The Silent Scalability Killer: Technical Debt in Post-Deployment Operations

We all know that building software is just the beginning. Once we deploy the software, we face the real work running it, accommodating increasing user counts, and making whatever adjustments may be required. This is when scalability becomes a factor needs must be met without demise.

After deployment, we must contend with an insidious foe to scalability: technical debt. We can discuss technical issues there until everyone involved in the project has a positive understanding of why we continually call for its management. But then, the post-deployment operational impact of technical debt, and its disastrous ability to prevent scalability is often unpopular to analyze.

In this post, we are going to explore how technical debt affects the way your system runs after it has been deployed. We will outline how technical debt manifests after software is deployed, what it can do to your ability to scale, and why the ongoing pursuit of managing technical debt is paramount to upholding the health and performance of your system.

What Is Technical Debt in Post-Deployment Operations?

Technical debt refers to the aftermath of pursuing short-term workarounds or even bad practice decisions around your software design and/or implementation. At first, it may seem pretty clever to employ the workaround since it can lead to more timely delivery or defect fixing. However, over a longer period of time, your “last” quick-fix accumulates, and you can end up with an inefficient and brittle system that requires more and more maintenance.

In post-deployment operations, technical debt may take several forms:

1. Legacy Code: Once effective Code has lost currency, the old code may now impose speed bottlenecks and slow down the entire underlying infrastructure.
2. Infrastructure Limits: Either physical or cloud infrastructure may not effectively scale to increased demand.
3. Documentation Gaps: Poor documentation creates challenges for new team members who are learning the system, and may create additional time to investigate, debug, and improve.
4. Integration Gaps: Integrating components and systems without long-term thinking may lead to increasing complexity, worsen inefficiencies, and, over time, lead to increased time and cost in changes and upgrades.
5. Automation Gaps: Lack or insufficient automation for deployment, monitoring, and scaling increases the human factor and with it possibilities for human error.

These gaps will stack up over time and create limits to increased scalability.

How Technical Debt Impacts Scalable Systems

Scalability is the ability of a system to handle load increases or added capabilities/functionality without resulting in a decrease in performance. While it is expected that managing performance challenges will become increasingly difficult as a system scales, technical debt will further compound the scalability challenge and handicap you in a variety of ways:

1. More Latency and Less Throughput
   Legacy systems with technical debt will generally yield longer response times and lower throughput. Existing “legacy” code could simply not be tuned to the hardware or infrastructure it is running on, and thus creates performance challenges as the system grows. As the number of users rises, request rates increase, and transaction counts increase, the existing code with its inefficiencies and the infrastructure will further frustrate time and again until the system itself reaches its limits, resulting in poor performance and issues.
   Now consider an example. A database query that works fine with a single-digit or two-digit number of records is unlikely to work fine with thousands of records. It is easy to see how the delays in one request affect the overall performance of the system, as the system continues to action requests and ultimately deteriorates performance.
2. Challenges with Scaling Infrastructure
   Infrastructure technical debt, like technical debt in general, can include poorly architected design or using legacy systems, and since it complicates scaling, you begin to see the issues arise. Adding resources, such as servers or instances in the cloud, may not result in the same performance because the infrastructure may not be designed to scale. Furthermore, scaling may require reconfiguring the infrastructure, which will be a pain point when there is technical debt present.
   For example, a cloud-based application was created with a monolithic application architecture. If there is increasing demand, then the monolithic application may become more difficult to scale as it is not possible to scale simply by adding instances or expanding parts of the application. The application may require re-architecting into a series of microservices, which can prove to be expensive and lengthy.
3. Growing Burden of Maintenance
   Continuous maintenance becomes burdened with time and money as the technical debt rises up which does not go away while post deployment in operation. You will feel the burden of ongoing maintenance is primarily in terms of continuous maintenance costs due to administrators, developers, and operations teams needing to spend increased time diagnosing issues, applying patches, and making manual fixes during the ongoing operation. As the system continues to grow in size, the frequency of maintenance will increase, directly impacting a team’s ability to scale the system.
   For example, if the application or service was created with a given amount of technical debt in the form of outdated deployment pipelines or outdated required manual intervention, then it would likely take teams longer to focus on and execute on growth rather than what appears to be constant re-work around failures or manual glitches during operational state.
4. Higher Possibility of System Failure
   When a system has technical debt, it becomes brittle and more prone to failure, especially when the demand for the system increases. An outdated or poorly integrated component may fail unexpectedly when under stress, creating downtime or degradation in service. The problems multiply as the system scales and are harder to resolve. The reason is, identifying and resolving the source of the issue takes more time and work in a complex environment. For example, a microservice that was hooked up precariously without knowing it would be scaled could fail when traffic is high, and the whole system could experience cascading failures. The more components are added to the system, the brittle it becomes, making one component failure possibly bring down the entire operation.
5. Loss of Agility to Respond to Change
   To some, scalability means dealing with increased load, but scalability also involves the ability to respond to new and changing demands on the business. If technical debt has not been done away with at each opportunity, a team will not be able to respond to cultural shifts or changes in the market as quickly or as effectively. One example of possible technical debt would be, it is easy to add new features to a system, but it becomes increasingly difficult over time, especially if this complex system suffers from technical debt.
   It can take considerable time, effort, and work in a system with a large amount of technical debt to modify a piece of functionality. The effort in modifying a functionality is only the tip of the iceberg. You then need to debug and test before it is deployed. All of this adds to the deployment of the new functionality. The deployments when a system is suffering from technical debt will take longer before you can scale or share new functionality with a wider audience.
6. Mixed Quality and Reliability
   As technical debt accumulates, the quality and reliability of the system deteriorate. The amount of work involved in fixing bugs and adding new features increases because technical debt also increases the complexity of the system. This is tied to the quality of the system, and quality becomes more like an illusion as the level of technical debt increases, and the quality of functionality is less productive, unreliable, and erratic. Eventually, inconsistencies in behavior can affect the scalability of a system. As the system expands in scope, the likelihood of problems such as crashing, data being corrupted, and inconsistent performance increases. Scaling the system without a sufficient level of debt-free code will resemble the goal of scaling the same system in an environment like the one described.
   For example, you can see how a bug introduced into a system due to rushed code in one piece of code is introduced due to sheer similarity is the root cause of creating a cascading failure. Scaling the system with high engagement begins when the system is pushed to its limits. Expect these issues to grow in severity and frequency.

