What is Lean Software Development?

As the software development landscape continues to evolve, so too do the methodologies that software development companies use to create and deliver products to customers. One of the most popular approaches in recent years is the agile movement where we have all these various methods that follow the Agile way.  One of these Agile frameworks is lean software development.  A central emphasis of lean software development is efficiency, constant improvement and elimination of waste. We’ll get to this shortly. 

Unlike traditional waterfall models, which often lead to delays and wasted resources, lean software development is designed to deliver value quickly and efficiently.  This explains why it has become a popular choice for businesses that want to move fast and stay firmly agile.

Of course sometimes it may not be easy to choose one agile methodology over the other with finality, but understanding each with clarity is always a good starting point. 

This article focuses on lean software development, what is it? Let’s find out. 

What is lean software development?

Lean software development (LSD) is an approach that emphasizes minimizing waste and optimizing efficiency. The lean approach is also known as the Minimum Viable Product (MVP) approach, where a team launches the bare-minimum version of a product to the market. The product development team learns from the users i.e. what the users would like added or what they don't like, and then makes changes based on this feedback. 

The lean approach has its roots in the 1980s lean manufacturing movement. So it’s fair to say that it borrows its ideas from the manufacturing industry, which gave rise to the lean approach as a way for assembly lines to maximize customer value, minimize waste, and optimize production. 

Toyota invented this methodology in the mid-20th century to streamline its car production process and eliminate time and resource wastage. Initially, the lean approach was called the Toyota Production System. The main operating principle of the approach in Toyota’s context was that any task that didn't impact the vehicle's functionality was considered a waste and removed from the process. 

Manufacturing organizations across numerous industries adopted this system rapidly, and the name changed to the Lean approach. It was first applied in software development around 2003.

The 7 principles of lean software development

The main idea behind the lean approach is to apply efficiencies and manage waste at all process levels. This idea is then broken down into what is collectively referred to as the principles of lean software development. If you would like to go deeper into this, then you might want to read «Lean Software Development: An Agile Toolkit», a book by Mary and Tom Poppendiek. In this book, they outline in detail how you can use the seven lean principles in software development. 

The principles are quite elaborate, but let’s gloss over the most important items of each of the seven principles. Here they are:

1. Eliminate waste

This is the first principle and it states that after each development cycle, the team discusses bottlenecks, identifies waste, and lays out a plan to eliminate them. The lean approach has a wide definition of waste, which includes anything that does not add value. The development team should eliminate all these wastes to maximize customer value.

Some examples of waste are:

• Unnecessary software features, codes, or functionality: These slow down feedback loops and wastes customer time.
• Starting more than you can complete: Adds complexity to the system, leading to context-switching, and other impediments to the process.
• Software development delays: Delays feedback loops and slows down time to customers.
• Constantly changing and unclear requirements: This can lead to a lack of focus, frustration, and quality issues and may result in rework.
• Bureaucracy: Slows down the entire software development process.
• Ineffective or slow communication: Slows down the process and leads to frustration. Furthermore, poor communication may negatively impact the development team's reputation.
• Partial work: Partially done jobs do not add value; hence the team cannot learn from them.
• Quality issues and defects: Leads to abandoned work, rework, and poor customer satisfaction.
• Task switching: This leads to communication breakdown, low team morale, delays, and poor quality work.

2.  Built-in quality

The software development team can use various tactics to ensure they build quality into the lean process. Such tactics include test-driven development (TDD) and pair programming. 

Though every team wants to build high-quality products, it is easier said than done. This is why quality is part of lean software development practices. However, many development teams create waste in trying to maintain quality, often through excessive logging of defects and testing.

In lean methodology, quality is not only the quality analyst's job but everyone's. Development teams use the following popular lean development tools to ensure quality in their work:

• Pair programming: This strategy combines the experience and skills of two developers to avoid quality issues.
• Test-driven development: Developers ensure their code meets business requirements by writing the code criteria before writing the code itself.
• Constant feedback and incremental development: The lean approach is a continuous improvement process that relies heavily on consumer feedback.
• Minimize wait states: The development team must reduce lack of focus, knowledge gaps, and context switching. 
• Automation: Automate manual and tedious processes that are prone to human error.

3. Amplify learning

Software engineers must share the knowledge they gain with every development team member. Knowledge sharing is done at meetings and through code review. Though this principle of creating knowledge seems simple, it requires focus and discipline to implement. The development teams must build an infrastructure for documenting and retaining valuable learning.

