The place of APIs in specifications

Integrating one or more APIs belonging to third-party systems is inevitable when developing a digital product. Whatever the type of project and its complexity, it's a must! As a start-up, you need to think about the type of API you'll need and, of course, express it clearly. Le Backyard lifts the veil on APIs and their importance in a specification!

I. APIs: an inescapable reality for all digital projects

Almost no digital project starts from scratch. That's why third-party APIs are essential tools when developing mobile applications, websites or any other digital product.

1. What is an API?

An API, or Application Programming Interface, is a software interface that acts as an intermediary to enable two different applications to communicate without knowing the details of their respective implementation. The aim is to enable them to exchange data or services.

There are several different types of API: 

• public APIs accessible to all;
• private APIs reserved for a certain number of users;
• Partner APIs accessible only to specific partners, subject to a signed contract.

In any case, when developing your product, the easiest way is to use a third-party service to benefit from its API. Indeed, creating one yourself from scratch is a long and costly challenge. 

2. What are the different types of API?

There are several types of API that facilitate the operation of the digital product you want to develop. Here are a few examples: 

• Mapping APIs: useful for entering a postal address or showing a location on a map. Google's APIs are the most widely used. 
• Payment APIs: these range from traditional bank APIs to private systems such as Stripe.
• Notification APIs: these can be email or SMS notifications. Brevo is an example of an API that provides this service.
• Mobile push notification APIs are used to notify users within an application. Firebase is the third-party service of choice.
• Video APIs: these can be used to create video streams, which are very useful for teleconsultation applications, for example, which require a great deal of videoconferencing.
• Chat APIs offer the possibility of chatting in real time, as well as sending images or videos. CometChat is regularly used for this function.
• Identity verification APIs are extremely important, especially for banking applications. These are KYC or KYB APIs.

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II. Anticipating costs

Of course, integrating APIs into your mobile application or website comes at a cost. That's why it's important to anticipate your product's API needs in your specifications, to avoid unpleasant surprises.

1. Integration is not necessarily free

An API is like a service provided by service providers, and service providers have to pay for it. Logically, the vast majority of APIs, such as those from Google or Stripe, are not free: sometimes from the outset, often on a pay-as-you-go basis.

To define the budget required, it is first important to distinguish between the following two costs:

• Integration costs: an initial investment (usually one shot) to connect the API to the system.
  
  
• Operating costs: recurring costs linked to actual use of the API.

2. Understanding API business models

Not all APIs operate on the same business model. That's why it's important to do your research upstream to make your choice, and to include cost information in your specifications.

API providers adopt a variety of models that can be more or less tailored to your needs:

• Free initial credit, followed by volume pricing (number of calls, bandwidth, etc.).
• Monthly subscriptions or commission-based models. This is the case with Stripe, for example, which charges €0.25 + a percentage per transaction.
• Sometimes, price lists are not available on the Internet. Start-ups are therefore obliged to enter into a direct contract with the supplier to find out the real costs.

3. Another option is to develop the API in-house

At Le Backyard, we recommend using third-party APIs that are already mature, immediately effective and easy to implement, rather than designing an API yourself. Indeed, building from scratch is often a time-consuming and costly challenge.

However, some start-ups prefer to avoid third-party APIs for reasons of data sovereignty or regulatory compliance.

This approach offers a number of advantages, including independence from third-party service providers and total control over business logic.

However, the initial development cost is considerable, which translates into a great deal of inversion on the part of the company. Added to this are ongoing maintenance requirements that should not be underestimated, and scalability issues that should be anticipated right from the design stage.

Thanks to its experience and constantly updated knowledge, Le Backyard is able to offer its customers the creation of their own API.

III. The importance of including an API component in your specifications

A project involving third-party APIs cannot be improvised. To avoid unpleasant surprises, the specifications must include precise technical and strategic elements.

1. A clear list of planned APIs

For each function, it's essential toidentify in advance the third-party services planned or envisaged. This enables you to :

• map dependencies from the outset;
• align stakeholders with technology choices ;
• anticipate costs and constraints.

Even if certain integrations are still being studied, mentioning them gives the service provider who will be responsible for implementing them some visibility, and avoids grey areas. So be exhaustive, even if you have doubts.

2. Provide technical documentation

To give service providers a good understanding of the APIs you wish to use, it is important to attach or indicate links to the technical documentation for the APIs in question. 

This saves precious time, makes it easier to estimate integration times, identify potential bottlenecks and prepare a coherent technical architecture.

Although Le Backyard has integrated dozens of APIs since its inception, there are many that we don't know about, because they're new or very nested. Good documentation is therefore essential, so that we can ask the right questions and calibrate our intervention.

3. Assessing legal dependencies

This may not seem obvious at first glance, but APIs are also subject to contractual constraints and freedom of use. It is therefore essential to consider this point when drawing up your specifications.

In particular, we need to identify the legal obligations linked to the use of each service (data storage, RGPD compliance, licenses, etc.) and anticipate the risks in the event of an API change: technical costs, architecture overhaul, temporary service disruption, etc.

4. Don't forget the importance of the technical stack

The choice of technical stack largely determines the ease with which certain APIs can be integrated. Not all APIs are compatible with all technologies.

Some stacks offer ready-to-use SDKs, libraries or plugins for common services (payment, mapping, notifications, etc.), while others require much more integration work.

Anticipating potential compatibilities or complexities as early as the specification writing phase is therefore essential to save time during development and make the best choices.

Although the specifications and API information contained therein are extremely useful for the agency accompanying the start-up in the development of the mobile application or website, they do not freeze the provider-client relationship.

Indeed, a good development agency will also do some investigative work of its own to ensure that the start-up's requests are beneficial to the development of the service.

This is where the agency plays a key advisory role, helping the start-up make the right choices. If you're planning to develop a digital product, Le Backyard can help. Don't hesitate to fill in our contact form to tell us more!