
Author
Co-founder, Apideck
Gertjan De Wilde is the co-founder and CEO of Apideck, a unified API platform that helps B2B SaaS companies launch accounting, CRM, HRIS, and other integrations without building and maintaining them individually.
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Third-Party API Integration: The Dependency Problem at Scale
Managing third-party API integration at scale means more than connecting to an endpoint. Here's what the versioning and dependency problem actually looks like in production.
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Financial API Integration: What It Is, How It Works, and What It Actually Costs to Get Right
A practical guide to financial API integration: types, how they work, what they cost to maintain, and how to choose between native builds, aggregators, and unified APIs.
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Custom API Integration for Accounting: What It Actually Costs to Build Your Own
Building a custom API integration for QuickBooks costs more than the initial sprint. Here's the real engineering cost: OAuth complexity, Intuit's 2025 pricing changes, data model gaps, and why AI features demand normalization from day one.
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Agent Auth: Why OAuth Wasn't Built for This
OAuth 2.0 was designed for clients known at build time. As AI agents make runtime decisions, delegate to sub-agents, and traverse trust boundaries, the cracks are showing. A practical breakdown of MCP OAuth 2.1, A2A, AAuth, WIMSE, and what a production-grade agent auth architecture looks like today.
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API Integration Services: What They Are and When to Use Them
A guide to the three types of API integration services: systems integrators, custom dev shops, and unified API platforms. With cost comparisons and a decision framework for SaaS and embedded finance teams.
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What is a Unified MCP Server?
A unified MCP server aggregates multiple providers in the same category behind one normalized AI interface. Learn what MCP servers are, why fragmentation is a problem, and how Apideck solves it.
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How to Build ERP Extensions: A Developer Guide to NetSuite, SAP, Business Central, Acumatica, and Sage Intacct
A developer guide to building extensions, embedded apps, and UI customizations in NetSuite (SuiteScript), Business Central (AL), SAP (BTP/B1 SDK), Acumatica (C#), and Sage Intacct (Platform Services).
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How We Built an MCP Server with 229 Tools (Without Writing a Single Tool Definition)
How Apideck auto-generated a 229-tool MCP server from an OpenAPI spec using Speakeasy, deployed on Vercel with dynamic tool discovery at 1,300 tokens. A walkthrough of the stack, the hosting tradeoffs, and the hard-won lessons from shipping serverless analytics.
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How to Integrate with the MoneyBird API in 2026
A practical guide to integrating with the MoneyBird API: OAuth vs personal tokens, pagination, filtering, rate limits, webhooks, and the synchronization API — with working Python examples.
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AI in Accounting in 2026: The Entire Stack Is Being Rebuilt From Scratch
AI in accounting isn't about features bolted onto old software. The entire stack (ledger, close, FP&A, audit, tax, payments) is being rebuilt from scratch by a new wave of well-funded startups. Here's the full map.
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Embedded Finance for Vertical SaaS: How Payments Became the Real Product
Vertical SaaS companies like Toast and Shopify now earn most of their revenue from embedded payments, lending, and banking. Real data on revenue, take rates, and the fintech stack that makes it work.
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Stablecoin APIs are the new payments infrastructure layer
A developer's guide to stablecoin APIs in 2026: Stripe, Circle, Fireblocks, Paxos, and the x402 agentic payment protocol. Covers API surface, custody models, gas fee abstraction, GENIUS Act compliance, and machine-to-machine payment flows.
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SAP Business One API Integration Guide: Authentication, Endpoints, and OData Queries
A practical guide to integrating with the SAP Business One Service Layer API. Covers session-based authentication, OData v4 endpoints, querying, pagination, User-Defined Fields, error handling, and production deployment tips.
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NetSuite OneWorld vs Standard: What Changes When You Hit the API
NetSuite OneWorld adds subsidiary tables, multi-currency fields, and schema differences that break integrations built for Standard. Here is what API and integration teams need to handle.
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Accrual vs Cash-Based Accounting: Geographic Differences and What They Mean for Your API
The rules around accrual and cash-based accounting vary by country, entity type, and business size. The US allows cash up to $31M in gross receipts. The UK now defaults to cash for sole traders. Germany requires accrual for most businesses. This post covers the regulatory differences across markets and what it means when you are building accounting integrations through APIs.
