System Integration & APIs
Separate systems made to work as one, without becoming a black box.
Overview
Most businesses run several systems that were never designed to talk to each other: a legacy CBS, a modern web platform, a payment gateway, an ERP, each holding a piece of the truth that has to be manually reconciled by someone copying numbers between screens. XETUP builds the integration layer that closes that gap, whether that means a clean new API or a bridge into a decades-old system nobody else wants to touch.
This is the same discipline behind SIRECONS, where reconciliation and settlement pipelines have to be correct to the transaction, connecting core banking systems, payment rails, and internal platforms without losing a single record in the handoff.
What's Included
- Custom API design and development, RESTful or GraphQL depending on the need
- Third-party and payment gateway integrations, including local and international rails
- Legacy system modernization and bridging into modern platforms
- B2B and EDI-style data exchange between business partners
- Webhook and event-driven pipelines for real-time system-to-system updates
- Integration monitoring and error handling so a failure is caught immediately
Built For
- Businesses whose internal systems don't talk to each other
- Companies integrating a payment gateway into their platform for the first time
- Enterprises connecting a legacy system to a modern platform without a full rebuild
- Banks and fintechs needing settlement or reconciliation pipelines that must be exact
- Retailers syncing inventory and orders across multiple sales channels
- SaaS companies opening their platform to partner and third-party integrations
- Organizations replacing manual data entry between disconnected systems
How We Actually Work
Named practices, not marketing language. This is the specific methodology applied to this service line, described as what it is, not as a certification XETUP does not hold.
API-First Design
APIs are designed and documented against OpenAPI/REST or GraphQL standards before implementation begins, so integration partners have a stable contract to build against.
Event-Driven Architecture
Systems communicate through events and webhooks rather than constant polling, which keeps data current in near real time without hammering either system with unnecessary requests.
Idempotent Integration Patterns
Every integration is designed so a retried or duplicated request can never double-process a transaction, the core discipline behind financial and inventory data that has to reconcile exactly.
Payment Gateway Reconciliation
Payment integrations are built with a reconciliation layer that matches every transaction against the gateway's own record, catching discrepancies instead of trusting a single source blindly.
Legacy System Modernization
Older systems are bridged through an integration layer rather than force-migrated overnight, letting a business modernize incrementally without a risky big-bang cutover.
Reasons Teams Choose Us for This
No black-box integrations
The same engineers who build the core system design its integrations, so nothing is a mystery vendor-built bridge nobody internally understands.
Reconciliation-safe by default
Idempotent, reconciliation-aware patterns are standard for any integration touching financial or inventory data, not an extra feature that has to be requested.
Comfortable with legacy systems others avoid
Bridging into an undocumented legacy system is treated as a normal part of the work, not a reason to decline the engagement.
Failures are caught immediately
Monitoring is built into every integration, so a broken connection is flagged the moment it happens, not discovered a week later during reconciliation.
Questions About This Service
Modern APIs, legacy core systems, payment gateways, ERPs, and internal platforms across REST, GraphQL, SOAP, or file-based exchange. Scope is assessed based on what the systems actually expose.
Undocumented and legacy systems are audited directly, including database-level or file-export integration where no clean API exists. This kind of bridge work is a normal part of the practice, not an edge case.
Idempotent design, retry logic, and reconciliation checks are standard, with monitoring and alerting so a failed integration is flagged immediately rather than discovered during a manual audit.
Scoped to the specific systems and data involved. A single payment gateway integration might take one to two weeks; a multi-system reconciliation pipeline like a banking settlement system takes considerably longer.
Yes, this is core to engagements like SIRECONS, where integration accuracy is held to a banking-grade bar: every transaction reconciled, every discrepancy flagged, nothing silently dropped.
Tell us about your project
We'll respond with a concrete plan, not a sales pitch, within hours.