Teams can amplify learning through the following:

• Documentation
• Code reviews
• Pair programming
• Training
• Knowledge sharing sessions
• Wiki — letting the knowledge base grow incrementally
• Using tools to manage user stories and requirements
• Thoroughly commented code

4. Defer Commitment

A product development team delays commitment. This allows them to experiment and learn before committing to irreversible decisions. They incorporate functionality and features late in the process to avoid redoing the work as market conditions change. 

However, delaying commitment does not mean the team should be irresponsible and flaky in decision-making. Rather, the team should demonstrate responsibility by continuously collecting information and keeping their options open. This principle allows the development team to make decisions with all the necessary information.

To defer commitment means:

• Avoiding extensive pre-planned specifications for months to come.
• Not committing to projects and ideas before fully understanding the requirements.
• Regularly collecting and analyzing data regarding important decisions.

5. Deliver fast

Development teams want to deliver fast and put value into the customer's hands as quickly as possible. Lean software development is based on building a simple solution to provide quality products to the customer and enhance continuous improvement based on customer feedback.

To accomplish this, they must find out what slows them down. The following are some of the 'culprits':

• Over-engineering business requirements and solutions.
• Failing to respond to blockers with urgency.
• Predicting future needs too far in advance.

6. Respect for people

The principle of respecting people is the most neglected in software development's burnout-ridden, fast-paced world. Yet this principle applies to all the aspects of the lean development process, from how the teams handle conflict, communicate, hire and onboard new members, and deal with process improvement.  So it’s a critical principle that any professional software development company should never ignore. 

The lean approach encourages respect by:

• Encouraging healthy conflict.
• Empowering all members to do their best.
• Communicating effectively and proactively.
• Resolving all work-related issues as a team.

7. Optimize the whole

Development teams examine the lean process to optimize the value stream from start to finish. This means looking at all aspects of the process, from the way requirements are gathered to the way code is written and tested, and finding ways to improve each step. It's important to optimize not just individual steps, but also the overall flow of work, to make sure that bottlenecks are removed and work can move smoothly from one stage to the next. 

This principle is based on the understanding that suboptimization is a serious problem that should be eliminated completely.  Optimize not just the development stream, but all the streams within the organization because they will affect the development process in one way or the other, if not now later. This is precisely the role of the word “whole‘ in this principle. 

The lean practices

The lean approach has five essential best practices, which are:

1. Identify value: These are the customers' needs and requirements for the product.
2. Map the value: This includes all the processes and steps involved in delivering the final product.
3. Create flow: Ensure all the steps and processes flow smoothly without interruptions. 
4. Establish pull: Pull involves improving the flow and reducing the time it takes to deliver the product to the customer.
5. Seek perfection: Once you have accomplished practices 1-4, you should make the lean process part of the corporate culture. 

The main advantages of lean software development

• Efficiency: The lean approach delivers software fast and eliminates waste, making development teams more efficient and cost-effective.
• Collaboration: Lean processes amplify respect and learning to encourage knowledge sharing and teamwork. This enables teams to avoid bottlenecks and are empowered to work together in order to make better decisions.
• Flexibility: Developers can adjust the products easily, based on customer feedback.
• Continuous improvement: The lean approach is a modern software development process that incorporates customer feedback, enabling continuous improvement.
• Quality: Continuous improvement, flexibility, collaboration, and efficiency lead to a high-quality product and ultimately leads to high levels of customer satisfaction. 

Challenges of lean software development

Despite the numerous benefits, lean software development has a couple of challenges. They include:

• Team training requirements: The development efforts will suffer if the team cannot collaborate and communicate. So the team must be trained to adapt to changing initiatives and own each other’s work. They must trade duties and reorganize work as priorities change.
• Suboptimization: This occurs when only a part of the value stream is optimized. It happens when development teams break down a problem into pieces and solve each component in isolation without factoring in the effect of one part on the entire system. 
• Missing metrics: This often occurs when there are cases of the wrong metrics or when there are no metrics at all.
• No boundaries: In a lean approach, software requirements change as customers provide feedback. Too many changes and requirements create complexity and make it hard to deliver cohesive software.  

Recommended reading: The software development life cycle

Conclusion

As lean software development focuses on eliminating waste, it’s best suited for projects with a lot of emphasis on making savings especially on resources such as time and money.  This is important because costs can always go up fast when waste is not checked, especially the costs of custom software. 

So if your organization is working on a software project that you fear might end up accommodating a lot of waste along the way, then the lean methodology should be given front-row consideration.