Simple Made Easy – Lessons from Rich Hickey's Influential Talk

What makes software development a challenging yet rewarding field is not just writing functioning code, but understanding how to design systems that thrive in the long run. Rich Hickey’s 2011 talk, Simple Made Easy, is a timeless exploration of the principles that can help developers create reliable, maintainable, and scalable software. It’s a call to focus on simplicity, not just immediate ease, in everything we design.

This blog will unpack Hickey’s core concepts, breaking down why simplicity matters in software design, how pursuing ease can backfire, and actionable strategies to apply his philosophy in your day-to-day work. Whether you’re a seasoned developer or just starting out, Hickey’s talk offers valuable lessons to fine-tune your approach to software development.

Understanding 'Simple' vs. 'Easy' in Software Design

At the heart of Rich Hickey’s philosophy lies a powerful distinction between the terms simple and easy. While they’re often used interchangeably in everyday language, their meanings in the context of software design couldn’t be more different.

The Definitions

• Simple: Not intertwined or entangled. Simplicity refers to the clarity and singularity of a concept. Simple systems are uncomplected, meaning there’s no unnecessary interdependence between parts.
• Easy: Close at hand, familiar, or accessible. It refers to the relative effort (or lack thereof) required to perform a task. Easy is subjective, often linked to our existing knowledge or immediate convenience.

The Implications

Hickey argues that while easy solutions offer short-term comfort, they often introduce complexity over time. These choices prioritize immediate action over thoughtful design, resulting in tangled systems that are difficult to debug, extend, or reason about later. On the other hand, simplicity requires deliberate effort early on but pays dividends in long-term maintainability.

Etymological Insight

Hickey explains, “simple” originates from the Latin word “simplex,” which means “one fold”—unbraided and unentangled. Conversely, “complex” means “many folds.” Understanding these roots reframes simplicity as an attainable goal of clear, distinct parts working harmoniously.

Why Simplicity is Non-Negotiable in Software Design

The Dangers of Complexity

Incidental complexity creeps into software systems when developers choose convenience (e.g., familiar libraries or quick hacks) over sound design. This “complecting”—the intertwining of unrelated concerns or responsibilities—leads to fragmented logic, increased cognitive load, and technical debt.

Examples of complexity include:

• Unnecessary dependencies between different parts of the codebase.
• Stateful logic that causes unpredictable behavior depending on when or how it’s used.
• Overuse of abstraction layers, resulting in bloated code.

These issues can render a system unusable because understanding and modifying it becomes an uphill battle.

Simplicity as a Foundation

Simplicity fosters reliability, clarity, and adaptability. With fewer interdependencies, simple systems are:

• Easier to debug because individual components are isolated.
• More maintainable, enabling seamless updates or extensions in the future.
• Collaborative-friendly, as they are inherently easier for new team members to grasp.

Simplicity is not synonymous with minimalism; it’s about creating systems with intentional, untangled designs.

Examples of Simple vs. Easy in Practice

Simple Solution:

Imagine a scenario where you need to filter a list of customer data. A simple approach would use pure functions:

def filter_active_customers(customers):
    return [c for c in customers if c['is_active']]

This method is straightforward, stateless, and operates based on clear input-output relationships.

Easy Solution:

An easy solution might embed the logic into a shared global function with dependencies on mutable state:

filtered_customers = []
def filter_and_store(customers):
    global filtered_customers
    for c in customers:
        if c['is_active']:
            filtered_customers.append(c)

While this feels familiar and quick to implement, it introduces hidden complexity and potential bugs due to shared states.

Real-World Case of Simplicity in Action

Take Spotify’s use of immutable data structures in their backend design. Instead of managing mutable states, Spotify adopted a simple yet powerful paradigm that minimizes the risk of unintended side effects, enhances predictability, and ensures easier debugging.

How to Embrace Simplicity in Your Own Projects

Creating simple systems is easier said than done, but the following strategies can help you achieve Hickey’s vision:

1. Choose Composability Over Complecting

When designing systems, ensure each component serves a single responsibility and interacts with others via clear inputs and outputs. Avoid tying unrelated things together.

For instance:

• Use pure functions instead of methods that depend on external state.
• Prefer data-driven designs rather than abstract, stateful objects.

2. Refactor for Simplicity

Regularly revisit existing codebases to identify and untangle complexity. Use refactoring as an opportunity to simplify relationships and reduce dependencies.

3. Prioritize Clear Abstractions

Resist the temptation to over-engineer. Abstractions should provide clarity, not obfuscation. Utilize primitives like lists, maps, and sets before reaching for elaborate frameworks.

4. Invest in Understanding the Problem

Many of the most complex systems arise from misunderstanding the problem at hand. Take the time to truly understand the domain you're working on before jumping into implementation.

5. Advocate for Simplicity with Your Team

The benefits of simplicity extend beyond individual developers. Incorporate simplicity principles into your team’s development culture by:

• Sharing knowledge through code reviews.
• Hosting talks or workshops on simplicity versus easiness.
• Highlighting examples of simple designs during retrospectives.

Reducing Cognitive Load in Design

Hickey emphasizes that simplicity is vital because the human brain has limits. Studies show that we can only juggle 3-9 concepts at once. By minimizing interconnected logic and state, you’re not just creating better systems but also empowering your teammates to reason through designs effectively.

Building Better Software for the Long Haul

Rich Hickey’s Simple Made Easy talk is a vital reminder to prioritize long-term maintainability over short-term comfort in software development. Simplicity isn’t about cutting corners or limiting innovation. It’s about focusing on clarity, removing “complecting” dependencies, and designing systems that make life easier for future developers.

By choosing simplicity, you:

• Reduce cognitive strain.
• Create systems that are resilient to change.
• Improve collaboration within your team.

Take a moment to reflect on your own projects. What trade-offs are you making between simple and easy? Are there areas where incidental complexity has crept in?

If you’re ready to transform how you approach software design, start small. The next time you write code, pause and ask yourself, “Am I choosing simple?”