The evolution of application architecture has seen a shift from integrated monolithic structures to the decoupled services of service-oriented architecture (SOA), leading up to today’s microservices and containers. These advancements prioritize flexibility and efficient, independent deployment, reshaping software development in the cloud era. Let’s explore each one.

The monolithic era

In the early days of computing, when applications were developed as monolithic architectures, every functionality was bundled together in a single application. The waterfall approach was king, with each development phase (requirements, design, implementation, testing, deployment, and maintenance) occurring sequentially. The advantage of monolithic applications was their simplicity as developers could easily understand the entire application and its dependencies. However, monolithic architectures had significant drawbacks:

• Limited scalability: Scaling monolithic applications took time as increasing capacity often required adding hardware or duplicating the entire application stack
• Rigidity: Making changes to monolithic applications was time-consuming as any modification required retesting and redeploying the entire application
• Slow release cycles: Due to the waterfall approach, it took longer to deliver new features and bug fixes since each development phase had to be completed before the next could begin

To overcome the limitations of monolithic architectures, developers began to adopt SOA in the early 2000s.

The advent of SOA

SOA is an architectural style that structures an application as a collection of loosely coupled, reusable services. These services communicate with each other using standard protocols and can be combined to create composite applications. The key advantages of SOA include the following:

• Reusability: Services can be reused across different applications, reducing development time and effort
• Modularity: Applications can be broken down into smaller, more manageable components, making it easier to maintain and update individual services
• Agility: Changes to one service do not require modifications to other services, allowing for faster release cycles

While SOA helped solve some challenges of Monoliths, it also comes with drawbacks, such as the increased complexity of managing and coordinating multiple services and the overhead introduced by the communication protocols between services.

Microservices and containers

Microservices, an evolution of SOA, are small, independent services that can be developed, deployed, and scaled independently. They communicate with each other via lightweight protocols such as HTTP/REST or message queues. Microservices offer several advantages over monolithic architectures and traditional SOA, including the following:

• Improved scalability: Each microservice can be scaled independently, allowing more efficient resource utilization
• Faster release cycles: Smaller code bases and independent deployment make delivering new features and bug fixes easier
• Better fault isolation: If a microservice fails, it is less likely to impact the entire application, improving overall system resilience

Containers, another key technology in the cloud-native landscape, provide a lightweight, portable way to package and deploy applications and their dependencies. Containers isolate applications from the underlying infrastructure, enabling them to run consistently across different environments. This isolation simplifies deployment and scaling, making containers perfect for microservices-based architectures. We will learn more details about this topic in upcoming chapters.

Figure 1.1 depicts the evolution from monolithic, where components are interdependent, to SOA, which introduces a service-based structure, and finally to microservices, where services are fully independent, embodying cloud-native flexibility and scalability:

Figure 1.1 – The evolution from monolithic to microservices-based systems

Lets take a moment to rewind the history of cloud computing, where cloud computing is a narrative of technological progress and conceptual breakthroughs. Time-sharing in the 1960s pioneered the efficient use of computer resources, but the real transformation began with the digital revolution of the 1990s, with the maturity of virtual machines and the early appearance of cloud computing. The internet’s proliferation enabled the application service provider (ASP) model to thrive, offering software solutions remotely. This model matured into Software-as-a-Service (SaaS), providing software on-demand via the internet, and later in the cloud, erasing the need for local installations. The journey continued with the creation of Infrastructure-as-a-Service (IaaS) and Platform-as-a-Service (PaaS), both of which further distanced software developers from the complexities of physical servers.

Note

The ASP model refers to provisioning software solutions via the internet. In this model, software applications are hosted remotely by the provider and made available to customers over a network, typically the internet.

Figure 1.2 represents timeline charts of key milestones in cloud computing’s history: from the 1960s’ mainframe computing and the 1972 internet emergence to the 1990s’ virtual machines by VMware and web services. The 2000s introduced AWS’s S3/EC2 services, followed by Google Apps and Microsoft Azure, culminating in the 2010s with the Office 365 SaaS offering and Docker’s containerization in 2020:

Figure 1.2 – Cloud computing timeline

These cloud-based services provided scalable and elastic infrastructure and development platforms, catalyzing the shift toward more agile, responsive, and cost-effective software development paradigms. This trajectory set the stage for today’s cloud-native applications, which are designed from the ground up to harness the distributed, service-oriented nature of the modern cloud.

