Jannik Semmelhaack
CEO & Founder, VOIDS
Jannik founded VOIDS to solve one of e-commerce's largest operational inefficiencies: procurement and inventory management. Today, more than 250 brands use VOIDS to automate demand forecasting, purchase planning, and inventory optimization.
Before VOIDS, Jannik studied at TU Munich and WHU. The first customer relationship with FC Bayern Munich came through the Techstars network and became the starting point for the company.
His focus is the intersection of AI, operations, and e-commerce. He writes about demand forecasting, inventory management, and supply-chain strategy for DTC brands.
Articles by Jannik Semmelhaack
Purchasing Marketing Inventory Forecast: A Practical 2026 Guide
Build a purchasing marketing inventory forecast that connects campaigns, demand, stock and purchase orders. Learn the 2026 process.
AI Tools for Ecommerce Demand Forecasting: A Practical 2026 Guide
Compare AI tools for ecommerce demand forecasting by data, workflow and inventory fit. Use the 2026 criteria to choose your next step.
How to Automate Forecasting and Replenishment from Spreadsheets
Learn how to automate forecasting and replenishment from spreadsheets, choose the right workflow, and plan a practical migration.
How to Replace Excel for Inventory Planning in 2026
Replace Excel for inventory planning with a structured forecasting workflow. Compare options, migration steps, risks, and next actions.
Replenishment Planning and Cash Flow for DTC Brands
Learn how replenishment planning protects DTC cash flow, connects forecasts to purchase orders, and supports smarter stock decisions.
Shopify 3PL Inventory Planning: Architecture, Workflow and Selection Guide for 2026
Master Shopify 3PL inventory planning with a clear workflow, architecture criteria and software options. Build a practical planning process.
Stocky Shutdown Shopify Inventory Planning: How to Replace Stocky in 2026
Stocky shutdown Shopify inventory planning explained: compare workflows, risks and replacement criteria for 2026. Start your evaluation.
Out of Stock Costs Calculator: Definition, Workflow, Examples and Decision Criteria 2026
Use an out of stock costs calculator to estimate lost demand, margin impact and planning risk. Learn the workflow and next steps.
Out of Stock Effects: Definition, Costs, Forecasting and Replenishment Priorities
Understand out of stock effects, stockout costs and lost sales ecommerce risks. Learn what to measure and fix first in 2026.
Stocky Alternative for Shopify: Decision Guide for Inventory Planning in 2026
Need a Stocky alternative for Shopify? Compare forecasting, replenishment and PO workflows for 2026. Choose the right tool.
Inventory Planning Software for Shopify Brands: Connect Forecasting, Replenishment, and Purchasing
Inventory planning software for Shopify brands: criteria, data model, integrations, and workflows for forecasting and replenishment.
Demand Forecasting in E-Commerce: The Ultimate Guide for 2025
Learn how AI-powered demand forecasting boosts your e-commerce revenue and cuts inventory costs. Practical guide with strategies, tools, and case studies.