Beyond Serverless: Enriching Serverless Applications with APIs

In this blog post, we will explore serverless computing, the benefits of integrating APIs into serverless applications, and how ApyHub's utility APIs can extend capabilities for serverless development.
Beyond Serverless: Enriching Serverless Applications with APIs
Sohail Pathan
Last updated on February 28, 2024


Traditional software development usually involves activities around managing servers, provisioning resources, and in general, dealing with scalability challenges. Every developer in the world has had some experience with this.
However, there is a trend/methodology that has changed this paradigm. Serverless computing has changed the way software applications are being designed, developed, and deployed. At its core, serverless computing is a cloud computing mode/methodology that aims to enable developers and development teams to focus on writing code without having to manage any underlying infrastructure.

What is serverless computing and how does it work?

Serverless computing is a cloud application development and execution model that lets developers build and run code without managing servers and paying for idle cloud infrastructure. The application still runs on servers, but all the server management is done by cloud providers (Eg. AWS Lambda, Netlify, Cloudflare, and others).
Just to make things more simple: In serverless computing, developers just create backend functions — the parts of the application that perform specific tasks and functionalities — and then deploy them to a cloud provider. This means developers can focus more on their code and less on managing servers.
I liked this brief explainer video explaining serverless computing and its unique value.

What are the main advantages of serverless computing?

There is no doubt that serverless computing offers many benefits that evolve around streamlining the application development and deployment processes. Below are some of the key points:
  • (The most obvious one) - No Server maintenance required:
    The core idea and value of serverless is that developers don’t have to deal with and manage servers. That's because, in serverless, the servers are managed by the infrastructure provider. By hosting applications serverless, developers can focus on building applications and building value without having to worry about maintenance.
  • Quick deployments and updates:
    Another fascinating point about serverless is that it allows developers to deploy and update their functions in a quick and efficient way without being concerned about the underlying infrastructure. This ability to go faster can then naturally result in faster go-to-market and more agile development processes.
  • Auto Provisioning of computing resources:
    In serverless, resource provisioning is dynamic, precise, and in real-time. Whenever there is a surge/spike in usage, the system automatically scales to accommodate the increased demand.
  • Reduced infrastructure monitoring needs:
    Compared to traditional servers where developers have to monitor resource utilization and cost, serverless remove this hassle altogether.
  • Code can run closer to the end user, decreasing latency:
    Serverless computing makes applications run faster by spreading out their tasks over a worldwide network. By sending each task to the closest server to the user and by automatically handling more or fewer tasks as needed, serverless makes the application much more responsive.
  • Pay-Per-Use costing model:
    In a serverless application, the code only runs when the backend functions are needed. Developers then only have to pay for the number of times the function gets invoked.

What are some of the disadvantages of serverless computing?

Despite all the advantages, Serverless also comes with its own pitfalls.
  • Cold starts and effect on performance:
    When calling a function for the first time, it may take some time to start up, resulting in occasional instances of low latency.
    If the function isn't activated for an extended period, it becomes unresponsive and takes time to load again. Moreover, other factors such as the size and complexity of the function, which are usually due to external dependencies that take time to load - eventually add delays in execution as the function takes time to start.
  • Limited State Management:
    When a function is executed in a serverless environment, it does not retain any data or context from previous function invocations. Each function invocation is treated as independent and isolated, without any memory of previous invocations.
  • Testing and debugging are challenging:
    Since the cloud provider takes care of infrastructure, developers have less control over the environment. This makes testing harder while creating a copy of the environment for testing locally.
    An application built with serverless architecture becomes a network of interconnected services and functions. Debugging an issue may require tracing a path through multiple functions and services, which can become time-consuming and complicated.
  • Not Preferred for resource-intensive & long-running processes:
    Since Serverless providers charge for the amount of time the code is running, it may cost more to run an application with a long-running process and resource-heavy tasks.
  • Vendor lock-in is a risk:
    When developers use serverless services from a specific cloud provider, they rely heavily on their infrastructure and tools. Switching to another can be hard because each provider has their unique features, limitations, and standards.
  • Security Challenges:
    While cloud providers implement robust security measures, the shared responsibility model in cloud computing means developers are still responsible for securing application code from un-authorized access and updating dependencies.

Who should use a serverless architecture?

Serverless is ideal for developers and organizations who want to speed up the launch of their projects and create adaptable, easy-to-update apps without much complexity.
Also, developers who want to push part of their application functions closer to end users (for reduced latency) will require at least a partially serverless architecture, since doing so necessitates moving some processes out of the origin server.

When should developers avoid using a serverless architecture?