Cloud computing solutions come tied with new software development practices, paradigms, and cycles. Automated cycles for building, deploying, and testing distributed and modular software have catalyzed the appearance of cloud-based services orbiting each of the software development and deployment phases.

Cloud computing service categories

Upon exploring cloud service models, we find SaaS for software access, PaaS for development platforms, and IaaS for infrastructure. These models form the foundation of cloud computing, addressing diverse digital needs. Let’s explore them further:

• SaaS: This is a distribution model where applications are hosted by a third-party provider and accessed by customers via the internet. In this model, the service provider takes care of hosting software applications and their corresponding data and ensures optimal execution by providing operating systems and underlying dependencies. Examples include Salesforce, NetSuite, and Concur.
• PaaS: This is a model where a third-party provider hosts application development platforms and tools on its infrastructure that can be accessed by customers via the internet. Compared to SaaS models, PaaS providers take less responsibility for software applications but are more committed to serving the operating system and its middleware. Examples include AWS Elastic Beanstalk, Google App Engine, and Heroku.
• IaaS: This is a model where a third-party provider hosts servers, storage, and various virtualized computing resources by offering them to customers via the internet. IaaS takes care of less abstract requirements, including networking, data handling, computing power, and ensuring virtualization layers. Examples include AWS, Microsoft Azure, and Google Compute Engine.

Benefits of cloud computing

There are many benefits of cloud computing if it is used right. In general, cloud computing has revolutionized the way we store, access, and process data. It offers a plethora of benefits for individuals and businesses alike, making it a preferred choice for modern computing needs.

The evolution and specialization of cloud computing techniques eventually matured to offer several benefits over traditional on-premises infrastructure, including the following:

• Scalability: Cloud services can be easily scaled up or down based on the demand, allowing applications to accommodate fluctuating workloads without overprovisioning resources
• Cost-effectiveness: Organizations can pay for only the resources they use, eliminating the need for upfront investments in hardware and software
• Flexibility: Cloud providers offer a wide range of services that can be used to build and deploy applications, enabling developers to choose the best tools and platforms for their specific needs
• Security and Compliance: Cloud providers often invest heavily in maintaining state-of-the-art security measures and compliance certifications, allowing organizations to leverage these protections for their applications and data

In addition to these advantages, cloud computing has democratized access to cutting-edge technologies such as machine learning, artificial intelligence, and big data analytics. By providing these capabilities as managed services, cloud providers have made it easier for developers to integrate advanced features into their applications, further driving innovation and growth in the software industry.

Consider the case of a start-up who wants to launch a new e-commerce platform. By leveraging cloud computing, the start-up could quickly and cost-effectively build, deploy, and scale its application without significant upfront investments in infrastructure or long-term commitments to a specific technology stack. This ability to rapidly adapt and grow would become invaluable as the business scale and customer needs evolve, demonstrating the power of cloud computing in driving innovation and efficiency in application development.

With such similar cases, cloud computing was bringing undeniable benefits to many businesses, which gave it the momentum to be ever-growing and further specialized to precisely meet evolving business needs. As businesses continued to adopt cloud computing within their operations, new specialized forms of cloud deployment models began to emerge, such as hybrid and multi-cloud deployments. This will be explored in more detail in the next section.

With businesses increasingly embracing cloud services, they began recognizing the potential benefits of not being tied to a single cloud provider for their diverse application and business needs. This insight led to the emergence of multi-cloud: a strategy that leverages multiple cloud service providers to address the unique requirements of an application or organization. In this section, we’ll delve into the factors that inspired developers to adopt multi-cloud strategies, the primary advantages it offers from a developer’s standpoint with the support of platform engineers, and the challenges they encounter when implementing a multi-cloud approach. We will also briefly distinguish multi-cloud from the related concept of hybrid cloud.

Multi-cloud versus hybrid cloud

Before diving into multi-cloud details, it is essential to understand the difference between multi-cloud and hybrid cloud since they are related but distinct concepts. Multi-cloud refers to using multiple cloud service providers to fulfill different aspects of an application or organization’s needs. In contrast, a hybrid cloud combines different public cloud services with private cloud or on-premises infrastructure. A hybrid cloud enables developers to maintain sensitive data and applications in a private or on-premises environment while leveraging public cloud services’ scalability and cost benefits for other workloads.

