API Integration Services That Keep Your Systems in Sync

API integration services are what you need when copy and paste has become a job. Orders get rekeyed from Shopify into an ERP, new leads get exported from a form tool into HubSpot, and invoices get typed into QuickBooks by hand. Every manual step is slow, and every one is a chance to get a number wrong.

A well-built integration moves that data automatically, checks it, and tells someone when something fails. We provide API development and integration services as part of our web application development work, for ecommerce brands, SaaS companies and service businesses whose tools do not talk to each other out of the box.

What Is API Integration?

API integration is the connection of two or more software systems through their APIs (application programming interfaces) so they exchange data and trigger actions without a person in the middle. When an order is paid in Shopify, an integration can create the invoice in QuickBooks, update the customer in HubSpot and send the shipment to your warehouse, all within seconds.

REST, GraphQL, SOAP and Webhooks

Most modern platforms expose REST APIs that exchange JSON. Shopify also offers GraphQL, where you request exactly the fields you need. Older ERP and finance systems often still use SOAP with XML. Webhooks work the other way round: the platform calls your endpoint the moment something happens, which is faster and cheaper than polling every few minutes.

Public, Partner and Internal APIs

Public (open) APIs, such as Shopify's or Stripe's, are documented for any developer with an account. Partner APIs are opened only to approved companies, which is common with 3PLs, marketplaces and some ERPs, so access requests can add weeks to a timeline. Internal APIs connect your own systems to each other. Knowing which kind you are dealing with early tells us how much documentation and sandbox access to expect.

API Integration vs API Management

API integration is the work of connecting systems so data moves between them. API management is the governance of APIs you publish: gateways, keys, usage limits, analytics and developer portals, usually with tools such as Kong, Apigee or Azure API Management. Most small and mid-sized businesses need integration first. Management becomes relevant when you publish an API for partners or customers.

Our API Integration Services

• Ecommerce platforms. Shopify, WooCommerce, BigCommerce and marketplaces, syncing orders, products, stock and customers with your ERP, warehouse or accounting system.
• Payments and billing. Stripe and PayPal for checkout, subscriptions, refunds and payouts, with webhook handling that keeps your records matched to the payment provider.
• CRM and sales tools. HubSpot, Salesforce and Pipedrive, with deduplication rules so the same contact is not created twice from two sources.
• Accounting. QuickBooks Online and Xero, posting invoices, payments and fees with the right accounts and tax codes.
• Marketing and ad platforms. Google Ads, Meta Marketing API, GA4 and Klaviyo, including offline conversion uploads. For browser and server event tracking, see our server-side tracking service.
• AI model APIs. OpenAI, Anthropic Claude, Google Gemini, DeepSeek and Groq, with fallbacks between providers and cost controls.
• Custom APIs for your own systems. Documented REST APIs so partners, apps or a customer portal can read and write your data safely, usually built in Laravel by our PHP development team.
• Reporting pipelines. Scheduled data pulls into a reporting database that feeds custom dashboards.

How We Deliver API Integration Services

1. Map the data flow (2 to 4 days). We document which system is the source of truth for each field, which direction data moves, how often, and what should happen on conflict. This one page prevents most integration bugs.
2. Check each API's limits (2 to 3 days). We read the documentation and test with sandbox accounts: authentication method, rate limits, webhook support, pagination and version policy. Surprises found here cost hours, not weeks.
3. Build with failure in mind (1 to 3 weeks per flow). Every call is logged, retried with backoff when it fails temporarily, and parked in a queue for review when it fails permanently. Nothing disappears silently.
4. Test with real edge cases (about 1 week). Refunds, partial shipments, deleted records, special characters and time zones get tested on staging, not discovered in production.
5. Launch with monitoring (1 to 2 days, then 2 weeks of close watching). Alerts fire on repeated failures, and a simple status screen shows what synced and what did not. You get documentation for each flow and the credentials live in your accounts.

API Integration Deliverables and Signs of a Healthy Sync

Each integration project ends with outputs you can inspect, not just a promise that "it syncs":

• A data flow map per integration: systems, fields, direction, frequency, source of truth and conflict rules.
• The integration code in your repository, or the workflow in your own n8n, Make or Zapier account, with credentials stored in your accounts.
• A sync log and status screen that shows each record processed, failed or waiting for review.
• Alert rules that notify a named person by email or Slack when failures repeat.
• A runbook that explains how to replay a failed record, rotate a credential and upgrade an API version.

A healthy integration is measurable. Record counts match between systems at each reconciliation run, failed records are reviewed and cleared within an agreed time, no duplicates appear after webhook retries, and the API versions in use are still supported by each vendor. We check these together at handover and, on a retainer, every month.

