​I'm disappointed with the functional programming community. I was expecting higher-level thinking – freer thinking, commensurate with the intellectual freedom Clojure itself offers – but the atmosphere proved to be a shallow puddle of sectarianism​. That probably has its reasons – being marginalised as a community is probably one of them – but the end result remains unchanged.

The patterns are unmistakable. Knowledge as gatekeeping: the endless monad tutorial phenomenon, where every advocate believes they can explain monads better than everyone else, typically through increasingly baroque metaphors involving burritos, space suits, or elephants. This isn't pedagogy; it's ritual initiation. The complexity serves a social function – maintaining boundaries between insiders and outsiders.

Purity as virtue signalling: debates about whether using `IO` makes you impure, whether exceptions violate functional principles, whether mutation in bounded contexts is acceptable. These discussions frame technical trade-offs as moral categories, as though architectural design were a moral discipline rather than an engineering one. The language reveals it – clean, pure, disciplined versus dirty, impure, undisciplined. This is religious vocabulary applied to software engineering.

Terminology as tribal marker: deliberate retention of academic terminology when simpler terms exist. Endofunctor, catamorphism, anamorphism when 'map over containers', 'fold', 'unfold' would suffice. The obscurity is the point – it establishes hierarchy and demonstrates membership.

The emphasis falls on mathematical elegance rather than problem-solving. The question isn't Does this help ship software but Is this theoretically sound. People who can recite monad laws but have never shipped a product receive more status than developers applying functional patterns to solve actual problems.

Then there's the missionary behaviour: the conviction that imperative programmers need conversion. The framework isn't Here's another useful tool but You're doing it wrong until you see the light. This creates antagonism rather than adoption.

Being marginalised as a community probably explains some of this – defensive posture manifesting as increased boundary enforcement, which creates insider/outsider distinctions, which enables status hierarchies based on doctrinal purity. But understanding the cause doesn't change the result, and it doesn't make the behaviour intellectually rigorous or practically useful.

​Here's the substantive issue: finding Ooloi collaborators in FP communities is statistically improbable because very few people occupy my intersection point between various disciplines.

Music notation requires an understanding of compositional structure, engraving conventions, and how musicians actually work. Functional architecture requires a sophisticated understanding of immutability, higher-order functions, transducers, STM transactions, and compositional patterns. Backend infrastructure requires a willingness to work on unglamorous problems like endpoint resolution and temporal traversal rather than visible features, and in Ooloi's case, an understanding of server technology and secure cloud operations.

The population at that intersection is approximately one.

FP communities might yield people who appreciate my transducer implementations or STM transaction handling. But they won't understand why endpoint resolution for slurs matters, how temporal traversal serves musical structure, or what makes intelligent engraving different from geometric placement. The domain expertise is orthogonal to FP community concentration.

The inverse holds equally: musicians who understand notation deeply rarely have the architectural sophistication to work on Ooloi's core, and even fewer would find satisfaction in building infrastructure rather than using tools.

I've worked outside the FP community all my life. Functional programming is a tool, not a (monadic) religion. (And why are monadic and nomadic so similar?) Why join the community now, when the benefits are unclear and the costs palpable?

​The technical response is what I call the Latin strategy: making Ooloi's core a stable foundation for a plugin ecosystem. Build the architectural core once in Clojure, then let developers in other JVM languages contribute via plugins without needing to understand the underlying functional implementation. I've written about this approach in Penitenziagite!, so I won't rehearse it here.

Elektra's tragedy is total consumption by purpose. She becomes nothing but the task, and when it completes, there's nothing left because she permitted no existence beyond vengeance. She dances herself to death.

I'm certainly not doing that. Ooloi is a project, not my entire existence. Sustainable completion means finishing the backend, documenting it clearly, releasing it, and then moving on. The work stands independently; I remain separate from it.

I'll finish Ooloi's core architecture working alone, not because I prefer isolation, but because collaboration at this intersection point is impractical. The resolve comes from accepting reality rather than pretending community exists where it doesn't.

