Best API Integration Development PartnerDevelopment Partner
We build custom API integrations that connect your tools and data. Over 200 integrations shipped for clients in 50+ countries.
IRPR is your best API integration development partner for connecting SaaS tools, internal systems, and third-party data sources. We build integrations using REST, GraphQL, WebSockets, and protocol buffers, with strong error handling and retry logic. Our senior engineers have integrated with over 100 APIs including Stripe, Salesforce, HubSpot, Twilio, and Slack.
Every integration project ships in 8 to 12 weeks with a fixed price between $80,000 and $250,000 depending on complexity. We handle authentication (OAuth, API keys, JWT), rate limiting, data mapping, and real-time sync. All integrations include monitoring and alerting via Datadog or Sentry out of the box.
Our clients are CTOs who need to connect their product to 5+ external APIs, VPs of Engineering who want a reliable sync between Salesforce and a custom platform, and product managers at growth-stage startups who need ecommerce integrations with Shopify, Stripe, and QuickBooks. We also work with healthcare compliance officers requiring HIPAA-compliant API connections.
Types of software we ship.
Salesforce API Integration
Sync leads, opportunities, and custom objects between Salesforce and your app. Uses Bulk API v2 for high volume.
Stripe Payment Integration
Connect Stripe for subscription billing, invoicing, and payout reconciliation with webhooks and 3D Secure.
HubSpot CRM Integration
Two-way sync of contacts, deals, and activities using HubSpot's OAuth 2.0 and private apps endpoints.
Slack Bot & Webhook Integration
Build custom Slack bots and slash commands that interact with your backend via Socket Mode and Events API.
Twilio SMS & Voice Integration
Send programmable SMS, make calls, and handle inbound messaging using Twilio's REST API and StatusCallbacks.
Shopify Store Integration
Sync products, inventory, orders, and customers from Shopify to your ERP or warehouse system using GraphQL Admin API.
QuickBooks Accounting Integration
Pull invoices, bills, and journal entries from QuickBooks Online using OAuth 2.0 and Idempotency keys.
Zapier / Make Integration Bridge
Create custom Zapier or Make (Integromat) integrations that connect niche APIs not available in public libraries.
We build for every business type.
SaaS Platforms
Financial Services
Healthcare
Ecommerce and Retail
Enterprise Systems
Why IRPR is the Best API Integration Development Partner
We have shipped over 200 integrations with 99.9% uptime and an average timeline of 12 weeks.
Our team of senior engineers has deep experience with API design patterns, rate limiting, caching strategies, and error handling. Every integration includes thorough logging and monitoring so you can see exactly what data flows when. We use tools like Redis for caching and Bull for queuing to handle spikes without data loss.
We guarantee a fixed price after a 2-week Roadmap phase. No hourly billing. No surprise costs. You know the exact timeline and cost before we write production code. Our clients report 40% faster integration times compared to previous agencies, and all source code is delivered with full ownership.
The Difference Between a Generic Dev Shop and Your Best API Integration Partner
Most agencies deliver fragile integrations that break when APIs change. IRPR builds integrations that last.
Generic dev shops often assign junior developers who learn on your dime. They write point-to-point code with no retry logic or monitoring. When a third-party API removes a field, your integration silently fails. You only find out when the CEO asks why the dashboard is empty.
IRPR assigns senior engineers who have built integrations for Stripe, Salesforce, Slack, Twilio, and 100+ other APIs. We use circuit breakers, exponential backoff, and idempotency keys to handle failures gracefully. Every integration is covered by automated end-to-end tests that run on every deploy.
- Junior developers with 2-3 years experience
- No circuit breaker or retry logic
- No monitoring – silent failures
- Hourly billing with scope creep
- No ownership – you sign away IP
- 1-2 week response time on bugs
- Senior engineers with 8+ years API experience
- Circuit breakers, exponential backoff, idempotency
- Datadog/Sentry monitoring and alerting
- Fixed price after 2-week Roadmap
- You own all source code and IP
- Same-day response for production issues
How We Build Your API Integration: A Proven 4-Step Process
Every integration follows our Idea-to-Release framework with clear milestones and deliverables.
We start with a Roadmap phase where we map every endpoint, field, and authentication requirement. You get a detailed integration specification with data flow diagrams and timeline. No guesswork.
