The Ruby Monolith Mindset: When Familiarity Breeds Technical Debt
The Ruby Monolith Mindset: When Familiarity Breeds Technical Debt
In the ever-evolving landscape of software development, certain patterns emerge that reflect not just technical decisions, but deeply ingrained psychological attachments to particular technologies. Recently, I encountered a situation that perfectly exemplifies this phenomenon: a modern company website, built as a Ruby monolith, struggling under the weight of its own architecture. This experience wasn't just about technical debt – it was a stark reminder of how familiarity with a technology can sometimes blind us to better solutions. The challenge wasn't unique to this particular company; it represents a broader pattern in the industry where development teams sometimes prioritize comfortable tools over optimal solutions.
The Real Cost of Ruby: Performance Metrics
When viewing benchmarks the performance differences between Ruby and JavaScript are clearly quite substantial:
Binary tree script
Input: 18
| Language | Time | Stddev | Peak Memory | Time (User) | Time (Sys) | Compiler/Runtime |
|---|---|---|---|---|---|---|
| javascript | 939ms | 14ms | 247.7MB | 1473ms | 283ms | bun 1.0.25 |
| javascript | 1395ms | 30ms | 261.0MB | 2187ms | 363ms | node 21.6.1 |
| ruby | 4037ms | 417ms | 123.9MB | 3920ms | 100ms | ruby/yjit 3.3.0 |
| ruby | timeout | 0.0ms | 85.3MB | 4930ms | 53ms | ruby 3.3.0 |
| ruby | timeout | 0.0ms | 679.9MB | 9080ms | 607ms | truffleruby 23.1.2 |
Input: 15
| Language | Time | Stddev | Peak Memory | Time (User) | Time (Sys) | Compiler/Runtime |
|---|---|---|---|---|---|---|
| javascript | 85ms | 3.6ms | 114.9MB | 70ms | 17ms | bun 1.0.25 |
| javascript | 140ms | 0.6ms | 87.4MB | 130ms | 37ms | node 21.6.1 |
| ruby | 408ms | 6.3ms | 36.4MB | 367ms | 27ms | ruby/yjit 3.3.0 |
| ruby | 856ms | 5.9ms | 36.4MB | 813ms | 20ms | ruby 3.3.0 |
| ruby | 910ms | 25ms | 437.3MB | - | - | - |
Note: while Ruby at first glance has lower memory usage this is because the chart measures peak usage as opposed to time normalized usage. JS is executing the instructions faster and therefore will use more memory during runtime at once.
Source We sourced all of our stats for this example from: https://programming-language-benchmarks.vercel.app/ruby-vs-javascript where you can find all the source code for these tests and many more on GitHub.
These performance metrics demonstrate that JavaScript consistently outperforms Ruby by a factor of nearly 3x across nearly all of the various computational tasks provided in the tests on their site. The gap isn't marginal – it's substantial enough to impact both user experience and infrastructure costs. These performance differences become particularly pronounced at scale, where even small efficiency gaps can translate into significant operational costs.
For example, in high-traffic scenarios where servers are processing thousands of requests per second, these performance differences can mean the difference between needing three servers versus one to handle the same load. This translates directly into higher infrastructure costs, increased maintenance overhead, and potentially degraded user experience during peak usage periods.
The most telling aspect of Ruby's performance challenges isn't just in raw computation speed, but in how these limitations compound in real-world applications. Memory usage often tends to spike under load, garbage collection can cause noticeable application pauses, and the overhead of Ruby's object model becomes increasingly apparent as applications scale. These aren't just theoretical concerns – they're practical limitations that directly impact user experience and infrastructure costs.
Addressing the ecosystem
JavaScript stands as one of the most versatile and well-supported programming languages in the industry, with an unmatched ecosystem of over 3 million npm packages covering every conceivable use case. Its dominance spans the entire technology stack, from powering modern frontend frameworks like React, Vue, and Angular to robust backend solutions with Node.js, Deno, and Bun. The language's flexibility allows developers to build everything from interactive websites and mobile apps (React Native) to desktop applications (Electron) and serverless functions, all while using the same core language.