The backend is complete. The transducer-based timewalker is fast, tight, and efficient. Endpoint resolution handles slurs and ties correctly. Nearly nineteen thousand tests pass. Vector Path Descriptors enable elegant client-server communication.

Then comes plugin architecture, and seeing whether anyone finds Ooloi useful. If they do, excellent. If they don't, I built something architecturally sound and learned what I needed to learn.

Either way, the work speaks for itself. And I continue existing beyond it.

Nun denn, allein!

​In Umberto Eco's The Name of the Rose, a mad monk wanders through the monastery corridors shouting 'Penitenziagite!' – corrupted Latin mixed with vernacular, incomprehensible noise that might be prophecy or might be madness. Communication fails not from lack of content, but from linguistic confusion. The message is lost in translation.

Software architectures shout 'Penitenziagite!' constantly, and we've grown so accustomed to the noise that we mistake it for communication.

​When you write a plugin for a system, you shouldn't need to learn the implementation language. That seems obvious, yet most software makes exactly that demand. Functional programming libraries leak monads into Java APIs. Object-oriented frameworks force functional concepts into awkward method chains. Every language boundary becomes a barrier, every abstraction a translation exercise.

The pattern is familiar:

• Methods that expose internal implementation details externally
• APIs that assume you think in the framework's paradigm
• Documentation that requires understanding the core's language to extend the edges
• Forced mental context-switching when crossing boundaries
• 'Just learn our language' presented as the solution rather than the problem

This isn't malice. It's accidental linguistic imperialism – systems that never considered the difference between internal precision and external accessibility.

​The core cannot compromise. If mutability seeps in, if temporal coordination is abandoned for convenience, the whole thesis fails. The hard problems must be solved correctly, once, in the protected centre.

But the perimeter cannot be closed. If only Clojure developers can extend Ooloi, adoption remains limited to those willing to learn functional programming. The architectural advantages – provable speedup on reflow operations, proper concurrent editing, elimination of state-corruption bugs – must be accessible without requiring conversion.

This isn't architectural fussiness. It's the difference between a system that proves functional programming solves these problems and one that merely claims it whilst forcing everyone through the same narrow gate.

Consider the alternative: most cross-language projects either compromise the core's purity to make external access easier, or maintain purity whilst making extension nearly impossible. Both approaches fail – the first produces unreliable systems, the second produces unused ones.

​When I say plugins are first-class citizens, I mean it precisely:

• Full API access: Plugins can do anything internal code can do
• No performance penalty: JVM interop means native speed across boundaries  
• Equal capabilities: The implementation language determines developer experience, not power
• Designed from the start: The architecture was built with plugins as equals, not added later

Your Java plugin implementing custom layout rules operates with the same capabilities as Clojure core code. The boundary is invisible – just clean interfaces and reliable contracts.

Work continues: the monastery's standards hold. The architecture neither shouts incomprehensibly nor demands conversion. There's no Inquisition burning engraving monks at the stake.

The point isn't piety; it's architecture that stays intelligible.

Just clarity, properly structured.

– William of Baskerville

There are days in Ooloi’s development when I feel like the Donald. Not that Donald. Donald Knuth. There's something very real to that comparison, even though it can be seen as presumptuous. Why do I compare myself with a computing giant?

Knuth faced typesetting systems that were brittle, ad hoc, and incapable of scaling to real demands. He didn’t patch; he rebuilt the foundations. Out came deterministic algorithms, the box–glue model, and a system that still sets type decades later.

I’m in a similar place. Music notation software has been compromised for forty years: mutable object graphs, procedural hacks, import/export traps. It works until you open Eine Alpensinfonie or Lontano – then it collapses.

So Ooloi is built the way TeX was:

• Foundations first. Ooloi has been in development for a year, part-time. No notes have appeared on screen yet, but that isn’t delay, it’s sequence. The first phase was concurrency, traversal, contracts: all the invisible machinery that must be right before visible music can exist.
• Immutability as discipline. Where TeX used deterministic boxes and glue, Ooloi uses persistent data structures and STM. Both eliminate state leakage as a class of bugs.
• Correctness as architecture. In TeX, line-breaking is provably optimal. In Ooloi, sharing and traversal are mathematically guaranteed by immutability and functional design.

