Karl M

Python Developer / ERP Implementation Specialist

Toptal

May 2022 - Present • 4 yrs 2 mos

Starting my professional journey as a Python Developer and ERP Implementation Specialist at a software development company, this is where my technical foundation was built, writing clean, efficient Python code and gaining hands-on experience with ERP systems that shaped everything that followed. THE FOUNDATION BEING BUILT Early-stage businesses and growing SMEs needed affordable, functional ERP systems but lacked the technical expertise to implement them properly. They needed developers who could bridge the gap between raw software capability and real business operations, delivering systems their teams could actually use. PYTHON DEVELOPMENT & TECHNICAL GROUNDWORK Developed core business applications and automation scripts using Python, building a strong engineering foundation in object-oriented programming, data modelling and backend logic. This technical depth became the backbone of every Odoo customization and module development that followed in my career. EARLY ODOO & ERP IMPLEMENTATION WORK Gained foundational hands-on experience implementing and configuring Odoo across Sales, Inventory and Accounting modules for SMEs. Learned to map client business processes into ERP workflows, a skill that became central to every project I delivered from this point forward. CROSS-FUNCTIONAL COLLABORATION Collaborated with business analysts, operations managers and end users to gather requirements, configure modules and deliver ERP systems aligned with real operational needs, building the client communication and problem-solving skills that define my consulting approach today.

Odoo Systems Architect & Technical Consultant

Upwork • Freelance

Apr 2021 - Present • 5 yrs 3 mos

As an independent Odoo Systems Architect & Technical Consultant based in Germany, I work with manufacturing companies, e-commerce brands, SaaS businesses and accounting firms to design, build and scale Odoo ERP ecosystems that actually work, not just systems that are installed and left to break. THE PROBLEM I SOLVE Most businesses struggle with disconnected workflows, failed ERP implementations, and systems that can't handle real business complexity. They waste months on generic setups that don't fit their operations, lose money on compliance errors, and end up with Odoo installations that create more problems than they solve. I eliminate that entirely. WHAT I DELIVER I architect custom Python modules tailored to unique business logic, deploy production-grade environments on Odoo.sh, and build deep API integrations with DATEV, DHL, Stripe and third-party platforms. Every solution is engineered for scalability, performance and long-term maintainability, built to grow with your business. GERMAN MARKET EXPERTISE Operating in Germany demands more than technical skills. I ensure full GoBD compliance with audit-proof accounting trails, DATEV export configuration, XRechnung & ZUGFeRD e-invoicing setup, SKR03/SKR04 chart of accounts and ELSTER integration, keeping businesses legally protected and fully audit-ready. E-COMMERCE & B2B PLATFORMS I build advanced B2B multi-website platforms featuring wholesale pricing logic, 3D product visualizations, server-side GTM & GA4 tracking, multi-campaign retargeting funnels, A/B testing, ROAS optimization and full GDPR compliance.

Odoo ERP Developer / Functional Consultant

Odoo • Freelance

Feb 2017 - Present • 9 yrs 5 mos

Working as an Odoo ERP Developer and Functional Consultant at a European ERP consultancy, I led end-to-end implementations across manufacturing, accounting and retail sectors translating complex client requirements into clean, scalable Odoo solutions that delivered measurable operational value. THE CHALLENGE WE SOLVED Most clients came to us with outdated legacy systems, manual processes and completely disconnected departments. They needed an ERP that could unify their operations, reduce costly errors and scale with their growth, without months of disruption to their ongoing business. MODULE DEVELOPMENT & CUSTOMIZATION I developed and customized core Odoo modules across Sales, Inventory, Manufacturing, Accounting, Purchase and HR. Built custom Python extensions to handle unique business workflows that standard Odoo modules could not cover out of the box. CLIENT IMPLEMENTATIONS & ROLLOUTS Managed full-cycle ERP rollouts for clients across multiple industries, from requirements gathering and system architecture through to deployment, user training and post-go-live support. Delivered projects on time across manufacturing plants, retail chains and professional services firms. TEAM COLLABORATION & TECHNICAL LEADERSHIP Worked closely with functional consultants, project managers and client stakeholders to ensure every implementation aligned with business goals. Conducted code reviews, maintained module documentation and supported junior developers throughout project lifecycles.