API Integration Services & Custom API Development for Enterprise Systems
Vortex provides API integration services and custom API development for companies whose ERP, CRM and SaaS tools need to share data reliably. We build versioned REST and GraphQL APIs, event-driven integrations and connectors for platforms like Salesforce, HubSpot and Workday. We also build the SOAP, EDI and file-based links that older systems still depend on. Every integration is monitored, so a failed sync alerts an on-call engineer before a customer finds it. Most projects start with a two-week integration audit.
What Is API Integration?
API integration connects two or more systems through their APIs so data and actions move between them automatically: an order created in one system appears in another, or a status change triggers work somewhere else. Data can move as real-time requests, as events when something changes, in scheduled batches, or as files dropped in a shared location. For the basics, and how integrating an API differs from building one, read what API integration is.
API Integration Services We Provide
Our API integration services cover modern APIs, bespoke system connections, enterprise platforms, event-driven architecture and the legacy interfaces that still carry critical business workflows.
Integration Architecture
We map what exists, define the boundaries that should exist, and sequence the move. Point-to-point connections are fine where volume is low and the contract is stable. When many systems care about the same change, we put an event backbone in, and access that needs governance goes behind an API gateway.
Enterprise System Integration
We connect SAP, Oracle, Dynamics 365, Salesforce, NetSuite, Workday, ServiceNow and HubSpot, along with whatever industry-specific systems came with an acquisition. For commerce teams, that includes order, inventory and warehouse flows, such as an order management system feeding a warehouse. If the storefront itself needs work, see our ecommerce development services.
Event-Driven Architecture
Where systems should react to change instead of polling for it, we use Kafka, RabbitMQ or cloud-native messaging. We include the parts people skip: idempotency, ordering, replay and dead-letter handling.
Legacy and File-Based Integration
SOAP, EDI, SFTP, fixed-width files and mainframe interfaces still carry a lot of critical business workflows. On a modernization program they are often the actual blocker, so we treat them as first-class integration work.
API Security and Access Control
Security is the first thing to check in any API development company. We authenticate and rate-limit every API we build per client, so one consumer can't degrade the platform. We use OAuth 2.0, OIDC, SAML, mTLS and API keys with rotation, and put access behind a gateway (Kong, AWS API Gateway, Azure API Management or Apigee) where it needs governance. For the wider security program, see Security & Compliance.
Monitoring
Every integration is instrumented for success rate, latency and volume anomalies. Alerts go to an on-call engineer, so a failed sync gets handled before a customer reports it.
API Development Services
When the API is the thing being built, our API development services cover design, documentation and the controls around it.
API Design and Development
We build REST, GraphQL, gRPC and event-stream APIs. Each one is versioned, so a change doesn't break an existing consumer, and documented in OpenAPI or AsyncAPI so a partner can integrate without needing a call. Rate limits and authentication stop any one client from degrading the platform.
Partner and Public APIs
When your API is a product, it needs developer documentation, sandbox environments, key management, usage analytics and a versioning policy. Outside developers judge it mostly on the docs, the sandbox and how predictable the versioning is.
APIs for SaaS Products
Multi-tenant products need an integration surface their enterprise customers can build on: REST APIs and webhooks that are versioned, documented and rate-limited. Our SaaS development company team designs that surface with the platform.
How Integration Debt Accumulates
Releases slow down and data drifts out of sync without anyone noticing. Customers find the failures first. Usually there is also one person who understands how it all fits together, and their departure would be an incident.
Each integration is reasonable on its own. The CRM needs order data, so a nightly job pushes it. Finance needs invoices, so a script pulls them. A partner needs inventory, so someone opens an endpoint.
Over time, point-to-point integrations pile up across CRM, finance, partners, operations and internal systems. Authentication patterns drift apart, monitoring becomes inconsistent, and a change to one system means auditing every connection around it.
Custom Integration or an iPaaS Platform?
Sometimes a platform beats custom code, and we will say so. We work with MuleSoft, Boomi, Workato, Zapier, Make and n8n as well as building custom API integration, and we cost out both options for you. The deciding number is usually your expected volume five years out.
| iPaaS platform fits | Custom integration fits | |
|---|---|---|
| Connectors | Ready-made connectors exist for your systems | Systems are legacy, niche, or have no usable API |
| Volume | Moderate | High |
| Latency | Latency is not critical | Latency matters |
| Transformation | Simple field mapping | Complex logic, ordering or replay requirements |
| Maintenance | Your team will maintain it in a low-code tool | Your team or ours maintains code, docs and monitoring |
| Cost over time | License cost stays below engineering cost | License cost outgrows engineering cost |
API integration solutions can also mix the two: iPaaS for standard SaaS-to-SaaS syncs, custom services for the high-volume or legacy paths.
- 200+ systems in production
- Production systems since 2022
- US-based engineers
- One accountable team from audit to operations
Integration work in production: for Chicago Detours we built the booking system and listing integrations behind a rebuilt website. The case study reports bookings up 50%.
How an API Integration Project Runs
Integration audit · 2 weeks
We map, risk-rank and sequence every integration, and flag the ones most likely to fail first.
Integration architecture
For each flow we decide how the data should move (request and response, events, scheduled batches or files) and whether it belongs point-to-point, on an event backbone or behind a gateway.
Build with monitoring
Connectors, APIs and event flows ship with success-rate, latency and volume monitoring from the first release.
Dual-run cutover
Systems that can't go offline get a new path running alongside the old one while we compare outputs. Traffic shifts by percentage once the data agrees, and the old path stays live until it is provably unnecessary.
Handover or managed operation
Everything is documented and monitored so your team can take it over, or we operate it under a managed agreement.
Technology Stack
Our API development and integration services run on proven protocols, messaging systems, gateways and authentication standards.
- Protocols
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- REST
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GraphQL
- gRPC
- SOAP
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WebSockets
- webhooks
- EDI
- Messaging
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Kafka
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RabbitMQ
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AWS SQS/SNS/EventBridge
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Azure Service Bus
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Google Pub/Sub
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- Gateways
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Kong
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AWS API Gateway
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Azure API Management
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Apigee
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- iPaaS
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MuleSoft
- Boomi
- Workato
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Zapier
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Make
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n8n
Where a platform beats custom code.
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- Auth
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- OAuth 2.0
- OIDC
- SAML
- mTLS
- API keys with rotation
- Docs
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OpenAPI
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AsyncAPI
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Postman
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The messaging and gateway layers run on your cloud. If that infrastructure needs work too, see our DevOps consulting services.
Frequently Asked Questions
Get a range for your integration
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Start With an Integration Audit
In two weeks we map, risk-rank and sequence every integration you run, and flag the ones most likely to fail first.