Though the two concepts differ, some developers may adopt a hybrid multi-cloud strategy for their applications by combining public and private clouds from multiple providers to meet their specific needs and application and business expectations. This approach offers both hybrid and multi-cloud strategy benefits, providing greater flexibility, cost optimization, and risk mitigation.

Note

Throughout this section, we will primarily focus on the multi-cloud concept while ensuring that the information and discussions provided apply to hybrid and multi-cloud cloud models.

• Private cloud (on-premises): A secure, proprietary network or a data center that supplies hosted services to a limited number of people, with certain access and permissions settings
• Public cloud: Computing services offered by third-party providers over the public internet, making them available to anyone who wants to use or purchase them
• Hybrid cloud: An environment that uses a mix of on-premises, private cloud, and public cloud services with orchestration between the two platforms, allowing for greater flexibility and optimization of existing infrastructure
• Multi-cloud: The use of multiple cloud computing services from different providers in a single heterogeneous architecture, to reduce reliance on any single vendor, increase flexibility, and mitigate against disasters

Figure 1.3 delineates the nuances between the following:

Figure 1.3 – Understanding the different cloud deployment models.

Understanding the significance of multi-cloud

As developers of the different organizations gained experience working with cloud services, they started to see the value of leveraging multiple cloud providers to address their application and business needs. This realization sparked the adoption of multi-cloud strategies, which involve using multiple cloud service providers to achieve a range of objectives.

Several factors contributed to the rise of multi-cloud, including the following:

• Avoid vendor lock-in: Developers who rely on a single cloud provider can find it challenging to switch to another provider or adopt new technologies in the future for the application demands. Typically, multi-cloud strategies help developers avoid this lock-in by using a mix of cloud services from different providers, enabling greater flexibility and freedom to innovate.
• Cost optimization: Each cloud provider has a pricing model and offers unique services and features. By using multiple cloud providers, developers can optimize costs by choosing the best services for their specific needs and taking advantage of price differences between providers, if this is done correctly.
• Performance and latency improvements: Using multiple cloud providers can improve application performance by distributing workloads across data centers and geographical locations, reducing end user latency.
• Compliance and regulatory requirements: Developers may need to comply with specific data residency or regulatory requirements that dictate where data can be stored and processed. Multi-cloud strategies enable developers to choose cloud providers that meet these requirements while still benefiting from the advantages of cloud computing.
• Risk mitigation and business continuity: Relying on a single cloud provider can pose risks in case of provider-specific outages or service disruptions. Multi-cloud strategies help developers mitigate these risks by distributing workloads across multiple providers, ensuring application resilience.

Challenges of multi-cloud

While implementing a multi-cloud strategy offers numerous advantages, developers, along with platform engineers (who manage the underlying platform for modern applications), must also navigate a unique set of challenges. In this section, we’ll discuss some critical hurdles developers may face during multi-cloud implementation and provide insights on overcoming them effectively:

• Increased complexity: Managing multiple cloud providers adds complexity to development and operations as developers must deal with different management interfaces, APIs, and service offerings, where still platform engineers play the role of simplifying these complexities.
• Security and compliance concerns: Ensuring consistent security and compliance across multiple cloud providers can be challenging as each provider has its security features and configurations.
• Data management and integration: Integrating data and applications across multiple cloud providers can be complex, requiring robust data management strategies and tools to ensure data consistency, integrity, and availability.
• Cost management: While multi-cloud strategies can optimize costs, they can also make tracking and controlling expenses across different providers and services more difficult. Platform engineers need to implement comprehensive cost management tools and practices to maximize the benefits of their multi-cloud strategy for developers.

As we progress through this book, we’ll discuss strategies and best practices from a developer’s perspective for overcoming these challenges and successfully implementing a multi-cloud strategy that optimizes cost, performance, and resilience. We’ll delve deeper into the principles and architecture of cloud-native applications, explore tools and technologies that facilitate multi-cloud development, and examine real-world examples to help you apply these concepts in your projects.

With a solid multi-cloud and cloud-native development foundation, you’ll be well-prepared to tackle the challenges and opportunities of building and deploying modern applications in a multi-cloud world. Stay with us as we explore this exciting new frontier in software development.

