What Does It Take to Build an API Integration

4 min readJan 24, 2018


Everyone around seems excited about the benefits API economy brings. However, not many reveal the hard truth about how much effort building and maintaining an API integration really takes. Though being a completely necessary long-term investment, it has a few pitfalls which can challenge even the most exquisite mind. Hence, before pitching in, you’d better set a realistic views on the costs you are to invest into the integration.

Developing integration yourself

Companies, which once made integrations on their own, must have experienced all the difficulties of its development and control. The code could contain millions of lines (!), and still growing. Of course, it is unmanageable, and they had to give up. The result was wasted money, efforts and time.

Inconsistency is the problem

Connecting two systems with database requires a great deal of efforts and contains a few inconsistencies like the following:

  • They have different attributes and objects models
  • Sometimes systems have related attributes, but their format and values can differ
  • Conflicts will appear as artifacts by the changes users made

In order to overcome these and other challenges, you’ve got to have a consistent plan of what you have to do and what it will take. Here is the approximate scenario of what will happen once you decide to design your own integration.

First things first. Start with conducting a research

This is a basic step which software developers often underestimate. At the beginning it is crucial to get a fundamental understanding of the API: track every nuance concerning data structure, protocols, user authentication and reveal possible defects.

At the very best scenario, it can take three days to complete, depending on the complexity of the system.

2. Design a prototype

Further you’ve got to build a minimal functionality which would prove the ability of the API to connect. This is to let the developer understand the endpoint and learn more about the product. In total, designing stage may take around five days in total for developing the cloud document storage or CRM endpoints).

3. Create a basic version

Speaking in business terms, it is called a MVP — minimum viable product and basically means the same. After testing a prototype, it is high time to release a bare version with basic set of functionality. Budget another 10 days for that and keep in mind that you’ll require even more time to design the rest of the needed functions.

4. Manage transactions

This is the last step before presenting your API to the world, yet it is sometimes skipped due to being a challenging one. Mainly, transaction management is all about answering yourself what would you do if something fails or how would you withdraw the transaction. Obviously, you have not only to plan everything, but also to organize it in a way that it works smoothly and properly. This process requires from five up to ten days of work.

Congratulations. You have built an API

However, the work is not over yet. You have to invest your resources into maintaining the integration.

5. Keep servicing your integration.

  • Logging: dedicate around 3 days to log the transaction for debugging and support each time it is completed.
  • Monitoring: adding alerts and webhooks will take you around two or three days.
  • Documentation. No words are enough to stress the importance of this stage, though it is ignored so often. They say, your API is as good as your documentation is. So make sure you do not overlook this crucial moment and take two days to complete it.

Calculate the costs

To set a realistic view of what is waiting for you, add up the time suggested in this article and multiply it by the extent to which your developer is overloaded. In general developing an API takes around 1,5–2 months for building and infinity to maintain (by which I mean around 30% of original costs on a regular basis, not taking into account the salary for your project manager).

Knowledge is power. And now that you know how many resources have to be spent to develop the API, you can consider possible solutions and ways to cut down the costs.

API is only part of the answer

API provides access to the endpoint’s capabilities, artifacts etc. Yet keep in mind that APIs are primarily created for merchant’s convenience to build a multi-level business, not for a third-party integration. Therefore, an average API is often incomplete and documented poorly. Consequently, figuring out how to handle some issues requires plenty of attempts and mistakes made.

You might have a question in your mind, which may sound like ”how to overcome all these difficulties?” Here’s the solution for you!

Fortunately, API2Cart makes your integration easier, faster, safer and cheaper. It provides a unified API to connect with over 35 shopping carts. API2Cart solves practically all integrational issues for B2B eCommerce software merchants and helps them to expand their market share. Also, API2Cart protect consumer’s personal and store information from unauthorized access. The detailed documentation makes API using easier and more understandable, 24/7 customer support is always ready to help you.




API2Cart is a unified API provider that establishes integration with 40+ shopping carts, including Magento, WooCommerce, Bigcommerce, Shopify, PrestaShop, etc.