And even a year isn’t slow, considering what's been implemented in that time. In Clojure, as in Lisps generally, progress is faster, not slower, because the language doesn’t get in the way. Architectural changes that would take months in procedural or OO systems collapse into days when immutability is the default. In Lisps I feel unrestricted from the usual … bullshit.

​I'm one of the world's most committed anti-religious people. Despite decades at organ consoles in churches and cathedrals, I stand with Hitchens: religion is humanity's adolescent phase, something we need to outgrow. Its influence is fundamentally harmful.

But when I read something like How Lisp Became God's Own Programming Language, I completely understand the reverence the author describes. There's something about Lisp – and Clojure – that creates what you can only call a transcendental response. Nothing actually transcendental happens, of course, but the feeling is real.

What Lisp gives you is freedom. I've written about 'windsurfing through parentheses' before, and the metaphor sticks because it captures something essential. Most programmers are chained to the oars of enterprise slave galleys, with CTOs yelling 'RAMMING SPEED!' like that brilliant scene from Ben-Hur. Meanwhile, those of us who've found Lisp are windsurfing in circles around them, enjoying a freedom they can barely imagine.

The discovery feels like Dave Bowman meeting the monolith: 'My God... it's full of stars!' That vertigo when you realise this thing's inner dimensions vastly exceed its outer ones. Lisp isn't transcendental, but it works like a star gate in both senses. The language doesn't get in your way, and it opens new ways of thinking. At the same time, it's so simple that complexity becomes manageable.

I remember that August 1979 BYTE magazine perfectly. The cover promised mysteries, the articles delivered. I couldn't wait to start implementing what they described – eventually doing it in 6502 assembler, using an assembler I'd written in BASIC.

Everything clicked, even as a teenager. This was real freedom, expressed as code.

Years later, I wrote HotLisp (or 'HotLips' – M.A.S.H. was huge then) for the Royal College of Music in Stockholm. It was incredibly ambitious: a full Common Lisp that treated MIDI events as first-class citizens. Looking back, I see this as the beginning of what became Igor Engraver – integrating music directly into the computational core. We used it to control our Synclavier and MIDI synths whilst teaching algorithmic composition to advanced students at the Royal Academy.

The Two-Bit History article nails something important about Lisp's mystique. It traces the evolution from McCarthy's 'elegant mathematical system' through AI research, Lisp machines, and SICP's role in making it the language that 'teaches you programming's hidden secrets'. Each phase built the reputation.

What the article doesn't cover is the educational betrayal that followed. Computer science departments got it right for a while – they taught Scheme as a first language because it let students focus on learning algorithms rather than wrestling with syntax. Pure freedom to think about problems. Then Java Enterprise was foisted upon the world, the departments caved in, and they started churning out galley slaves instead of computer scientists. I see this as nothing short of high treason.

But here's what really matters: that freedom has evolved in Clojure. Rich Hickey didn't just bring Lisp to the JVM – he solved problems that even Common Lisp couldn't handle elegantly. Those immutable data structures aren't academic toys; they're game changers that eliminate whole categories of bugs whilst making concurrency and parallelism natural instead of terrifying. The effects ripple out: undo/redo becomes trivial, and the JVM gives genuine multi-platform reach.

This isn't just improvement – it's architectural breakthrough disguised as evolution. Clojure keeps Lisp's essential quality (that feeling of discovering how programming should work) whilst solving modern problems McCarthy couldn't have anticipated.

The poor souls in corporate Java shops keep rowing, occasionally granted small mercies as functional concepts trickle in – hints of the freedom they're missing.

I wish they could experience what we know: programming doesn't have to feel like industrial labour. There's a way of working where ideas flow directly into code, where the language becomes transparent, where you stop fighting tools and start windsurfing through solutions.

