign patterns Unity developer toolsTechnical writingYouTube tutorials

Teaching the craft

I share practical tutorials on YouTube, including a Unity series that builds a third-person bow and arrow system one mechanic at a time.

Engineering stack

From backend to AI

Backend & data

Ruby on RailsNode.jsNestJSPython / FastAPIREST APIsPostgreSQLMySQLRedis

Frontend & mobile

TypeScriptReactNext.jsAngularFlutterReact Native

AI engineering

OpenAIAnthropic ClaudeLangChainLangGraphRAGVector DBsMCPVercel AI SDK

Delivery & infra

DockerAWSDigitalOceanGitHub ActionsCI/CDAutomated testingTechnical leadership
Founder & technical leader

Building a product company

I co-founded Relu Interactives in Ghana and run its engineering. I set technical direction, build core platform systems, coordinate designers and engineers, and carry products from early decisions through delivery.

For Relu Spatial, I built the backend and engine behind a 3D/WebXR creation platform with AI-assisted authoring, an editor, and cross-device publishing. Through it I've run product planning, client delivery, and the team itself.

Relu Spatial · type a prompt, play the game in seconds
Recognition

Awards from building Relu

National recognition for the startup I co-founded and the products our team ships.

NEIP Presidential Pitch award
2023 · National award

NEIP Presidential Pitch, Overall Winner

Relu's petroleum-engineering simulation won Ghana's Presidential Pitch competition.

Read the award story ↗
Ghana Innovation and Startup Award
2023 · Startup award

Animation/Gaming Startup Innovation of the Year

Relu Interactives won this category at the Ghana Innovation & Startup Awards.

See award coverage ↗
Experience

Engineering across domains

Co-Founder & CTO · Relu Interactives

2022–Present

Lead Relu Spatial engineering across backend, engine, and platform systems, and set technical direction across platform and client work.

Full-Stack & AI Software Developer · Zenjob

2024–2025

Built AI-enabled product and operational workflows, integrating LLM tooling into an existing workforce platform.

Software / AI Engineer · Think-it

2023–2025

Delivered scalable, AI-integrated systems for climate- and health-technology partners.

Software Engineer · Encodev Labs / eGotickets

2020–2023

Built web, mobile, ticketing, and payment capabilities on Ruby on Rails and supporting services.

Senior Software Engineer (Contract) · Dropin

2019–2020

Managed the development team for a ride-hailing app and wrote code across the stack.

Software Developer · Stanbic Bank Ghana

2019

Implemented frontend and backend features for banking applications.

Work together

Work with me on your next system

I design the system, ship the product, and add AI where it saves your team time.

Also see: Full portfolio (all skills) · XR & Game Development →