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Multi-Entity General Ledger Integration: What Changes When You Build Accounting APIs
Multi-entity accounting changes everything about GL integrations. Learn how NetSuite, QuickBooks, Xero, and Sage Intacct model subsidiaries differently, and how a unified accounting API normalizes the complexity.
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An introduction to the Stripe APIs: A Developer's Guide to Every API Surface
Stripe's API spans hundreds of endpoints across Payments, Billing, Connect, Radar, Issuing, Treasury, and Tax. This guide breaks down each API surface, when to use it, and how Apideck's upcoming Stripe Billing connector fits into the accounting integration picture.
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What Is ERP Banking? The Shift From Portal to Platform
ERP banking is the practice of embedding banking services directly inside ERP and accounting systems. This guide explains what it is, why it matters, how it works technically, and where the market is heading.
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Xero Scopes: What Changed and What It Means for Your Integration
Xero replaced two broad OAuth 2.0 scopes with ten granular ones for all apps created after March 2, 2026. Existing apps have until September 2027 to migrate. Here is what changed, what scopes you need, and how to handle the transition.
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How to Integrate With the SnelStart API
A technical guide to integrating with the SnelStart B2B API. Covers authentication, key endpoints, the certification process, and common challenges developers face when building accounting integrations for the Dutch market.
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Bank API Integration: How Banks Connect to Accounting and ERP Systems
Bank API integration connects banks to accounting platforms and ERP systems through standardized interfaces. This guide covers use cases from bank feeds and payment initiation to credit underwriting, the engineering challenges of supporting multiple platforms, and how unified APIs solve the fragmentation problem.
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Treasury Accounting: Why Every Fintech That Moves Money Needs ERP Integration
Your treasury product is working. Customers are depositing funds, earning yield, and paying bills from a single platform. Then the finance team calls. They need to reconcile treasury activity in QuickBooks. And suddenly your product creates more manual work than it eliminates.
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How to Integrate With the Oracle Fusion Cloud API
A developer guide to integrating with Oracle Fusion Cloud REST APIs. Covers authentication (basic auth, OAuth 2.0, JWT), API structure across ERP, HCM, SCM, and CX pillars, filtering, pagination, and when to use REST vs FBDI vs BICC vs business events.
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How to Integrate With the Campfire API
Campfire is an AI-native ERP for high-growth startups and mid-market companies. This guide covers integrating directly with the Campfire API and using a unified API like Apideck to connect to Campfire and 30+ other accounting platforms through a single integration.
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How to Integrate with the Odoo API
A practical guide to integrating with Odoo's API — covering authentication, core methods, accounting models (invoices, payments, chart of accounts), pagination, version handling, and webhooks.
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How to Integrate with the Horus Software API
A practical guide for developers building integrations with Horus Office. Covers OAuth 2 registration, authentication flow, API conventions, sideloading, and all key resources including folders, companies, book entries, invoices, and account histories.
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How to Integrate With the Pennylane API
A developer's guide to integrating with the Pennylane accounting API, covering authentication, invoicing workflows, rate limits, v1 to v2 migration, and practical tips for building production-ready integrations with the French accounting platform.
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Agentic Payments Are Rewriting Spend Management From Scratch
AI agents can now hold virtual Visa cards, execute purchases autonomously, and settle transactions with other agents. Every major payment network is racing to build the rails. Here is what it means for spend management and the fintech founders building the next layer of financial infrastructure.
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How to Integrate with the Rillet API in 2026
A practical guide to integrating with the Rillet API in 2026: authentication, pagination, idempotency, webhooks, incremental sync, financial reports, and the new MCP server for AI coding tools.
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Money movement infrastructure is fintech's most important layer
A category overview of the companies building ledger, payment operations, and money movement infrastructure, covering Formance and Modern Treasury through to Fragment, TigerBeetle, Column, and 20+ others shaping this space.
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Xero Integrations: The Complete Guide to Integration with Xero (2026)
Everything you need to know about integration with Xero in 2026: top apps by category, how to choose the right one, and what it takes to build a Xero integration into your own product.
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What Is Embedded Finance?