The advent of cloud-native technologies marks a paradigm shift in application development and deployment. Embracing cloud-native principles means moving away from monolithic architectures to more dynamic, scalable, and resilient systems. These principles, which are deeply rooted in microservices, containerization, and orchestration, enable applications to leverage the full potential of cloud environments. The automation of development phases is also a central element in cloud-native development. The ability to automate processes in software development, from deployment to testing, is leveraged by modern development teams to increase delivery frequencies. The dynamic management of resource allocation from cloud providers is also essential for establishing a cost-effective cloud-native strategy. Let’s have a closer look at these principles.

Figure 1.4 traces the software development evolution: waterfall methods and monolithic structures on physical servers in the 1980s, transitioning to Agile practices with N-tier architectures and virtual servers in the 1990s. The 2000s integrated DevOps with microservices and containers, leading to today’s cloud-based infrastructures:

Figure 1.4 – The evolution of the application development process

As we discussed earlier, microservices architecture, a cornerstone of cloud-native design, allows for the development of applications as a suite of small, independently deployable services. This approach contrasts sharply with traditional monolithic architectures, where applications are developed as a single, indivisible unit. Microservices offer increased modularity, making applications easier to develop, test, deploy, and scale.

Containerization further revolutionizes deployment. Containers package an application with all its dependencies, ensuring consistency across environments from development to production. This encapsulation aligns perfectly with the cloud-native ethos of building applications that are environment-agnostic.

Orchestration tools such as Kubernetes play a pivotal role in managing these containerized applications and automating deployment, scaling, and operations. This ensures that applications can seamlessly scale to meet demand, maintain high availability, and recover from failures more efficiently.

The shift to cloud-native is not just technical; it also represents a cultural change within organizations. Embracing cloud-native principles often requires adopting new methodologies such as Agile and DevOps, fostering a culture of continuous integration and continuous delivery (CI/CD), where small, frequent updates are the norm. These principles also lay the groundwork for automating software processes.

Cloud-native would not be a complete strategy if it was not cost-effective. Dynamic management and the ability to allocate resources on the fly are crucial for making cloud-native a profitable solution. Platform engineers should ensure that resources are allocated dynamically in response to fluctuating demand, avoiding unnecessary costs of overprovisioning.

Remember, whatever we have mentioned so far is just the tip of the iceberg to give you a holistic idea and to get you prepared for the journey ahead. So, stay tuned – we will discuss this topic in more detail in upcoming chapters.

The cloud-native advantage

Adopting cloud-native development provides a range of compelling benefits that drive modern developers to embrace this approach. These advantages include the following:

• Improved agility: Cloud-native applications can be developed and deployed more quickly, allowing organizations to respond rapidly to changing market demands and continuously deliver value to their customers. This is partly due to CI/CD pipelines, which automate application building, testing, and deployment, ensuring rapid and reliable releases.
• Enhanced scalability: Applications designed for the cloud can quickly scale to accommodate fluctuating workloads, ensuring optimal resource utilization and maintaining consistent performance even under heavy loads.
• Greater resilience: Cloud-native applications are built to be fault-tolerant, reducing the impact of infrastructure failures on application performance and enabling the system to recover quickly from unexpected events.

Overcoming cloud-native challenges

Despite the undeniable advantages of cloud-native development, developers may encounter challenges as they transition to this new paradigm. Some of the most common challenges include the following:

• Increased complexity: Managing distributed systems in a cloud-native environment can be more complex than traditional monolithic or service-oriented architectures, requiring developers to adopt new tools, techniques, and best practices
• New skills and expertise: To fully embrace cloud-native development, developers must acquire new skills and expertise in cloud-native technologies, such as container orchestration, microservices patterns, and serverless computing

Let's take a use case. It could be a start-up or enterprise that is planning to transition from a traditional application architecture to a cloud-native approach. By embracing cloud-native development, we can quickly iterate and deploy new features to meet its ever-growing user base's changing needs. Moreover, it can ensure that its infrastructure can scale to handle the demands of millions of users worldwide while maintaining excellent performance and reliability. But to achieve this, they must tackle some complex challenges, as mentioned previously, and have the right skills. Without these, the world of cloud-native technology might feel too complicated

As we move through this journey together, we will share tips, best practices, and hands-on examples to help you build the necessary skills and knowledge to excel in cloud-native development and confidently navigate its challenges.