Maybe that's the point. As McCarthy noted in 1980, Lisp survives not because programmers grudgingly accept it as the best tool for each job, but because it hits 'some kind of local optimum in programming language space'. It endures even though most programmers never touch it, sustained by reports from those who've experienced its particular form of computational enlightenment.

Until we can imagine God creating the world with some newer language – and I doubt that day is coming soon – Lisp isn't going anywhere.

Read the full article at Two-Bit History: https://twobithistory.org/2018/10/14/lisp.html

Musical scores are full of repetition. In a symphony, middle C can appear thousands of times, quarter notes dominate, and the same staccato mark is scattered across every instrument. Most notation software allocates a separate object for each of these occurrences. That means thousands of identical objects, all taking memory and I/O bandwidth for no reason.

Ooloi doesn't.

With ADR-0029, we have implemented selective hash-consing: identical immutable musical objects are represented by the same instance. The same C4, the same staccato, the same quarter note: one object, shared system-wide.

Finishing the statistics infrastructure naturally led to thinking about the next architectural milestone: the rendering pipeline. This is the mechanism that determines what happens when someone clicks into a score to add a note, and how that change propagates through the system.

The design is complete. That in itself is an important milestone, as this is the very foundation on which Ooloi's performance ultimately depends. Everything hinges upon it.

Traditional notation software recalculates entire scores when a single element changes. Dense passages in works like Strauss's Elektra bring systems to a halt because every operation is sequential and single-threaded. The reason for this is that parallelism is very difficult to do with mutable state, which is the traditional approach. Scalability often becomes an issue, with diminishing returns as a result.

Ooloi takes the opposite approach and chooses the Clojure way instead, with immutable state. With this, it is comparatively easy to distribute formatting work across all available CPU cores and use them fully and linearly.

Every user action – whether adding a single note or adjusting spacing – thus becomes part of a coordinated cascade where each stage can run in true parallel across all available cores.
​
The goal is straightforward: responsive editing even in the heaviest repertoire.

ADR-0028 specifies the pipeline in five stages, separating connecting from non-connecting elements and applying a clear fan-out/fan-in pattern.

1. Minimum Widths (Fan-out): Each measure independently calculates spatial requirements – collision boundaries only. Results are immutable and persist until the content changes.
2. Vertical Raster (Fan-in): The MeasureStackFormatter collects widths, generates result rasters, and records both minimum and ideal widths. This prepares the ground for spacing optimisation.
3. Non-Connecting Elements (Fan-out): Independent symbols – noteheads, accidentals, articulations, dynamics – are prepared in parallel. They don't need finalised atom positions.
4. Discomfort Minimisation: Iterative optimisation adjusts widths and system breaks to reduce proportional distortion. No layout changes occur after this stage. From here on, positions are fixed.
5. Connecting Elements​: Slurs, ties, beams, hairpins, and glissandi are drawn only once final positions are known. Sequential coordination ensures continuity across measures and systems.

This separation allows Ooloi to exploit parallelism where possible and enforce order where necessary.

Formatting in Ooloi is plugin-driven. Core elements such as notes and beams are implemented through the same interfaces available to extensions.
​
Plugins can participate in different stages depending on their needs:

• Spacing hook (Stage 1) for collision boundaries
• Paint hook (Stage 3) for independent elements
• Connect hook (Stage 5) for elements spanning multiple atoms

Simple articulations may use only the first two; beams may require all three. This uniform model ensures extensibility without compromising performance.

The optimisation engine measures deviation from ideal proportions across measures, systems, and pages. Improvements multiply: small gains in multiple places compound into significant overall reductions. Hard constraints such as manual breaks provide natural stopping points.
​
This replaces arbitrary iteration limits with a principled measure of quality.

Claypoole provides efficient thread-pool execution, delivering significant speed-ups over built-in Clojure parallelism. STM transactions keep operations atomic while allowing concurrency inside each stage. Cooperative cancellation ensures that rapid user input remains responsive.
​
The system treats a single user as a 'collaboration network of one'. The same infrastructure that supports multi-user editing ensures smooth interaction for individuals.