Embedded finance lets B2B SaaS and vertical SaaS companies offer payments, lending, banking, and more without becoming financial institutions. Here's what it means, which categories matter, and which vendors are building the infrastructure.
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OpenAPI Testing: The Complete Guide to Contract, Fuzz, and Integration Testing
Your OpenAPI spec is more than documentation. It's a testable contract. This guide covers every type of OpenAPI-driven testing, from contract and variation tests to fuzz testing and CI/CD integration, with tools like Portman, Inspectr, Schemathesis, Spectral, and Microcks.
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What Is a Webhook? How Webhooks Work, With Examples
Webhooks let one application push real-time data to another the moment an event happens. Learn how webhooks work, what a webhook endpoint is, how they compare to APIs and polling, see real-world examples from Stripe, GitHub, Slack, and Discord, and get practical guidance on building receivers, security, and testing.
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Accounting and ERP Integration for Banks: Use Cases, Examples, and Why It Matters
Banks are embedding financial services directly into accounting and ERP systems. Explore the key use cases driving this shift, from embedded payments and expense management to credit underwriting powered by real-time accounting data, with examples from J.P. Morgan, HSBC, Bank of America, and more.
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FX Payment Platforms: The Integration Guide for Cross-Border Payments
Every finance team running international operations knows the ritual: logging into one platform to check exchange rates, another to initiate payments, a third to hedge upcoming exposures. This guide maps the FX payment platform landscape, evaluates the API capabilities of every major provider, and explains how embedded FX payments are reshaping cross-border money movement.
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Treasury Management Systems: Multi-Bank Connectivity Guide
Every morning, in corporate finance offices around the world, a treasurer logs into the same banking portals, downloads the same statements as yesterday, and pastes them into the same spreadsheet in a slightly different format. Different portal. Different layout. Same manual ritual for thirty years. Until now.
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API Design Principles for the Agentic Era
For 15 years, developer experience meant optimizing for humans at a terminal. That model is increasingly incomplete. A growing share of API traffic is generated by AI agents that read docs, make decisions, and retry failures autonomously. This is the same discipline as DX applied to a new consumer. Call it agent experience, or AX.
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Stripe's llms.txt has an instructions section. That's a bigger deal than it sounds.
When Stripe added /llms.txt to their docs, most write-ups noted it as another company "embracing the AI era." They missed the interesting part. Buried inside is an instructions section no other company has built — Stripe programming what AI tools say about Stripe. Here's why that matters and what it means for your API.
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API Aggregator: What It Is, How It Works, and How to Choose One
Learn what an API aggregator is, how it works under the hood, and what to look for when choosing one. Covers open banking, accounting, HRIS, and CRM aggregators.
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How to integrate the QuickBooks Invoice API in 2026
Automating invoicing is one of the most common QuickBooks integrations. This guide covers the QuickBooks Invoice API in depth and shows how a unified API dramatically simplifies the developer experience.
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Understanding Tracking Dimensions in Accounting Integrations
Learn how tracking dimensions like departments, locations, classes, and custom categories work across QuickBooks, Xero, NetSuite, and Sage Intacct. Discover best practices for building accounting integrations that handle platform differences gracefully with dynamic dimension discovery, validation, and unified support.
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The Complete Guide to Exact Online API Integration in 2026
This guide covers everything you need to know about the Exact Online API: authentication flows, rate limits, endpoint patterns, common pitfalls, and how to build production-ready integrations without the typical headaches.
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Introducing the Intuit Enterprise Suite Connector
Intuit Enterprise Suite (IES) is Intuit’s AI-powered, cloud-native ERP for mid-market, multi-entity businesses that have outgrown QuickBooks Online. Apideck now supports full IES integration through its Unified Accounting API, allowing SaaS and fintech platforms to connect IES alongside QuickBooks Online and 20+ other ERPs.
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Xero API Pricing and the App Partner Program
Xero's new API pricing starts March 2026. Compare tiers, costs vs QuickBooks and Sage, plus 6 optimization strategies to reduce your integration expenses.
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Apideck Joins the OpenAPI Initiative
Apideck is now a proud member of the OpenAPI Initiative (OAI), the industry consortium driving the future of API standards under The Linux Foundation.