Then we build the integration in iterative sprints, testing each endpoint against real sandbox environments. The final step is a controlled release with canary deploys and rollback plan.
Every Integration Ships with These Deliverables
You get production-ready code, monitoring, and documentation from day one.
We believe in shipping more than code. Every integration comes with a fully documented API contract, postman collection, and a runbook for on-call engineers. Your team can take over immediately.
All code is delivered in your private GitHub repository with a pre-configured CI/CD pipeline. We also set up error tracking in Sentry and performance monitoring in Datadog before the first deploy.
- Source code in your private GitHub repo
- CI/CD pipeline with GitHub Actions
- Postman collection with all endpoint examples
- Data flow diagrams (LucidChart or Miro)
- Sentry error tracking with alerts
- Datadog integration dashboards
- Runbook for incident response
- Automated end-to-end tests (Cypress, Jest)
- Full ownership of all code and IP
- 1 month free post-launch support
What we ship in this practice.
Two-Way Salesforce-HubSpot Sync
Built a real-time syncing integration between Salesforce and HubSpot for a 500-person sales team. Used Salesforce Bulk API v2 and HubSpot OAuth 2.0. Reduced duplicate data entry by 12 hours per week per rep. Tech stack: Node.js, PostgreSQL, Bull queue, Redis cache.
Stripe Subscription Sync to QuickBooks
Created an integration that pushes Stripe invoices and payouts into QuickBooks Online every hour. Handled chargebacks and refunds automatically. Saved the accounting team 20 hours per week. Tech stack: Python, Stripe API, QuickBooks OAuth 2.0, Airflow for scheduling.
Shopify-to-Warehouse Inventory Sync
Integrated Shopify with a custom warehouse management system using GraphQL Admin API. Pulled stock levels, orders, and returns every 5 minutes. Reduced overselling incidents by 95%. Tech stack: Ruby on Rails, Shopify GraphQL, Sidekiq, WebSockets.
Slack Bot for Jira Ticket Creation
Developed a Slack slash command that lets support agents create Jira tickets from Slack messages. Uses Slack Socket Mode and Jira Cloud REST API. Cut ticket creation time from 3 minutes to 10 seconds. Tech stack: Node.js, Express, Slack Bolt, Jira API.
HIPAA-Compliant EHR Data Exchange
Built a secure, audit-logged integration between a telehealth app and Epic EHR using FHIR R4 and SMART on FHIR. Handled patient demographics, appointments, and clinical notes. Passed HIPAA penetration test with zero findings. Tech stack: TypeScript, Express, FHIR SDK, PostgreSQL with encryption, AWS KMS.
Twilio SMS for Two-Factor Authentication
Integrated Twilio's Verify API into an enterprise login flow to add SMS-based MFA. Handled rate limits and retries with exponential backoff. Reduced account takeover incidents by 99.9%. Tech stack: Node.js, Twilio Verify, Redis, Terraform for deployment.
Why teams hire us.
Senior engineers only, no juniors
Every integration is designed and coded by an engineer with 8+ years of experience. We don't staff junior developers to reduce costs. Our team has built integrations for Stripe, Salesforce, Twilio, and 100+ other APIs.
Fixed price after 2-week Roadmap
We put a fixed price on your integration after we fully understand the scope. No hourly billing, no unexpected surcharges when an API changes. You approve the cost before we write a single line of production code.
Full code ownership and IP transfer
When we finish, you own every line of code, every test, and every configuration file. We don't lock you into a proprietary platform or require ongoing licensing fees. You can take the integration to any other engineer.
Production monitoring and alerting out of the box
We ship every integration with Datadog dashboards and Sentry error tracking. You know the moment an API rate limit is hit or a webhook fails. Our average time to detect an issue is under 2 minutes.
We handle API versioning and deprecation
When a third-party API deprecates a field or endpoint, we update your integration proactively. We monitor changelogs and use feature flags to roll out updates without breaking existing flows.
Global async team with same-day overlap
Our team works across 50+ countries but every client gets dedicated overlap with their timezone. We guarantee at least 4 hours of real-time collaboration per day. You can reach us on Slack during business hours.
Idea → Roadmap → Product → Release.
Every engagement runs through the same four-stage pipeline. Predictable by design.
Questions clients ask first.
Related services and industries.
Ready to build? Let's talk.
30-minute discovery call. No deck. We'll tell you honestly what it takes, how long, and how much.