API Integration Use Cases by Business Function

• Multi-channel order sync. Orders from Shopify, Amazon, eBay and a wholesale portal flow into one order system, with stock levels pushed back to every channel so you stop overselling.
• ERP and finance. Sales, refunds, payouts and fees post to QuickBooks Online, Xero or your ERP with the right accounts, so month-end close starts from matched figures.
• 3PL and logistics. Paid orders go to the warehouse automatically, and tracking numbers, shipping costs and returns come back to the store and the customer.
• CRM and marketing. Form fills, calls and purchases update HubSpot or Pipedrive, and closed deals are uploaded to Google Ads as offline conversions so bidding learns from real revenue.
• SaaS product integrations. Native connections your customers expect, such as a Shopify app install flow, a Slack notification or a two-way Google Calendar sync.

What Makes an Integration Hold Up in Production

Most integrations work on day one. The difference shows on the day a vendor slows down, sends a webhook twice or changes a field. These are the details we build in:

• Idempotency. Processing the same event twice must not create two orders or two invoices. Stripe supports idempotency keys on requests, and we store processed event IDs so repeated webhooks are ignored safely.
• Webhook verification. Incoming webhooks are checked against the sender's signature, for example the HMAC header Shopify sends, before we trust the payload.
• Rate limits and backoff. When an API returns HTTP 429, we slow down and retry with increasing delays instead of hammering it and getting blocked.
• Reconciliation jobs. Webhooks can be missed. A scheduled job compares both systems and fixes gaps, so the integration heals itself.
• Version tracking. Platforms like Shopify release new API versions on a regular schedule and retire old ones. We pin versions and record upgrade dates so a deprecation never catches you out.
• Token management. OAuth tokens are refreshed automatically and stored encrypted, never in the code.

When No-Code Tools Are Enough

No-code API integration solutions such as Zapier, Make and n8n handle simple, low-volume flows well, and we use them when they fit. Custom code makes sense once you need high volume, complex mapping, two-way sync, strict error handling or costs that would grow with every task run. Our comparison of n8n vs Zapier covers the no-code side, and our AI automation services team builds workflows that mix both.

Hiring an API Integration Company: Pros, Cons and Alternatives

API Integration Mistakes That Cost Orders and Invoices

• No single source of truth. Two systems both allowed to edit a customer's address will overwrite each other until nobody trusts either.
• Polling instead of webhooks. Checking for changes every minute burns rate limits and still misses events between runs.
• Silent failures. A sync that fails without an alert is discovered weeks later by an accountant or an angry customer.
• Credentials tied to one employee. When the person who connected the API leaves and their account is closed, the integration stops. We use service accounts or app-level credentials owned by the company.
• Ignoring time zones and currencies. Orders placed near midnight land on the wrong day in the ledger, and multi-currency stores post the wrong amounts.

Integrations We Run on Our Own Products

We co-build AM Jarvis, a SaaS suite for Shopify and WooCommerce stores. It imports products from Shopify, WooCommerce, AliExpress, Amazon and eBay, scans for and fixes Google Merchant Center violations, and runs AI rewriting on each user's own API keys for Claude, OpenAI, Gemini, DeepSeek or Groq. Our CMS pings IndexNow on publish and pulls Search Console keyword data into its admin. These integrations run every day, and maintaining them is how we learned where they break.

API Integration Tools and Platforms We Use

Why Choose 95 Solutions as Your API Integration Company

• We maintain integrations on our own products. AM Jarvis and our CMS depend on third-party APIs every day.
• We understand marketing data. Mustafa has 11+ years in digital marketing, so ad platform, analytics and conversion integrations are handled with the business context in mind.
• You own the code and credentials. Integrations run in your hosting, with API keys in your accounts.
• Senior-led with overlapping hours. Our founder leads strategy, and our hours cover the US business day and overlap UK hours.

Who Needs Custom API Integration Services

A good fit

• Businesses rekeying data between two or more systems every day.
• Teams whose Zapier bill or task failures have grown with volume.
• SaaS products that need integrations with the platforms their customers use.

Probably not a fit

• A single low-volume flow that an existing native integration already covers.
• Systems with no API and no export option. We can assess them, but options are limited.

API Integration Pricing

Integrations are quoted as a fixed price per flow or per milestone after we review each API. Larger programs start with a discovery sprint credited to the build. Monitoring, API version upgrades and changes run on a monthly retainer.

The main cost drivers are the number of flows, one-way versus two-way sync, record volume, how well each API is documented, whether a sandbox exists, and how complex the field mapping is. Posting Shopify orders to QuickBooks is a contained job; a two-way sync between an older ERP and three sales channels is a project.

For a quote on your integration, list the systems you want connected and we will reply with a custom estimate.

Next Step for Your API Integration Project

Send us the systems involved, what should happen when, and roughly how many records move each day. We reply within one business day, hold a short call to walk through the data flow, and then send a written scope with a fixed price per flow. If a native connector already does the job, we will point you to it. Integrations often feed a custom web application or need ongoing care through our web application maintenance plans.