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Using Accounting APIs for Smart Lending Decisions
This comprehensive guide shows fintech developers and lending platforms how to transform raw accounting data into actionable credit insights using financial statement APIs and proven lending ratios.
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Construction Lending with Accounting APIs
This comprehensive guide shows you how to leverage accounting APIs to automate construction credit assessment, calculate industry-specific financial ratios, and build lending decisioning systems that understand the nuances of contractor financials.
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QuickBooks API Pricing and the Intuit App Partner Program
If you're planning to build an integration with the QuickBooks Online API, understanding the pricing structure is crucial for budgeting and architectural decisions. While the QuickBooks API was historically free with no volume restrictions, Intuit introduced a significant change in 2025 with the launch of the Intuit App Partner Program.
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Microsoft Dynamics 365 Business Central API Integration Guide 2026
Integrating Microsoft Dynamics 365 Business Central with your applications enables seamless data flow across finance, sales, and operations. By leveraging the Business Central API, developers can securely connect systems, streamline workflows, and reduce manual processes, creating a single source of truth that scales with business growth.
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Unified APIs vs. Zapier: What's the Difference and Who Are They For?
Discover the key differences between Unified APIs like Apideck and iPaaS tools like Zapier. Learn who they’re for, how they handle data, and which is right for your use case—whether you're building native integrations or automating workflows.
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Decoding the Differences between Embedded iPaaS and Unified APIs
This blog post delves into the differences between Unified APIs and Embedded iPaaS, exploring their features, and benefits to help you understand which option might best suit your integration needs.
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Announcing our $7.5m Series A
Today, we're thrilled to share some exciting news: Apideck has raised $7.5 million in our Series A funding round! This milestone is a significant step forward in our mission to simplify API integrations for businesses around the world.
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What is an SDK?
Software Development Kits (SDKs) are very common throughout the development landscape. Most API providers offer SDKs to help support specific programming languages and app development paradigms, making them an integral part of an overall developer support strategy. Below, we'll define what SDKs are, explore sample SDKs, and see how SDKs differ from APIs.
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What is OpenAPI? Introduction to OpenAPI Specification (OAS)
OpenAPI continues to evolve and sustain a vibrant, interconnected API economy. Here, we define what exactly OpenAPI is, how OpenAPI definitions are structured, explore a real-world OAS example, and look at how OpenAPI is becoming the foundation for AI agent interactions with APIs.
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What is a Unified API?
A Unified API is a single interface that connects your application to multiple APIs in the same software category through one standardized endpoint. You authenticate once, write your integration code once, and get normalized data back from any provider.
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Apideck Product Update 🚀 August 2020
New in Apideck this month: track all your integration requests in one place; build native integrations at scale with Apideck Unify; launching Channelstack.co.
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Apideck Product Update, November 2019
This blog post is the November edition of our monthly update with the latest updates on the Apideck platform. New features; redesigned landing pages, improved search, developer badges, HubSpot tracking, and Apideck Unify.
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Building a SaaS application in 2019 - SaaS Blocks 🧱
Hit the ground running when building a SaaS application. Buy-vs-build is a daily dilemma for product makers. SaaS Blocks helps you discover and select new vendors to add features to your SaaS product.
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Platform Heroes - Teamleader Marketplace, Niels Vanden Buverie
This interview with Niels from Teamleader highlights the importance of integration partners and community building to drive partnership success.
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Apideck Updates and SaaS Ecosystem News, February 2019 🚀
Upcoming Product Hunt launch. New features; Shadow listings, Catalog, Zaps page, Drift and Intercom support. SaaS News: Google Docs API, Slack Block Kit.
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Platform Heroes - Jake Wallace, AWeber
This interview with Jake from AWeber highlights the importance of customer alignment when building integrations and forging new partnerships.
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Platform Heroes - Jean-Pierre Pequito, Intercom App Store
Intercom has one of the most active developer ecosystems in the market. In this interview, we cover the Intercom App Store and what they have in store for the future!
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Platform Heroes - Corey Hobbs, GitHub Marketplace
The Gitub Marketplace is one of the most impressive B2D platform plays. Corey Hobbs shares his insights into their way of work and metrics.
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