This pipeline is the structural core that should make scrolling through Elektra or Ligeti's Requiem as fluid as editing a Gnossienne by Satie.
​
The specification is complete. Implementation begins as soon as the current phase closes. Ooloi's promise of responsive, professional-scale notation depends on it.

​Scary stuff.

​Full specification: ADR-0028: Hierarchical Rendering Pipeline with Plugin-Based Formatters

Every community has its breaking point. Mine came on Clojurians when I wrote a single sentence:

'Clj-kondo can go away – I have 18,000 tests'.

That was enough to get my post deleted. Before the deletion, there was 'discussion' – if you can call it that. I was told my statement was nothing more than click bait.

The irony? The author of clj-kondo himself agreed with me.

What That Line Meant

It wasn't click bait. It was a statement of principle:

• Tests prove correctness. They're executable, falsifiable, and domain-driven.
• Linters and static analysis don't. They enforce style, not truth.
• Dynamic dispatch makes static analysis less meaningful. Ooloi's architecture relies heavily on Methodical multimethods and polymorphism throughout. Static analysis tools can't trace through runtime polymorphic calls, making their warnings less informative than executable tests that actually exercise these dynamic paths.
• When you've got 18,000 tests running clean, you don't need a priesthood of external validators telling you your code is 'unsafe'.

And I was careful to make the distinction explicit: clj-kondo is a beloved, useful tool. For most projects it adds value. It just happens to be of limited use in my project, because Ooloi's architecture is already validated at a different scale.

That nuance – acknowledging the tool's value whilst drawing boundaries around its relevance – should have been the beginning of a sober technical discussion. Instead, it was treated as provocation. The fairness itself was read as heresy.

The Culture Clash

The moderator (a 'Veteran Architect') didn't engage with the point. He reacted from the gut: pearl-clutching, dismissing, and finally deleting. Exactly the kind of gatekeeping I dissected in my article on functional programming gatekeeping.

And let me be clear: I have nothing against the Clojurians themselves. They're a knowledgeable, interested lot, often deeply engaged in technical detail. The problem isn't the community – it's the moderation culture.

The moderators behave more like a church council than facilitators of discussion. Their first instinct isn't to sharpen an argument, but to protect orthodoxy, maintain decorum, and suppress anything unsettling.

The ideal they enforce seems to be some kind of cold, robotic detachment – the lab-coat fantasy of neutrality – or perhaps the modern American obsession with never offending anyone, no matter how bloodless the discourse becomes. Either way, it enforces sterility, not clarity.

You can critique syntax sugar all day long, but question a community darling like clj-kondo – even whilst calling it useful and respected – and suddenly you're accused of trolling.

Why I Left

I didn't leave because I was offended. I left because I refuse to participate in a space allergic to honesty. If a community sees a blunt critique and immediately cries click bait – ignoring both the nuance of my post and the fact that the tool's own author agreed – it has no business in my world.

Ooloi is built on clarity, not ceremony. It's an architecture tested by 18,000 executable truths, not validated by a linter's opinion. If that treads on toes, good. Prissy people afraid of dark humour or communication nuances that wouldn't pass muster at a parish council don't belong in this project. And the same thing goes for hypocrites who say, 'We're inclusive here - as long as you're exactly like us'.

The Broader Lesson

Communities often confuse politeness for health. But real progress requires the courage to tolerate discomfort. If you need your software conversations padded with pillows, you'll never survive the weight of real architecture.

As Wednesday Addams would remind us: hypocrisy is uglier than bluntness, and dishonesty is far more offensive than a glass of gin before noon. Or, indeed, a well-placed 'fuck you'.

So I deleted my Clojurians account. Because sometimes subtraction is progress.

After a year building the backend of Ooloi with Claude, I’ve learned this:

Successful AI collaboration isn’t about creative freedom. It’s about harsh constraint.

AI will overstep. Your job is to correct it—immediately, uncompromisingly.
The friction isn’t failure. It’s the method.