Despite all the obvious advantages, a serverless architecture is not the answer to everything and should not be used on certain occasions. In more detail, developers should avoid using serverless architecture:
  • When dealing with larger applications that have consistent and predictable workloads.
  • When having to migrate legacy applications to a serverless architecture that has uncertain infrastructure needs. This is where server-based setups seem to be a more viable option.

The Role of APIs in Serverless Applications

Serverless applications can invoke third-party APIs that provide complex functionalities that would be difficult to implement within a serverless application.

Benefits of Using APIs in Serverless Applications:

  • Integration Flexibility:
    APIs are the pathway for serverless applications to seamlessly connect with an extensive array of services and data sources. Typically serverless applications run as a single code block and use libraries to not reinvent the wheel, however, this creates a technology stack lock-in, where developers can only use libraries that are available in the same programming language as their serverless application. APIs allow developers to bypass this limitation to connect with remote services that provide capabilities and this flexibility allows them to create more complex serverless applications.
  • Rapid Development:
    APIs can make the development process leaner, and simpler since developers can leverage existing, tested, and well-documented solutions and can focus on building core functionality (and value) rather than spending time and effort reinventing the wheel. It allows faster iterations and quicker delivery to the market.
  • Vertical Scaling:
    Serverless applications can efficiently scale horizontally - It refers to the ability to handle increasing workloads by distributing them across multiple instances or functions. However, there can be a problem when vertical scalability is required. For example, an application needs to generate a thumbnail for a large video file. Processing this task locally becomes challenging due to limited memory and storage. However, by integrating third-party APIs, the video file can be sent in a payload to the API service, that processes the video and generate the thumbnail. This approach enables developers to achieve vertical scalability while utilizing serverless technology.
  • Cost Efficiency:
    When creating a serverless application, developers have to choose a higher limit on computational and memory resources because it cannot vertically autoscale. The complexity of a task or function is directly proportional to the computational power it requires. For tasks that may not require high computing power, developers still need to allocate higher resources because if the specified limits are set too low, the function may fail to perform adequately under peak loads. So, in the majority of cases where there is no need for such high computing power, developers still have to bear the cost of the unused resource. However, by leveraging third-party APIs, serverless applications can offload these tasks, delegating them to external services rather than executing them locally.
    Since the external service will be responsible for managing the infrastructure and scaling the resources to meet the demand, developers can only pay for the resources actually utilized.

ApyHub: The all-in-one API catalog

ApyHub is an API catalog. It offers more than 100+ Utilitiy APIs that help developers to integrate complex functionalities just using REST API calls and without building and deploying on their own. Since all API services are hosted within the ApyHub infrastructure, developers do not need to deal with and care for infrastructure provisioning.
ApyHub can become a great extension to the serverless computing model as it makes it possible to build and run application code in a serverless architecture with additional functionalities that would typically require some sort of server maintenance.

API catalog:

API Catalog
  • Image and Video Processing APIS: Provides functionality to quickly resize, crop, compress, or manipulate images and videos based on user requests.
  • E-Commerce APIs: Designed to streamline operations these APIs can help in, automate invoice generation, display product prices in various currencies, and generate barcodes or QR codes.
  • File Conversion APIs: Facilitate the conversion of various file formats to suit different needs, including text files to PDFs, Word documents to HTML, images to PDF, CSV to JSON, RSS to JSON, JPG/PNG to WebP, and video to multiple formats.
  • Artificial Intelligence APIs: Offer capabilities like text and document summarization, face and object detection, text content classification, and more.
  • Data Validation APIs: Ensure the accuracy and validity of data such as emails, postal codes, IFSC/BIC codes, SWIFT codes, and EU VAT numbers.
  • Data Extraction APIs: Extract valuable information like SERP rankings, readability scores, keyword analysis, language detection, link previews, and text from documents or web pages. These APIs are useful for SEO tools, content analysis, and enhancing data aggregation processes.
  • File Manipulation APIs: Provide functionalities such as changing or removing image backgrounds, extracting audio from video, applying watermarks, extracting metadata, and generating image thumbnails.
  • File Security APIs: Enhance the security of files through features like secure file archiving, image and PDF watermarking, and applying headers and footers to documents.
  • Smart Data Generation APIs: Generate useful data and content, including image thumbnails, file archives, text-to-speech and speech-to-text conversions, and iCal events.
  • Standard Data APIs: Provide access to essential data like time zones, currency conversion rates, country codes, and detailed country information.


Serverless computing is a great shift in application development, focusing on simplicity, scalability, and cost efficiency. The integration of APIs can further enhance the capabilities of serverless applications, allowing developers and development teams to create powerful, feature-rich solutions by leveraging and tapping external services. We do believe that as the serverless ecosystem and technology continue to evolve, the synergy between serverless computing and APIs will play a super important role in shaping the future of cloud-native application development.

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