Technical Debt in Microservices: Managing Dependencies and Debt

One of the solutions that can help to deal with technical debt is transitioning from a monolithic architecture to a microservices architecture. While this transition offers benefits such as enhanced scalability and resilience, it also introduces new challenges that must be addressed. How to manage technical debt in microservices?

Managing technical debt with microservices

One of the methods of reducing technical debt is transitioning from a monolithic architecture to microservices. The main reason behind this move is the challenge of modifying large, monolithic structures. Adopting a microservices approach is much more pragmatic, as refactoring a monolith into a modular architecture enables the creation of smaller components. This move makes it easier to implement and refactor components, ultimately mitigating the accumulation of technical debt and helping to pay it off. 

Microservices help to:

• build applications that are more adaptable to new requirements
• reduce dependencies between components, thereby facilitating the introduction of changes
• detect flaws and refactor low-quality code faster.
  

Unexpected consequences

However, the solution is not perfect and obviously has its drawbacks. Although it’s a recommended method, it doesn’t leave the software completely debt-free and might still accumulate some flaws after the migration. Additionally, it comes with new challenges and risks such as:

• creating an inefficient architecture that leads to excess complexity (and bad architecture is hardest type of debt to pay off)
• issues with managing debt in a distributed system
• updating every service or unit separately, as it requires more effort and attention 
• more time-consuming testing
• difficulties in ensuring security
• miscommunications between the development teams.

Why it’s hard to identify technical debt in microservices

Identifying technical debt in a microservices architecture presents unique challenges compared to traditional monolithic applications due to several factors inherent in the distributed nature of microservices. 

• Complex interdependencies: Microservices are designed to be independent, but they often rely on intricate networks of communication and data dependencies. These interdependencies can obscure the visibility of technical debt as issues in one service may have cascading effects on others, making it difficult to pinpoint the source of a problem. The distributed nature of microservices leads to complexity in interactions and dependencies, making it hard to assess the impact of changes or identify where technical debt may have a cascading effect.
• Diverse technologies and frameworks: Microservices architectures often leverage the flexibility to use different technologies, languages, and frameworks best suited for each service's functionality. While beneficial for addressing specific problems, this diversity complicates the consistent analysis and identification of technical debt across the entire ecosystem.

• Inter-service dependencies: While microservices are intended to be loosely coupled, in practice, dependencies and interactions between services can create hidden technical debt. Identifying and untangling these dependencies requires a deep understanding of the entire system's architecture and behavior, which can be time-consuming and complex.
• Operational overhead: The operational complexity of managing a microservices architecture, including deployment, monitoring, and scaling of services, can itself become a source of technical debt. Ensuring that operational practices and tools keep up with the growth of the system is a challenge.

Causes of technical debt in microservices

Complex inter-service communications

Overly complex or poorly designed communication mechanisms between services (e.g., excessive synchronous calls, improper use of messaging queues) can lead to tight coupling, increased latency, and reliability issues, contributing to technical debt.

Improper service boundaries

Incorrectly defined microservice boundaries that lead to either too much granularity (leading to chattiness and latency issues) or too large services (resulting in monolithic blocks within a microservices architecture) can accrue technical debt by making the system harder to maintain and scale.

Inadequate infrastructure and tooling

Insufficient or inappropriate infrastructure and tooling for deployment, monitoring, and scaling can lead to operational difficulties and limitations, contributing to technical debt by hindering efficient development and operation practices.

How to spot growing technical debt in microservices architecture

• Static Code Analysis: Use tools to analyze the codebase for common issues such as code smells, complex methods, and duplication. High complexity and duplication can indicate areas of technical debt.
• Dynamic Code Analysis: Performance profiling of services to identify bottlenecks, inefficient resource usage, or overly complex interactions between services.
• Evaluating dependencies: Evaluate the dependencies between microservices to identify tightly coupled services. High coupling can indicate technical debt, as it makes the system more fragile and harder to change.
• Looking for outdated libraries: Check for outdated libraries or frameworks that may no longer be supported or could limit the evolution of the service.
• Architecture review: Assess whether the microservices architecture still fits the system's needs. Overly granular services or improperly defined boundaries can create technical debt.

Now, let’s delve into the details on how to solve technical debt in microservices.

Reducing technical debt in microservices

Whether you've already migrated to microservices or are still in the planning stage, it's crucial to understand the risks and techniques for keeping technical debt in check.

Microservice architecture can complicate the identification of technical debt, indeed. You must thoroughly understand how all these modules function to detect technical debt and related issues swiftly and effectively. 

So, how to identify and minimize technical debt in microservices? Here are some tips and best practices from our software development experts:

<h3 id="modify">Modify units separately</h3>‍

In a microservice environment, each service represents a distinct functionality. To ensure easy maintenance and updates in such architecture, it's essential to ensure that each unit is robust and scalable. This approach simplifies the identification of flaws and their origins. Additionally, it is crucial to minimize dependencies between components and get a solid understanding of the architecture’s structure.

<h3 id="feature">Use feature toggle</h3>‍

Implementing feature toggles (or feature flags) can significantly simplify the configuration of microservices. It enables selective enabling and disabling of features without the need to redeploy the entire system. This approach also facilitates easier identification of problematic features, as you can clearly see which component is the source of the issue.

