# Career & Professional Experience — Mohammad Shadikur Rahman

> **Headline**: Software Engineer · AWS · DevOps · Platform & AI Infrastructure
> **Location**: Hamburg, Germany
> **Email**: hello@shadikur.com

## Overview
I am a software engineer with extensive experience across cloud infrastructure, DevOps, backend development, systems engineering and automation. At OTTO in Hamburg, I modernize AWS infrastructure using AWS CDK and TypeScript, develop reusable constructs, and integrate automated delivery through GitLab CI/CD and GitHub Actions.

My background spans Azure and Active Directory, Linux and Windows Server administration, PowerShell and shell automation, networking, Docker, enterprise communications and more than 200 PBX deployments. I focus on turning complex infrastructure into secure, observable and maintainable systems that other engineers can reuse.

Alongside my core work, I build practical AI infrastructure for local large language models and conversational voice agents using GPU-accelerated inference, Whisper, LiveKit, Docker and workflow automation. The common thread is end-to-end ownership: architecture, automation, deployment, monitoring, documentation and reliable production operation.

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## Software Engineer — OTTO
- **Period**: Dec 2024 — now
- **Location**: Hamburg, hybrid
- **Tech Stack**: AWS, AWS CDK, TypeScript, Lambda, API Gateway, DynamoDB, S3, IAM, CloudWatch, GitLab CI/CD, GitHub Actions, Infrastructure as Code

### Key Responsibilities & Achievements
- Modernize AWS infrastructure by migrating Serverless Framework and Terraform workloads to AWS CDK and TypeScript.
- Develop reusable infrastructure constructs for Lambda, API Gateway, S3, DynamoDB and other AWS services.
- Design secure, scalable infrastructure patterns for microservices and multiple deployment environments.
- Integrate infrastructure deployment and testing with GitLab CI/CD and GitHub Actions.
- Apply IAM least-privilege, resource tagging, monitoring and Infrastructure as Code best practices.
- Collaborate with software engineers, DevOps specialists and architects to improve platform reliability and developer workflows.
- Create reusable libraries and modules that standardize infrastructure delivery across teams.

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## IT System Engineer — Guidepoint
- **Period**: Nov 2019 — Jun 2024
- **Location**: Düsseldorf
- **Tech Stack**: Azure AD, PowerShell, Microsoft Teams, OpenSIPS, Avaya, Windows Server, Linux

### Key Responsibilities & Achievements
- Owned on-site networking and hardware infrastructure end to end: replacement, maintenance, monitoring.
- Ran Microsoft Azure and Active Directory across on-premises and cloud.
- Managed Teams telephony over Direct Routing with an SBC, and supported Avaya IP Office PBX for other offices.
- Automated deployment and configuration with PowerShell on Windows and shell scripts on Linux; deployed an OpenSIPS SBC for Teams.

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## Full Stack Engineer — count7
- **Period**: Feb 2015 — Apr 2019
- **Location**: London
- **Tech Stack**: Asterisk, FreeSWITCH, PHP, MySQL, JavaScript, Cisco, MikroTik, VoIP

### Key Responsibilities & Achievements
- Installed and configured 200+ FreePBX (Asterisk) and FusionPBX (FreeSWITCH) systems, with custom modules per customer.
- Led the backend team on the core API; built the company CRM and VoIP billing in PHP, MySQL and JavaScript.
- Deployed and maintained Cisco, Netgear and MikroTik gear on customer sites.
- Trained customer IT administrators on cloud PBX maintenance and handled 2nd/3rd line support.

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## QA Engineer — SBSystem UK
- **Period**: Dec 2010 — Oct 2013
- **Location**: London
- **Tech Stack**: Selenium, Java, Docker, Jenkins, Jira, Test Automation

### Key Responsibilities & Achievements
- Wrote and ran Selenium WebDriver suites against Java products, from functional cases through performance.
- Set up and maintained test environments in Docker; automated build and deploy through Jenkins.
- Tracked defects in Jira and worked defect triage directly with developers.

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## Education & Background
- **MEng Mechatronics Systems Engineering** (2019 — 2022) at Rhine-Waal University: Specialised in automation. Microcontrollers, control systems, advanced programming. Robotics and Formula One clubs.
- **Electronics & Communication Engineering** (2019) at Ravensburg-Weingarten University — exchange: DSP, RF and antenna design, embedded systems, wireless communication.
- **ISEFP, Aerospace Engineering** (2012 — 2015) at Queen Mary University of London: Propulsion, CAD, core electronics and mechanical engineering. Graded 63%.

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## Direct Links & Resources
- **Portfolio Overview**: https://shadikur.com
- **Work & Projects**: https://shadikur.com/work.txt
- **Technical Articles**: https://shadikur.com/blog.txt
- **LLM Full Index**: https://shadikur.com/llms-full.txt