While Ruby maintains a respectable ecosystem with around 170,000 gems and excels in web development through Ruby on Rails, it's not feasable to match JavaScript's sheer versatility and platform reach. JavaScript's ability to run natively in browsers, combined with its near-universal adoption in modern development stacks, makes it an ideal choice for developers who want to build any type of application on the modern web.
The Industry Shift: Learning from Giants
The migration away from monoliths in general isn't happening in isolation. Industry leaders have blazed this trail, providing valuable lessons for others to follow. GitHub's journey away from their monolithic pure Ruby architecture represents one of the most well-documented transitions in modern software development. The process wasn't just about changing technologies – it was about fundamentally rethinking how their application should be structured to meet modern demands.
Twitter, LinkedIn, SoundCloud, Grab, Parse, Twitch, and Deliveroo have all undergone or are in progress on similar transformations. Each of these companies started with monolith-based architectures and gradually migrated to more distributed, polyglot systems. These weren't arbitrary decisions driven by technological fashion – they were strategic responses to real scalability and performance challenges.
JavaScript's Rise: Understanding the Performance Edge
JavaScript's performance advantages stem from years of intensive development and optimization. The language has benefited from consistent support and investment from major technology companies, resulting in highly optimized engines like V8. The asynchronous nature of JavaScript, combined with its event-driven architecture, makes it particularly well-suited for modern web applications.
The flexibility of JavaScript's ecosystem has also played a crucial role in its performance advantages. The language has evolved to handle everything from front-end interactions to backend services, real-time communications, and even systems programming through Node.js. This versatility, combined with its performance characteristics, makes it a compelling choice for modern web applications.
The Static Content Paradox
Perhaps the most puzzling aspect of modern Ruby monoliths is their use for static content. Today's company websites often consist largely of unchanging content that could be served through static site generators or CDNs. Using a full Ruby application server for such cases represents a significant overallocation of resources.
The impact of this architectural mismatch extends beyond just performance. It affects development workflows, code maintainability, and maintenance overhead. Modern static site generators and JAMstack architectures offer compelling alternatives that can deliver better performance with significantly reduced complexity.
Breaking Free from the Monolith
The path away from a Ruby monolith isn't just about choosing a different programming language – it's about embracing modern architectural patterns that promote scalability and maintainability. This might mean adopting a microservices architecture, implementing a static-first approach for content-heavy sites, or using serverless architectures for specific components.
The key is to approach these transitions strategically. Companies like GitHub didn't simply rewrite their entire codebase overnight – they carefully identified components that would benefit most from migration and proceeded incrementally. This approach allows organizations to maintain stability while gradually improving their technical infrastructure.
The Human Factor: Beyond Technical Considerations
The attachment to Ruby monoliths often goes deeper than technical considerations. It's frequently rooted in team dynamics, existing skill sets, and organizational momentum. However, the cost of maintaining this attachment – in terms of performance, scalability, and maintenance – becomes increasingly difficult to justify as applications grow and evolving business needs demand more performant, and resource efficient solutions.
Looking Forward: A Pragmatic Approach
While Ruby isn't inherently unsuitable for all use cases, its limitations in performance-critical scenarios are well-documented. The challenge for modern development teams is to recognize when these limitations outweigh the benefits of familiarity. This doesn't mean abandoning Ruby entirely – rather, it means being strategic about where and how it's used.
Modern web development demands a more nuanced approach to technology selection. The success stories of companies that have migrated away from Ruby monoliths demonstrate that while the transition may be challenging, the benefits in terms of performance, scalability, and maintainability make it worthwhile.
Embracing Change
The movement away from Ruby monoliths represents more than just a technical transition – it's a shift in how we think about building modern web applications. As we look to the future, the key is not to dogmatically reject any particular technology but to make informed decisions based on concrete requirements and empirical data. The companies that thrive will be those that can balance the familiar with the optimal, making technology choices that serve their long-term strategic interests rather than short-term comfort zones.
The data here is clear: while Ruby has its place in the development ecosystem, defaulting to Ruby monoliths, and indeed monoliths in general for modern applications inevitably leads to unnecessary technical debt and performance limitations. The success stories of companies that have made the transition to more modern architectures provide a roadmap for others to follow. The question isn't whether to make this transition, but how to do so in a way that sets your organization up for long-term success.