Charles Mark
Charles Kojo Markportfolio.charlesmark.tech
Available for Engineering Roles & Projects
Senior Backend Engineer | AI Integration & DevOps

Building reliable backend services, AI workflows, and cloud applications.

Backend and AI engineer with 4+ years of experience building production systems — from core APIs and payment integrations to automated AI workflows and cloud deployments. Proven track record of improving performance and maintaining high reliability for over 500k users.

PythonFastAPIDjangon8nClaude APIPostgreSQLSupabaseRedisDockerGCP
Featured ProjectsWork ExperienceWhatsApp
Charles Kojo Mark
Charles Kojo Mark
Backend & AI Automation
Nigeria (Remote)
99.9%System uptime record
40% FasterAPI performance gain
500k+Active users served
4+ YearsSoftware development
Featured Work & Open Source6 Public Repositories

Featured Projects & Production Systems

Real-world applications spanning multi-agent AI systems, document search tools, marketplace APIs, and automated server infrastructure.

AIFeatured
View Code

Klinik

Voice-Enabled Clinical AI Consultation System

An automated clinical intake pipeline powered by 8 specialized LangGraph agents and Llama 3.1 70B, enabling real-time voice consultation and structured patient summaries.

Key Features & Results:
Multi-agent workflow with 8 specialized diagnostic sub-agents
High-speed model inference running on enterprise GPU hardware
Real-time speech-to-text audio ingestion with structured clinical note generation
Integrated Prometheus and Grafana dashboards for latency and usage tracking
Performance Highlight13.68s complete consultation pipeline with live telemetry
LangGraphJavaScriptLlama 3.1 70BvLLMAMD ROCmPrometheusGrafana
AIFeatured
View Code

Smart Doc Assistant

Intelligent Document Q&A Assistant

A fast retrieval-augmented generation (RAG) assistant that allows users to query dense technical PDF documents and get accurate answers with exact page citations.

Key Features & Results:
Semantic search combining vector embeddings with keyword matching
Verifiable source citations to ensure accurate, grounded answers
FastAPI backend providing asynchronous API endpoints
Clean interactive Streamlit interface for quick document upload and chat
Performance HighlightSub-second answer generation with Pinecone vector search
PythonLlamaIndexLangChainPineconeGroqFastAPIStreamlit
Backend
View Code

GigFlow

Freelance Marketplace API with Real-Time Chat & Payments

A full-featured backend API for a freelance platform, handling project proposals, milestone escrow payments, and live real-time messaging between clients and freelancers.

Key Features & Results:
Real-time messaging and contract updates using Socket.io and Redis
Secure milestone escrow payments with Paystack webhook verification
Role-based access control protecting contracts and dispute workflows
Tested MongoDB database schema with atomic transaction handling
Performance HighlightReal-time WebSocket chat and Paystack payment verification
Node.jsTypeScriptExpressMongoDBRedisSocket.ioPaystack
Backend
View Code

FastAPI URL Shortener

Fast URL Shortener API with Analytics & Rate Limiting

A high-performance URL shortening service with sub-millisecond redirect speeds, API rate limiting to prevent abuse, and click analytics.

Key Features & Results:
Two-tier caching strategy using Redis for fast redirects and MongoDB for storage
Rate-limiting middleware to protect the service against spam and abuse
JWT user authentication and personal API key generation
Click analytics tracking referrers, locations, and device types
Performance Highlight<1ms redirect speed with Redis caching
PythonFastAPIMongoDBRedisJWTDocker
DevOps
View Code

Django Production Starter

Production-Ready Django REST API Starter

A well-structured boilerplate for building scalable Django REST APIs, pre-configured with authentication, automated background tasks, Docker containers, and CI/CD.