Read the full piece – which I asked the AI to write in its own voice – here.

​I've been saying I'm itching to open source Ooloi, but waiting for the complete software felt increasingly artificial. The documentation tells the real story – twenty-five years of architectural evolution from Igor Engraver through AWS systems thinking to this closure in Clojure.

So here it is: the complete Ooloi documentation collection, released publicly ahead of the software itself.
What you'll find:

• Comprehensive guides teaching advanced Clojure through musical problems
• Complete architectural decision records showing our thinking
• The timewalker guide (with three Rocky Horror references, naturally)
• Real functional programming education through meaningful domain examples

This represents my attempt to walk the talk after critiquing FP drawbridge syndrome. These guides serve dual purpose: they document sophisticated music notation architecture whilst teaching functional programming concepts through examples that actually matter.

The timewalker guide alone demonstrates transducers, lazy sequences, and functional composition through orchestral score traversal. The polymorphic API guide teaches multimethods through musical type systems. The concurrency patterns show STM coordination through collaborative editing.

Twenty-five years of thinking, distilled into something that I hope proves useful beyond music software. The architecture is complete; the foundations are solid. Now you can see why I've been eager to share this work.

An organism evolved, indeed.
​
Explore the complete documentation: https://github.com/PeterBengtson/Ooloi-docs

​/Peter

Now that the backend engine is complete, architecturally speaking, I'm getting increasingly eager to open the source. Itching, in fact. But as that will take a while, the least I can do for you is give you the WELCOME.md file from the source repo. 

​/ Peter

I found myself confronting what appeared to be a deceptively simple requirement for Ooloi: 'Resolve slur endpoints across the musical structure'.

Rather straightforward, one might assume: simply traverse the musical structure and locate where slurs terminate. But then, as so often is the case, the requirements revealed added complexity:

• Slur endpoints must be discovered in temporal order (measure 1 before measure 2, naturally)
• Yet slurs can span multiple voices on the same staff
• Or cross between neighbouring staves within an instrument
• And precisely the same temporal traversal logic would be required for MIDI playback
• Not to mention visual layout calculations and formatting
• And harmonic analysis
• And collaborative editing conflict resolution

​Allow me to demonstrate the pattern I anticipated avoiding. Without a general traversal utility, each application would require its own approach:

Three functions, identical traversal logic, different transformations. Exactly the architectural smell I wanted to avoid from the outset.
​
This was precisely Rich Hickey's transducer insight made manifest: "What if the transformation was separate from the collection?"

​What if I could write the temporal traversal once, then apply different transformations to it?

Objective achieved: one traversal algorithm, many applications.
​
But its architectural reach turned out to be even more profound.

The design decision hinged upon recognising that I was conflating two distinct concerns: the mechanism of traversal and the logic of transformation. This wasn't merely about avoiding the tedium of duplicated code (though that would have been reason enough) but rather about establishing clean architectural boundaries that would serve the system's long-term evolution.

Consider the conceptual shift this separation enabled:
​
Rather than thinking in terms of specific operations upon musical structures:

• 'I need to find slur endpoints in this piece'
• 'I need to generate MIDI from this piece'
• 'I need to calculate layout from this piece'

The transducer approach encouraged thinking in terms of composed processes:

• 'I need to traverse this piece temporally, then apply endpoint filtering'
• 'I need to traverse this piece temporally, then apply MIDI transformation'
• 'I need to traverse this piece temporally, then apply layout transformation'

The traversal thus became reusable infrastructure, whilst the transformation became pluggable logic. This distinction would prove invaluable as the system's requirements expanded.

​What I hadn't anticipated was how broadly applicable the resulting abstraction would prove. After implementing the piece-walker for attachment resolution, I discovered it elegantly supported patterns I hadn't originally considered, each demonstrating the composability that emerges naturally from separating traversal concerns:

​Each is built from simple, testable pieces. And they all inherit the same temporal coordination guarantee. This composability emerged naturally from the transducer design: a pleasant architectural bonus.