When cloud-native meets multi-cloud

At this juncture, you should have acquired some basics and gained clarity on why multi-cloud and cloud-native development are two key approaches that, when combined, empower developers to make the most of their strengths. By skillfully merging the benefits of cloud-native technologies with the adaptability of a multi-cloud strategy, developers can create strong, scalable, and innovative applications that effectively meet the ever-changing needs of users and businesses.

It is important to understand that when cloud-native development and multi-cloud strategies are thoughtfully integrated, they complement each other to offer a wide range of benefits. Let's see how:

• Enhanced adaptability: A multi-cloud approach allows developers to select and combine services from different cloud providers, enabling them to adapt to changing requirements or embrace emerging technologies. Cloud-native development practices empower developers to rapidly build and deploy new features, further increasing this adaptability.
• Robustness and high availability: Merging the inherent fault tolerance of cloud-native applications with the redundancy offered by a multi-cloud strategy results in applications that can recover from failures quickly and maintain high availability across multiple cloud providers.
• Streamlined performance: Developers can distribute workloads across various cloud providers and choose the best services for each part of their application, leading to seamless performance and efficient resource utilization.
• Cost efficiency: Leveraging a multi-cloud approach allows developers to capitalize on the most cost-effective services from different providers. In conjunction with cloud-native development practices, this can lead to significant cost savings by optimizing resource usage.
• Independence from vendors: Adopting a multi-cloud strategy enables developers to minimize dependence on a single cloud provider, allowing them to switch providers or utilize new services without affecting their cloud-native applications.

As illustrated in the following figure, the synergy between cloud-native and multi-cloud emphasizes the importance of integrating these two paradigms in today’s application development landscape.

By adopting cloud-native principles, developers can create applications that are inherently scalable and resilient. Simultaneously, utilizing multi-cloud strategies allows them to leverage the best services and features from multiple cloud providers. This approach fosters greater flexibility and innovation, ultimately leading to the development of more efficient, reliable, and adaptable applications.

Figure 1.5 illustrates the progression of multi-cloud and cloud-native applications: starting with cloud adoption through data centers and virtual machines, evolving to cloud automation and culture transformation with DevOps, to accelerating digital projects with cloud-native apps, and finally to achieving enterprise transformation with multi-cloud native apps for optimal efficiency and scale:

Figure 1.5 – The synergy and journey of multi-cloud and cloud-native applications

Overcoming challenges

While the integration of cloud-native development and multi-cloud strategies offers numerous benefits, it also introduces some challenges. In this section, we’ll discuss common challenges developers might face and suggest approaches to overcoming them.

Managing complexity

The nature of cloud-native and multi-cloud strategies combination can organically lead to increased complexity as developers have been tasked to understand handled multiple services, cloud providers, and distributed systems. To overcome this challenge, here are some basic tips to consider:

• Tools such as Kubernetes, Terraform, and Ansible, which can help manage and automate the deployment, scaling, and monitoring of your applications across multiple clouds
• Centralizing logs and metrics from various cloud providers, which can provide better visibility into your applications’ performance and simplify troubleshooting

Ensuring security and compliance

Security and compliance are critical aspects of any application, and multi-cloud environments can introduce additional risks. To mitigate these risks, do the following:

• Implement consistent security policies and controls across all cloud providers, ensuring that access controls, encryption, and other security measures are uniformly applied
• Regularly audit your multi-cloud environment to identify potential vulnerabilities and maintain compliance with relevant regulations

Managing costs

While a multi-cloud strategy can lead to cost savings, it may also increase the complexity of cost management. To effectively manage costs, do the following:

• Monitor and analyze resource usage across different cloud providers to identify inefficiencies and optimize resource allocation
• Leverage cost management tools to track spending and set budgets or alerts based on your organization’s requirements

Acquiring and developing skills

Mastering cloud-native development and multi-cloud strategies requires developers to acquire new skills and knowledge. To address this challenge, do the following:

• Invest in training and certification programs to help developers acquire the necessary skills to work with cloud providers and cloud-native technologies
• Encourage knowledge sharing and collaboration among team members, fostering a culture of continuous learning and improvement

By addressing these challenges head-on, developers can fully harness the power of cloud-native development and multi-cloud strategies, unlocking their potential to build innovative, efficient, and resilient applications.