Key Features & Results:
Docker setup for local development and production deployment
Background job scheduling with Celery and Redis
JWT token authentication and granular user permission classes
Automated GitHub Actions workflow running tests and code checks on every push
Performance HighlightDocker container setup with automated GitHub Actions testing
DjangoDRFPostgreSQLCeleryDockerGitHub ActionsRedis
DevOps
View Code

System Health Monitor

Lightweight Linux Server Health & Alerting Tool

A clean Bash monitoring script that tracks server CPU, memory, disk usage, and failed login attempts, automatically sending alerts and reports.

Key Features & Results:
Monitors CPU, RAM, and disk storage directly from the Linux system
Detects repeated failed SSH login attempts and sends security alerts
Configurable notification alerts via webhook (Slack/Discord) or email
Automated log rotation and disk cleanup to keep servers running smoothly
Performance HighlightZero external dependencies • Automated daily scheduling via Cron
ShellBashLinux SyslogCronWebhook Integrations
Career Timeline

Professional Work Experience

Hands-on engineering roles building production software for international startups, high-traffic consumer platforms, and developer education programs.

Lead Backend Engineer

Current Role
Job Drone Ltd
Jan 2025 – PresentUnited Kingdom (Remote)

Lead backend engineer building automated data ingestion, payment integrations, and cloud infrastructure on Google Cloud.

Built an automated data pipeline processing 100+ job listings per week, completely eliminating manual data entry.
Engineered Stripe and PayPal payment systems with webhooks and audit logging, ensuring zero duplicate charges.
Designed secure authentication and permissions (JWT, Google OAuth, OTP) protecting 60+ API endpoints.
Built automated zero-downtime deployment pipelines on GCP Cloud Run with automated rollbacks.
Mentored junior engineers on API best practices, unit testing, and production incident response.
FastAPIPostgreSQLGCP Cloud RunDockerGitHub ActionsStripePayPal

Backend Engineering Instructor & Curriculum Lead

Mentorship
Innovation Growth Hub
Aug 2024 – Present (Part-time)Aba, Abia State, Nigeria

Led backend engineering training and mentored 50+ students in modern software development and API architecture.

Designed and delivered practical curriculum covering REST APIs, database modeling, Git workflows, and system design.
Built internal learning platform tooling to automate student code reviews and assignment test runs.
Mentored students who successfully secured engineering roles at technology companies across West Africa.
FastAPIDjangoNode.jsPostgreSQLGit WorkflowsAPI Design

Backend Engineer

Somie's Logistics
Sep 2024 – Dec 2024Lagos State, Nigeria

Developed automated document search and intelligent customer support routing pipelines.

Built an automated document ingestion pipeline processing 200+ operational records with instant text search.
Created an AI query routing system with automatic responses and seamless handoff to human support staff.
Reduced customer support resolution times from several hours down to under 2 minutes.
PythonFlaskPostgreSQLn8nSupabaseVector Search

Backend Engineer

OJM Electrical Company
May 2024 – Aug 2024Abia State, Nigeria

Built a geolocation-based booking platform connecting clients with available electricians.

Engineered a location-based matching engine that calculated technician proximity, cutting booking errors by 45%.
Improved API response speed by 40% through database query optimization and Redis caching.
Implemented an automated notification system for appointment confirmations and dispatch updates.
DjangoPostgreSQLRedisCeleryREST APIs

Backend Engineer (Sole Developer)

500k+ Users
RealNaijaGist
Jan 2023 – Apr 2024Aba, Abia State, Nigeria (Remote)

Sole backend engineer managing the database, APIs, and media infrastructure for a high-traffic news platform.

Managed and scaled the core Django application, maintaining reliability during breaking-news traffic surges.
Optimized PostgreSQL queries and added Redis caching, reducing server CPU load by 35%.
Built an automated image and video processing pipeline with Cloudinary for fast media delivery.
Maintained 99.9% platform uptime through regular monitoring, log analysis, and rapid troubleshooting.
DjangoDjango REST FrameworkPostgreSQLRedisCloudinaryNginx
Core Skills & Technologies

Technical Skills & Tools

Key programming languages, backend frameworks, AI automation tools, and cloud platforms I work with.

