# Custom API Integration > We connect your applications through secure APIs: CRM, ERP, payments, email, SMS or marketplaces. Webhooks, OAuth2, complete API documentation. - Source: https://maxdev.ro/en/services/api-integration/ - Romanian version: https://maxdev.ro/servicii/integrare-api/ - Site index for AI: https://maxdev.ro/llms.txt --- **Your systems, connected through an API that actually works.** We build REST integrations and custom APIs between your applications: CRM, ERP, payments, email, SMS or marketplaces, with secure authentication and data flowing automatically, in both directions. From a single targeted integration to your own API, exposed for your partners. ## Any two systems can talk to each other. Maybe you have two applications that don't communicate at all. Maybe you receive data manually, through export-import. Maybe you want to expose your own API for partners. In every case, we build the connection to fit your exact need, not a generic solution. **Integration between two existing systems** We connect two applications that don't communicate natively (e.g. a CRM and an online store), through a custom REST API written specifically for your flow. **Webhooks & real-time events** We set up webhooks that trigger actions instantly when something happens in a system: a new order, a confirmed payment, a status change. **OAuth2 authentication & API keys** We implement secure authentication (OAuth2, JWT, rotating API keys), with no hardcoded keys or unprotected access to your data. **[Payment processor integration](https://maxdev.ro/en/services/ecommerce-integrations/payment-processors/)** We connect your store or app to payment processors through their APIs, with correct handling of confirmation webhooks. **Email & SMS integration** We send transactional notifications (confirmations, alerts) through email and SMS APIs, wired directly into the application flow. **CRM integration** We sync customers, leads, and activity between your site or app and the CRM your sales team uses. **Marketplace integration** [We connect your store to eMAG's API and other marketplaces](https://maxdev.ro/en/services/online-store-development/), for product, stock, and order sync. **Your own API, exposed for partners** We build a documented API, with authentication and rate limiting, that your partners can consume directly. **Complete API documentation** We deliver clear documentation (endpoints, request and response examples), so your team or partners can integrate quickly. **Data migration between systems via API** We transfer historical data (customers, orders, products) between two systems, through a script that uses both APIs. **Monitoring & error handling for integrations** Logs, automatic retries, and alerts when an integration fails, so you don't lose data without knowing. **ERP integration through a custom API** We connect your app to the ERP where no ready-made connector exists, with bidirectional sync. ## What an API integration built by us includes. We don't connect two systems at random. Every integration is designed, secured, and monitored, so data keeps flowing correctly long term. API ANALYSIS & DESIGN ### Architecture comes before code. We analyze the systems that need to be connected, what data flows and how often, then design the integration architecture before writing the first line of code. Field mapping between the two systems' data A clear decision: real-time webhook or fixed-interval polling A fallback plan if one of the systems is unavailable AUTHENTICATION & SECURITY ### Access limited to exactly what's needed. We use OAuth2, rotating API keys, or JWT, with permissions restricted to the integration's data, not universal keys with full system access. Encrypted connections and rotating API keys, never hardcoded Separate permissions per integration, not global access Rate limiting, to prevent abuse or overload SYNC & WEBHOOKS ### Data that flows automatically, in both directions. We configure real-time sync where possible (webhooks) or at a clearly defined interval (polling), with automatic retry on failure. Webhooks for instant events, with no delay Scheduled polling where webhooks aren't available Automatic retry with backoff, so a temporary error doesn't lose data MONITORING & DOCUMENTATION ### The integration stays maintainable after delivery. We deliver logs, failure alerts, and complete documentation, so the integration can be understood and adjusted by another technical team, not just by us. Detailed logs for every request and response Automatic alerts when an integration fails repeatedly Complete documentation: endpoints, authentication, examples ## Exactly what we sell, shown with real systems. Every integration below is an example of systems we can connect through a custom API, with data flowing automatically, in both directions. CRM & internal systems **Internal systems** We connect your app to your CRM, ERP, or accounting software, without manual export-import between systems. ![Oblio](https://maxdev.ro/assets/oblio.webp) **Invoicing** Invoices generated automatically through the API, on every relevant event. Couriers **Delivery** [AWB generated automatically and tracking synced, straight through the courier's API](https://maxdev.ro/en/services/ecommerce-integrations/couriers/). ![Stripe](https://maxdev.ro/assets/stripe.svg) **Payments** Payment confirmations processed automatically through webhooks, no manual checking in the dashboard. eMAG & marketplaces **Marketplaces** Product, stock, and order sync between your store and external marketplaces. Email & SMS **Notifications** Transactional notifications sent automatically through the API, wired directly into the application flow. **What happens during a data sync through a custom API** From an event in one system to updated data in the other, everything flows automatically, with no manual work. Event triggered Something changes in system A Webhook sent Instant notification to our API Data validated Checked and mapped to fields Data written Updated in system B Confirmation & log Result recorded for audit ## Companies that chose us as their technology partner. Some of the companies we've built API integrations between systems for. [Forelit](https://b2b.forelit.ro) [Hemerama](https://hemerama.com) [Somnexpert](https://somnexpert.ro) [Modularbox](https://modularbox.ro) [Electrocamelite](https://electrocamelite.ro) [Pigeonshop](https://pigeonshop.ro) [Rinostore](https://rinostore.ro) [Irigarden](https://irigarden.ro) [Travandi](https://travandi.ro) [Somnart](https://somnart.ro) ## Questions we get asked often. ### Can you integrate any two systems, even if one doesn't have a public API? In most cases, yes. If a system doesn't expose a public API, we look for alternatives: automated export, database-level integration, or an unofficial API documented by the community, depending on what the platform allows. ### What's the difference between a REST API and a webhook? With a REST API, your application actively requests data from another system, whenever you need it. With a webhook, the other system automatically sends you a notification when something happens, without you having to keep asking. ### How long does an API integration take? A simple integration, with clear API documentation on both sides, can be ready in one to two weeks. A complex integration, with data mapping and business logic, usually takes three to six weeks. ### How do you keep data safe during an integration? We use secure authentication (OAuth2, rotating API keys), encrypted connections, and access limited to exactly the data the integration needs, not the entire system. ### Can you build our own API for our partners to use? Yes. We build a documented API, with its own authentication and rate limiting, that your partners can consume directly, without giving them access to your internal system. ### What happens if an external API changes or goes down temporarily? We build integrations with error handling and automatic retries, so a temporary failure doesn't mean lost data. If the provider changes the API's structure, we adjust the integration to the new version. ### Do you also integrate with specific ERPs, like SoftOne? Yes, ERP integration also has its own [dedicated page](https://maxdev.ro/en/services/erp-integration/), because it's a specific case we run into often. Here we treat API integration as a general technical discipline, with the ERP being just one of the systems we can connect. --- ## Contact - Phone: +40 735 343 355 - Email: contact@maxdev.ro - WhatsApp: https://wa.me/40735343355 - Book a call: https://cal.com/daniel.maxdev - Address: 66A Theodor Pallady Blvd, District 3, Bucharest, Romania