API integration services that keep your systems in sync
When orders live on a marketplace, stock lives in a spreadsheet, invoices live in your accounting tool and tracking numbers live in yet another dashboard, someone on your team spends part of every day moving data around. Weras Labs builds integrations between marketplaces, payment gateways, shipping, invoicing and ERP systems that run reliably and tell you when something goes wrong instead of failing silently.
Integrations we build
Most integration work falls into a handful of categories:
- Marketplace integration: syncing products, prices and stock to marketplaces such as Amazon, Etsy, eBay or regional platforms, and pulling every order into one place.
- Payment gateway integration: Stripe and other gateways for one-off payments, subscriptions, refunds and strong customer authentication.
- Shipping integration: creating shipments, printing labels and sending tracking links to customers automatically.
- Invoicing and accounting: issuing invoices from completed orders and keeping your accounting software up to date.
- ERP and CRM connections: keeping customers, products and orders consistent between your ERP, CRM and online store.
- Custom APIs: a secure, documented API that opens your own system to partners, resellers or your mobile app.
We can add an integration to your existing website or software, or build it as a separate middleware service that orchestrates the whole flow.
What makes an integration reliable
Connecting to an API is usually the easy part. Keeping that connection healthy for months is the real work: third-party services slow down, endpoints time out, webhooks arrive twice or out of order. We design for those cases from day one:
- A queue that retries failed requests with sensible back-off
- Idempotency checks so the same order is never processed twice
- Webhooks for real-time events, with scheduled sync as a fallback
- Logging of every operation and immediate alerts when something fails
- Secure storage of API keys and least-privilege access
That way you learn about a problem from the system itself, not from an unhappy customer.
What affects the cost
The price of an integration depends less on the brand name of the service and more on the details of the job:
- How many services need to be connected, and how good their documentation is
- One-way or two-way synchronization
- How complex the mapping of products, variants and categories is
- Real-time behaviour versus scheduled syncs
- Whether you need an admin panel, reporting or an error review screen
We send a free quote after a short conversation about your setup. Scope can range from a single marketplace connection to a full multi-channel sales backbone, built in phases if that suits your budget.
Timeline and technology
An integration with a single, well-documented service typically goes live in 1–3 weeks. Projects that combine several marketplaces, shipping and invoicing in one flow usually take 4–10 weeks.
We write integrations in Node.js and TypeScript, backed by queues and scheduled jobs. Data is stored in Firebase or another cloud database that fits the project, and admin panels are built with Next.js and deployed on Vercel. We work with REST, GraphQL, SOAP and webhook-based services, including older XML endpoints that still power many business systems.
Why Weras Labs
Weras Labs is a small, senior software team led by founder Habip Dayan. Our own products run on payment gateways, licensing systems and third-party APIs every day, so we know how integrations behave once real traffic hits them.
You talk directly to the developer who builds your integration, so when something needs attention you know exactly who will look at it. We are based in Turkey and work with clients across Europe and beyond, remotely and in English.
What's included
Marketplace sync
Product, price and stock changes reach every sales channel automatically.
Unified order list
Orders from all channels land in one place, ready to fulfil.
Shipping labels and tracking
Shipments are created and tracking links sent without manual steps.
Payment gateways
Stripe and other gateways for payments, subscriptions and refunds.
Automatic invoicing
Completed orders generate invoices in your accounting or invoicing system.
Webhooks and queues
Real-time events are processed and failed calls are retried safely.
Monitoring and alerts
Every call is logged and you are notified the moment something breaks.
Your own API
A documented, secure API for partners, resellers and your own apps.
How we work
- 1
Discovery
We map the systems you use, how data should flow and where it breaks today.
- 2
Technical review and quote
We review the relevant API documentation and send a written scope, timeline and cost.
- 3
Build in a sandbox
The integration runs first in a test environment with realistic scenarios.
- 4
Gradual rollout
We start with a subset of products or orders, then switch everything over.
- 5
Maintenance
When providers change their APIs, we keep your integration up to date.
Frequently asked questions
Can you integrate several marketplaces at once?
Yes. We can manage products, stock and prices from a single source and push them to every marketplace, while collecting all orders in one place. New channels can be added to the same foundation later.
Why choose a custom integration over an off-the-shelf connector?
Ready-made connectors work well for standard setups. If your product mapping, business rules or systems are unusual, a custom integration means fewer manual fixes and fewer errors.
How long does a Stripe or payment gateway integration take?
Adding a standard checkout flow to an existing site usually takes 1–2 weeks. Subscriptions, marketplace payouts or complex refund rules can extend that.
Do you work with webhooks?
Yes. We use webhooks wherever a service offers them, verify their signatures, handle duplicates and keep a scheduled sync as a safety net.
Can you connect to our ERP system?
If your ERP exposes an API, a web service or database access, usually yes. We review the available connection options during the first call and give you a clear answer.
How is the price of an API integration calculated?
It depends on the number of services, whether sync is one-way or two-way and how complex the data mapping is. We send a free quote after understanding your setup.
Related services
- E-commerce DevelopmentFast, conversion-focused online stores you own, with payments, shipping, invoicing and marketplace sync built in.
- Invoicing SoftwareCustom invoicing software that brings quotes, invoices, recurring billing and payments together, with e-invoicing integration.
- Inventory Management SoftwareCustom, barcode-ready, web-based inventory software: warehouses, branches and online store stock in one place.
- Business Process AutomationCustom automation that removes repetitive manual work: spreadsheet reports, data entry and syncing between the tools you already use.
Let's talk about your project
Describe what you need in a few sentences. We'll pin down the scope together and send a free quote within one business day. You talk directly to the developer.