When you sell in more than one place, stock gets messy fast. Your website says you have five left. The marketplace says three. The physical store sold the last two this morning. A customer orders online, pays and then gets an apology message. Meanwhile, your best-selling item ran out last week and nobody reordered in time.
I'm Aldrian, an independent developer. I build inventory systems and integrations that keep stock accurate, prevent overselling and warn you before you run out.
In my freelance work, I implemented a new inventory tracking system for a small business client that reduced stockouts by 20%. That project taught me that inventory problems are usually process problems first and software problems second, and the best systems fix both.
Common inventory problems
- Overselling when the same stock is sold on several channels
- Stock counts updated by hand, late or not at all
- Stockouts on best sellers because nobody noticed the level dropping
- Too much money tied up in slow-moving stock
- No history of what moved in or out, or why
- Variants, like sizes and colors, tracked inconsistently
- Spreadsheets edited by several people at once
Two approaches
Integrate what you have
If you already use an inventory, POS or ERP system, I can connect it to your website and marketplaces through their APIs, so stock levels sync automatically. More on API integration.
Build a custom inventory system
If your current setup is spreadsheets, or no existing tool fits your process, I can build a focused inventory system around how you work.
What a custom inventory system can include
Products and variants
Every product, size, color and bundle with its own stock level and SKU.
Stock movements
Every change recorded: received, sold, returned, transferred, damaged or adjusted, with who did it and when. No more mystery numbers.
Multiple locations
Warehouses, stores and stockrooms tracked separately, with transfers between them.
Low-stock alerts
Reorder points for each product, with alerts by email or chat when stock drops below them.
Purchase orders
Create purchase orders to suppliers, receive stock against them and track what's still incoming.
Reports
Stock on hand, stock value, fast and slow movers, stock history and sales by product.
Barcode scanning
Scan barcodes with a phone camera or scanner for receiving, picking and counting.
Stock counts
Guided counts with variance reports, so physical stock and system stock match.
Syncing with your sales channels
- Your website store, including WooCommerce and Shopify
- Marketplaces, where they provide APIs for stock updates
- POS systems in physical stores, where they allow integration
- B2B ordering portals. See B2B supplier websites.
When an order comes in anywhere, stock updates everywhere. Safety buffers can hold back a few units per channel to avoid overselling during busy periods.
Built to be accurate
Inventory systems have to handle tricky cases correctly:
- Two orders for the last unit at the same moment
- Orders cancelled or refunded, returning stock
- Bundles that use stock from several products
- Partial shipments and backorders
- Sync failures, with retries and alerts instead of silent errors
I build with these in mind and test them deliberately. Reliability under concurrent activity is something I care about in all my work, including real-time apps like Ghostly.
For WooCommerce stores
WooCommerce tracks stock out of the box, but multi-channel sync, multiple locations and purchase orders usually need more. I've worked on a live WooCommerce store through a design revamp, plugin replacements and an upgrade from PHP 7.4 to PHP 8.4 on Artic Flex, so I understand how carefully store data needs to be handled.
Common mistakes
Syncing in both directions without rules. Systems overwrite each other. One source of truth is essential.
No movement history. Without it, you can't find where stock went.
Ignoring failed syncs. A silent failure means overselling. Alerts are essential.
Too much complexity on day one. Start with accurate stock levels and alerts, then add purchasing and reports.
Skipping staff training. Inventory accuracy depends on people recording movements correctly.
Process before software
The 20% reduction in stockouts I mentioned didn't come from software alone. It came from agreeing simple rules: who records stock coming in, when counts happen, what the reorder points are and who gets alerted. The system made those rules easy to follow. Before building anything, I'll walk through your process with you and suggest small changes that make the system work better from day one.
Starting small
You don't need every feature at once. A common first version is accurate stock levels with a movement history, low-stock alerts and sync with your online store. Once your team trusts the numbers, purchase orders, multiple locations and detailed reports can follow.
What it usually costs
Integrating existing systems depends on their APIs. A focused custom system with products, movements, alerts and website sync is a sensible first version. You'll get a fixed quote after we talk.
How we'd work
- We talk about where you sell and how stock is tracked today.
- I map your process and recommend integration or a custom system.
- You get a quote with timeline and fixed price.
- I build with preview links.
- We import current stock and test with real orders.
- We launch, and I train your team.
Let's get your stock under control
Tell me how and where you sell. I'll reply with a plan and a fixed quote.