Taking Care of Technical Debt for Scalability in Post-Deployment Operations

If you would like to maintain a level of sustainability for the purpose of scalability, it’s possible when you take care of technical debt regularly as a duty to your post-deployment operations. Because a full system rewrite/refactoring project is of little to no value, here are a handful of things that can be done to demonstrate ways to limit the impact of technical debt when scaling:

1. Refactor Legacy Code: Actively scanning and optimizing legacy code for third-party support can provide assurances to the evidence of the lessons learned when things get serious, when nothing engages to deal with performance bottlenecks.

2. Scalable Infrastructure: Using a cloud native architecture and infrastructure allows for scalability with minimal concern, and measuring the performance of the organization will demolish any intended effort. Utilize technologies such as containerization (like from, e.g., Docker) and orchestrators (e,g, as Kubernetes). By using a scalable architecture, you are also able to engage using scalability concepts in an agile manner and work on multiple agile initiatives simultaneously.

3. Automation and CI/CD: CI/CD strategies rely on automation when modifying the overall components of the enterprise systems operating within a consistent environment. These systems tend to have a certain level of cut-and-paste features, and these add to the amount of non-deployed work the proposals concern for work and humans. This slows them down, and plans for scheduling work will soon become challenging.

4. Document: It is vital to have up-to-date documentation on the operational management of functionality in your system, and how it could impact as it relates to your onboarding tasks or responsibility in handover to the desired organization to the developer, which is an important piece of context. Keeping all documentation updated will minimize new knowledge acquisition and may reduce the work of debugging, and confirm a functional level with a speedy recovery.

5. Technical Debt Audits: Schedule technical debt audits on a regular basis and allocate resources to tackle it before your organization faces problems related to scalability. Regularly adopting an organized manner of observing, monitoring, and managing your technical debt will allow your organization to maintain scalability in the long term.

Conclusion

Failure to manage technical debt will impact your ability to scale effectively in ongoing operations after your system is deployed. The impact of technical debt across the spectrum from performance bottleneck problems to the limits of your infrastructure will tend towards increasing with growth and lead to lower efficiencies in scaling new subcircuits. The relationship between technical debt will tend toward higher maintenance with technical debt, which brings higher failure risks, which leads to less flexibility to be able to respond quickly to new growth and expansion needs, and in turn leads to lower capacity for businesses to meet their growth and scalability demands.

If a business does not schedule periodic tracking of technical debt or work toward technical debt completion commitments, the cost of technical debt will continue to rise. Unanticipated growth will be stunted, followed by another collapse of your fragile infrastructure under the next business requirement. Technical debt creates a business opportunity cost of wasted human effort to consume, squandered costs from not recognizing the opportunity to construct scalable automated infrastructures to address variable or changing demands, as an organization matures to achieve its goals. It becomes critical for organizations to manage technical debt with refactoring of code, user documentation, or improving infrastructure in a way that will help to ensure the organization’s long-term capability of scalability as equity expectations emerge.