Moreover, the advent of cloud computing also fostered the rise of DevOps practices, emphasizing collaboration between development and operations teams to ensure faster, more reliable software delivery. By automating processes such as testing, deployment, and monitoring, cloud platforms enable teams to work more efficiently and reduce the risk of errors, further accelerating the pace of innovation in application development. We will cover the role of DevOps and platform engineering at the end of this chapter, so stay tuned.

As we come to the end of this chapter, It is important to state that the evolution to cloud-native development is a testament to a profound shift in the cultural landscape of software development. For developers, this shift is not just about adopting new technologies; it's about embracing a fundamental transformation in how development teams operate and interact.
Historically, development followed a project-based approach, characterized by distinct phases and a hand-off mentality. Teams would work in silos, focusing solely on their part of the project, often in a linear and compartmentalized fashion. This traditional model, while structured, proved inflexible and often misaligned with the dynamic nature of user needs and market demands.

The advent of cloud-native development has ushered in an era of product-centric thinking. In this paradigm, teams are not just builders but also custodians of the product throughout its life cycle. This holistic approach fosters a continuous development cycle, embedding feedback loops that resonate closely with user needs and business objectives. It's a transformative mindset that shifts the focus from merely creating software to nurturing and evolving it in sync with the ever-changing technology landscape and user expectations.

In the traditional waterfall development cycles, rigidity and hierarchy were the norms. Departments with specialized roles operated within strict boundaries, adhering to a linear development trajectory. However, cloud-native development breaks these barriers. It leverages the strengths of cloud providers, not only in terms of robust infrastructure but also through advanced technology stacks and development tools. This synergy gives rise to a novel paradigm, one that demands a reconfiguration of traditional business structures. As companies migrate to the cloud, they encounter structural shifts, necessitating a reorientation of departments and development workflows. This digital transformation calls for readiness at all organizational levels to embrace changes in roles, responsibilities, and methodologies.

In the cloud-native culture, agility and resilience take center stage. Developers, no longer confined to narrow roles, embrace comprehensive practices such as the Agile methodology and DevOps. These approaches enhance collaboration and streamline processes, ensuring that teams can respond swiftly and effectively to changes. Automation and CI/CD pipelines become critical, not just for efficiency but also for the reliability and predictability they bring to application deployment. This culture prioritizes customer-centric design, urging developers to deeply understand user experiences and craft solutions that are not just functional but also intuitive and engaging.

In a nutshell, transitioning to cloud-native is an intricate dance of adopting cutting-edge technologies and nurturing a mindset that champions adaptability, customer focus, and perpetual evolution. This cultural metamorphosis is crucial for organizations aiming to maintain their competitive edge in the fast-paced digital arena. As we delve deeper into the nuances of cloud-native development, particularly the roles of DevOps and platform engineering in multi-cloud environments, it will make these statement clear that this shift is not just a trend but a fundamental redefinition of how software is developed, deployed, and sustained. With that said, let's have a high-level view of how these cultural transformations align with today's internal team hierarchies. This is one example where each individual team fits in the pyramid structure

Figure 1.6 – Cloud-Native Value Pyramid

With this, we have come to the end of the chapter.

In this chapter, we've established a solid foundation for understanding multi-cloud and cloud-native development. To recap, we started with the essentials the evolution of cloud computing and its expansion into hybrid and multi-cloud environments, examining their advantages and challenges. We then learned how cloud-native development synergizes with multi-cloud strategies and the hurdles developers face in adopting these advanced methodologies. Lastly, we emphasized the importance of cultural and mindset shifts in this rapidly changing domain.

As we close this chapter, we have set the stage for a deeper exploration of the principles and architecture of cloud-native applications in Chapter 2, Building the Backbone of Cloud-Native Applications. Our journey will take us through the intricacies of designing, developing, and deploying cloud-native applications in multi-cloud environments, enriched by real-world examples, best practices, and practical exercises.

Together, we will navigate the exciting landscape of multi-cloud and cloud-native development, empowering you with the skills and knowledge necessary to confidently create and manage cutting-edge applications in a multi-cloud world. Let’s continue this enlightening journey and unlock the full potential of multi-cloud and cloud-native development for developers like you.