<h3 id="automate">Automate testing</h3>

Another valuable practice is automated testing. This approach aids in identifying flaws and bugs and preventing them from accumulating as technical debt without significant human involvement.

Foster the culture of code reviews‍

Regular code reviews should serve as the base for maintaining and updating code in a way that identifies and mitigates technical debt. Conducting reviews regularly helps to fix issues as they arise, and prevent the accumulation of debt over time when it becomes more costly to fix. Thus, it is recommended to become a common practice within your development team.

Collect user feedback

‍Another effective method is performing canary releases. This involves deploying the latest version of code to a small group of users before releasing it to the broader market. This approach allows for thorough testing of the code to ensure it is functional and bug-free before reaching a larger audience.

Create a technical debt policy‍

Creating a set of guidelines for addressing and resolving issues can be a handy tool in the technical debt management process. This policy should be communicated to all team members involved, ensuring they understand it and are able to comply and contribute. The collaborative effort fosters awareness of the issue and clarifies the necessary steps in reducing technical debt.

Apply agile software development methodologies‍

Adopting an agile approach to development and implementing standards such as DevOps or CI/CD are instrumental in maintaining high software development standards and monitoring the software's condition. Through frequent iterations and immediate bug fixing, these practices facilitate the cultivation of a quality-first coding culture.

Stay updated with technology trends

A primary cause of technical debt is the use or upkeep of outdated technologies. Swiftly adopting the latest technologies and integrating them into your environment can prevent the accumulation of debt over time and ensure your software remains modern. This prepares your code for easier and faster improvements.

Precautionary steps - How to prevent

Consistent coding standards and practices

• Establish and enforce coding standards across all microservices to maintain consistency and readability, which can help prevent the accumulation of technical debt.
• Adopt common patterns and practices for error handling, logging, and configuration management across services.

Emphasize automated testing

• Implement comprehensive automated testing strategies, including unit, integration, and end-to-end tests, to catch issues early and prevent bugs from becoming entrenched.
• Use contract testing to ensure that interactions between services remain stable over time.

Continuous Integration and Continuous Deployment (CI/CD)

• Leverage CI/CD pipelines to automate testing, build, and deployment processes, ensuring that code quality checks are consistently applied and reducing manual errors.
• Integrate static code analysis tools into the CI pipeline to automatically identify potential sources of technical debt.

Regular refactoring

• Make refactoring a regular part of the development cycle, addressing known issues and improving code quality incrementally without waiting for technical debt to accumulate.
• Encourage developers to leave the code better than they found it ("boy scout rule").

Why does technical debt happen in the first place?

To put it simply, technical debt refers to the decline in code quality that occurs over time. This happens for a few general reasons:

• unclear definition of requirements 
• lack of knowledge, experience and skills in a specific technology or general code writing
• creating quick, temporary solutions and cutting a few corners due to time pressure, and not improving them later
• bad design decisions that leads to difficulties in further development
• evolving business needs and goals that force changes to the selected solution or technology
• neglected code documentation and testing procedures
• technology evolution and delays in modernization
• poor technical leadership and collaboration between team members
• budget restrictions.

If we don’t address these issues early on, they pile up and cause numerous issues, such as decreased performance, prolonged development cycles, increased maintenance costs, bugs, difficulties with further code development, and other challenges. Then, it is crucial to solve them on a regular basis as soon as they are detected.

Your next steps - start with assessment to identify and prioritize tech debt

• Inventory services: List all the microservices in your system, including their dependencies, technologies used, and teams responsible for them.
• Identify pain points: Gather input from development, operations, and business teams about the challenges they face. This might include deployment difficulties, performance issues, or areas where frequent bugs occur.
• Code analysis: Use static code analysis tools to identify common issues such as code smells, complex code sections, duplication, and security vulnerabilities. Tools specific to the languages and frameworks you use can provide insights into potential problem areas.
• Review operational metrics: Analyze metrics related to service performance, availability, error rates, deployment frequency, and recovery times. High error rates or poor performance can indicate underlying technical debt.
• Assess testing and deployment practices: Evaluate the state of your automated tests, CI/CD pipelines, and deployment practices. Look for inadequate test coverage, flaky tests, or cumbersome deployment processes.
• Documentation review: Check the current state of your documentation for accuracy, completeness, and accessibility. Outdated or missing documentation is a form of technical debt.

Reduce your technical debt in microservices now

Technical debt is a serious issue that poses risks not only to code quality but to the entire business. It slows development, lowers developer morale and productivity, introduces security vulnerabilities, raises the number of bugs, decreases user satisfaction, diminishes competitive advantage, and more. Moreover, it boosts both development and software maintenance costs.

That's why reducing and paying off technical debt is essential in every software development project. The longer you delay or ignore it, the more damage it can inflict on your software and business. If you aim to expand your product seamlessly, align tech and business strategies, and maintain a satisfying pace of software delivery, reducing technical debt must be your top priority.

If you require assistance in reducing technical debt in microservices, don't hesitate to contact us. As experts in legacy app modernization, we will provide you with guidance on the optimal strategies for migrating from monolith to modular architecture and tackling the challenge of technical debt.