AI Automation & LLM Orchestration

Multi-agent workflows, autonomous pipelines, inference engines, and protocol tools

n8n (Self-Hosted & Cloud)
Expert
Claude API & Claude Code
Expert
Model Context Protocol (MCP)
Advanced
LangGraph (Multi-Agent Graphs)
Advanced
LangChain & LlamaIndex
Advanced
vLLM High-Throughput Inference
Advanced
RAG Pipeline Architecture
Expert
Pinecone / Qdrant Vector DBs
Advanced
AMD ROCm / GPU Accelerators
Intermediate

Backend Frameworks & APIs

Production API servers, microservices, and asynchronous gateways

FastAPI (Async Python)
Expert
Django & Django REST Framework
Expert
Flask Microservices
Advanced
Express.js / Node.js
Advanced
Next.js App Router (Fullstack)
Advanced

Databases & Persistence

Relational, in-memory, document, and vector persistence layers

PostgreSQL (Schema & Indexing)
Expert
Supabase (Auth & Postgres)
Expert
Redis (Caching, Pub/Sub, Locks)
Expert
MongoDB
Advanced
pgvector & Vector Search
Advanced
Cloudinary Media Pipeline
Advanced

Asynchronous & Queue Systems

Event-driven architecture, distributed job queues, and streams

Celery & Celery Beat
Expert
Redis Pub/Sub & Queues
Expert
Apache Kafka
Advanced
RabbitMQ
Advanced
BullMQ / Task Workers
Advanced

Cloud & DevOps Infrastructure

Reproducible containerization, zero-downtime CI/CD, and cloud hosting

Docker & Docker Compose
Expert
GitHub Actions CI/CD
Expert
GCP Cloud Run
Advanced
AWS (ECS, S3, IAM, EC2)
Advanced
Terraform (IaC)
Advanced
Nginx Reverse Proxy & SSL
Advanced
Vercel Edge Platform
Expert

Observability, Security & Testing

Monitoring metrics, security boundaries, and automated test coverage

Prometheus & Grafana Telemetry
Advanced
OAuth2 / JWT / RBAC / OTP
Expert
Webhook Idempotency & DLQs
Expert
Pytest (Unit & Integration)
Expert
Structured JSON Logging
Expert
Locust Performance Testing
Advanced
Academic Background

Education & Degrees

Bachelor of Science / B.Tech in Software Development

Aug 2022 – Jul 2025
IU International University of Applied Sciences, Germany • Germany (Distance / Remote)

Distributed Systems, Software Architecture, Relational Database Engineering, and Scalable Cloud Systems.

Computer Software Engineering

Jan 2021 – Feb 2023
Saylor Academy • United States (Online)

Core CS principles, algorithms, data structures, and object-oriented software engineering.

O Level, Information Technology

2015 – 2018
Keta Senior High Technical School • Ghana

Foundational computer science, programming fundamentals, and technical computing.

Certifications

Industry Certifications

Core AI Tooling

Crash Course: MCP For Beginners

Anthropic Model Context Protocol (MCP) • 2026

Skills: Model Context Protocol, Claude Code, Client-Host-Server Architecture, Local & Remote MCP Tools

Professional Specialization

Meta Backend Developer Professional Certificate

Meta (Coursera) • 2024

Skills: Python, Django Web Framework, REST APIs, PostgreSQL, Version Control, System Design

Applied Systems

Applied AI & Forward Deployed Systems

Educative.io • 2024

Skills: LLM Orchestration, RAG Architectures, Vector Databases, Embedded Systems Delivery

Get in Touch

Let's Build Great Software Together.

Whether you are looking to hire for an engineering role, automate key workflows, or discuss a new project — I am always open to conversation.

Direct Phone+234 708 236 7382
Chat on WhatsAppSchedule Call (Cal.com)charlesmark.tech