Data silos between platforms
Customer data lives in your CRM, financial data in your ERP, orders in your e-commerce platform. No single source of truth exists, and teams spend hours reconciling conflicting records.
API Development & Integration.
We design versioned APIs, build secure system-to-system integrations, and implement monitoring layers that detect the moment data falls out of sync.
The cost of disconnected systems.
Data silos, manual re-entry, and brittle integrations create operational drag that compounds with every new tool your team adopts.
Manual data re-entry across tools
Staff copy-paste records from one system to another. Each manual transfer introduces latency, formatting mismatches, and the risk of transposition errors that cascade downstream.
Brittle point-to-point integrations
Direct connections between systems break when either side changes a field name, adds a required parameter, or updates an authentication method. Each fix is reactive and expensive.
No visibility when systems fall out of sync
When a webhook fails or a sync job silently drops records, nobody knows until a customer complains or a report shows incorrect numbers. There is no alerting layer in place.
Enterprise-grade APIs. Built to last.
Every API we build follows five core principles: documented contracts, semantic versioning, security by default, full observability, and resilient error handling.
Custom REST APIs
Documented, versioned APIs designed around your domain. Clean endpoint structures, consistent error handling, and OpenAPI specs generated automatically.
- OpenAPI 3.0 specs
- Semantic versioning
- Consistent error responses
- Auto-generated docs
Webhook infrastructure
Event-driven notifications with retry logic, signature verification, and delivery tracking. Your systems react to changes in real time instead of polling.
- Retry with backoff
- HMAC signature verification
- Delivery tracking
- Event filtering
Real-time data sync
Bidirectional synchronization between your CRM, ERP, and operational platforms. Conflict resolution rules handle concurrent updates gracefully.
- Bidirectional sync
- Conflict resolution
- Change data capture
- Real-time streaming
Authentication & authorization
OAuth 2.0 flows, JWT validation, API key management, and role-based access control. Every endpoint protected by default.
- OAuth 2.0 with PKCE
- JWT validation
- API key management
- Role-based access control
API gateway management
Rate limiting, request routing, load balancing, and caching layers. A single entry point that manages traffic across all your microservices.
- Rate limiting
- Request routing
- Load balancing
- Response caching
Integration testing & monitoring
Automated contract tests, load tests, and synthetic monitoring. Catch breaking changes before they reach production.
- Contract testing
- Load testing
- Synthetic monitoring
- Alerting on degradation
From API design to production reliably.
Every integration follows the same structured process. Documented contracts first, then iterative development with automated testing at every step.
Phase 1
API design & documentation
We map your integration requirements, define endpoint contracts, and produce OpenAPI specifications. Every payload, error response, and authentication flow is documented before development begins.
- OpenAPI specification
- Integration requirements doc
- Authentication flow diagrams
- Data model mapping
Phase 2
Development & testing
Iterative API development with automated contract testing at every step. Endpoints are built, validated against specifications, and load-tested with production-scale traffic patterns.
- Working API endpoints
- Contract test suite
- Load test results
- SDK generation
Phase 3
Integration & security
Connect your systems through the API layer. Authentication flows, rate limiting, and monitoring are configured. End-to-end integration tests verify data flows correctly across every platform.
- System integrations
- Security configuration
- End-to-end test suite
- Performance benchmarks
Phase 4
Deploy & monitor
Staged deployment with monitoring dashboards, alerting rules, and runbooks. Your team has full visibility into every request, error, and performance metric from day one.
- Production deployment
- Monitoring dashboard
- Alerting configuration
- Runbook documentation
Connects to the platforms your business runs on.
We build APIs and integrations for the tools your team already uses. No migration required.
Salesforce- SAP
- NetSuite
Shopify
Stripe
HubSpot
Slack
QuickBooks- Workday
ServiceNow- Zendesk
Twilio
AWS
Google Cloud
Azure
Jira- GitHub
- Datadog
And 200+ more platforms via custom REST and GraphQL connectors.
Our systems were held together with manual CSV imports and prayer. Necsen designed a proper API layer that connected our CRM, billing, and warehouse systems. Data flows in real time now, and we haven’t had a sync failure in six months.
Common questions.
The questions we hear most before an engagement begins — scope, timelines, security, and how we work with your existing team.
REST is our default for simplicity, cacheability, and broad tooling support. We recommend GraphQL when reducing over-fetching significantly improves mobile performance or when your frontend team needs flexible query capabilities across complex data relationships.
Every API ships with an OpenAPI 3.0 specification generated directly from the codebase. This drives auto-generated documentation portals, client SDK generation, and contract test suites that validate the API matches its specification.
Tiered rate limiting: token bucket for general access, sliding window for authentication endpoints, and fixed window with burst allowance for webhooks. Limits are configurable per client and monitored in real time.
Every API follows the OWASP API Security Top 10. Authentication uses OAuth 2.0 with PKCE for public clients, API keys with HMAC signing for server-to-server, and mTLS for environments with strict regulatory requirements.
URL-based semantic versioning (v1, v2) for major breaking changes, header-based versioning for minor additions. We maintain a six-month deprecation window with migration guides and automated consumer notifications.
Dashboards showing request volume, latency percentiles (p50/p95/p99), error rates, and upstream health. Alerts trigger on latency spikes, error threshold breaches, and certificate expiration. All included with every deployment.
Ready to connect your systems?
Tell us about your integration challenges. We review your integration landscape and provide a fixed-scope proposal within 48 hours.
No commitment. No pitch deck. Just a technical conversation.
Integration guides.
Where the off-the-shelf connectors stop, written up from live work.
Zapier vs Make vs n8n
Three automation platforms with genuinely different economics and failure modes. Where each one stops, and which shape of business each actually suits.
Read the comparisonQuickBooks & Shopify
Why stock QuickBooks–Shopify connectors break on inventory, payouts and sales tax — and what a reconciled integration actually has to handle.
Read the guideQuickBooks & Stripe
Stripe deposits net of fees in batched payouts. Here is what that does to your books, and what a QuickBooks integration has to handle to reconcile cleanly.
Read the guideSalesforce & QuickBooks
Connecting Salesforce to QuickBooks is an object-mapping problem before it is a technical one. Here is what has to be decided, and where connectors fall down.
Read the guideHubSpot & Salesforce
Running HubSpot and Salesforce together means deciding what each one owns. Where bidirectional sync goes wrong, and how to keep both systems trustworthy.
Read the guideHubSpot & QuickBooks
Getting deals into QuickBooks and payment status back into HubSpot — where the marketplace app stops, and what changes if you are on Desktop.
Read the guideTwilio & Salesforce
SMS and WhatsApp from Salesforce sounds simple until consent, opt-out and delivery status have to live on the record. What the build actually involves.
Read the guide