As one would expect from a well-designed transducer, memory usage remained constant regardless of piece size: a particularly crucial consideration when dealing with the sort of orchestral scores that might contain hundreds of thousands of musical elements.
​
Consider the alternative approach, which would create intermediate collections at each processing step:

​The transducer version processes one item at a time:

​Same result, constant memory usage. This exemplifies what Rich meant by 'performance without compromising composability'.

Transducers suffer from an unfortunate reputation for complexity, often relegated to 'advanced topics' when they needn't be. This is particularly galling given that they're fundamentally straightforward when you encounter the right use case, which the musical domain provides in abundance.
​
Think of transducers as 'transformation pipelines' that work with any data source, much as one might design AWS data processing workflows that operate regardless of whether the data arrives from S3 buckets, database queries, or API streams:

The pipeline stays the same. The data source changes.
​
In Ooloi:

The piece-walker solved a universal software problem: How does one avoid duplicating traversal logic whilst maintaining performance and composability?

This pattern applies everywhere:

• Web scraping: Same page traversal, different data extraction
• Log analysis: Same file reading, different filtering and aggregation
• Database processing: Same query execution, different transformations
• Image processing: Same pixel iteration, different filters

Transducers provide the infrastructure for "traverse once, transform many ways."

Building the piece-walker demonstrated that transducers aren't an abstract functional programming concept. They're a practical design pattern for a specific architectural problem: separating the concerns of traversal from transformation.

The musical domain made this separation particularly clear because the temporal coordination requirements are so explicit. When you need the same traversal logic applied with different transformations, transducers provide the elegant answer.
​
This separation makes code:

1. More testable (test traversal and transformations independently)
2. More reusable (same traversal, different applications)
3. More maintainable (one place to optimise traversal performance)
4. More composable (mix and match transformations)

The piece-walker is documented thoroughly in our Architecture Decision Record for those wanting technical details. But the real value lies not in the musical specifics but in observing how transducers address genuine architectural challenges with apparent effortlessness.

The next time you find yourself contemplating similar data processing logic across multiple contexts, you might ask: 'What if the transformation was separate from the collection?'
​
You may well recognise your own perfectly suitable transducer use case.

I recently spotted a meme on LinkedIn featuring a brooding, aristocratic Dracula asking, "What is a monad but a monoid in the category of endofunctors?" – accompanied by no explanation whatsoever. I chuckled, as one does when recognising an in-joke, but then found myself pondering a rather uncomfortable question: Is this really how we want to present functional programming to the world?

The Allure of the Arcane

There's something undeniably satisfying about mastering difficult concepts. When I first grasped the elegant power of immutable data structures, higher-order functions, and composability, it felt like discovering a secret door in a familiar house – one that led to a vast, beautiful landscape I'd never known existed. That eureka moment is profound, even transformative.

But here's the rub: why do we in the functional programming community so often present that door as if it requires an arcane ritual to unlock? Why do we seem to relish the impenetrability of our terminology?

Let's be honest with ourselves. There's a whiff of intellectual snobbery in the air when functional programmers gather. We've all heard (or perhaps even made) the disparaging remarks about "Java drones" or "code monkeys churning out mutable state on corporate slave galleys". We swap stories about the moment we "finally understood monads" as if recounting our initiation into a secret society. We wear our hard-won knowledge as a badge of honour – and sometimes, if we're being truly honest, as a mark of superiority.

The Hidden Cost of Exclusivity

This exclusivity comes at a cost. Functional programming remains woefully underutilised in the industry at large, despite offering compelling solutions to many of the problems that plague software development. Concurrency, side effect management, robust testing, code reuse – these aren't niche concerns, they're central challenges in modern software engineering. Yet we've somehow managed to position our toolbox of solutions as if it's too rarified for everyday use.

Consider the meme I mentioned. For the initiated, it's a humorous reference to a famously opaque definition. For everyone else, it's not just impenetrable – it actively signals that they don't belong in the conversation. It's a velvet rope strung across the entrance to a club they didn't even know they might want to join.

I'm reminded of my journey from Common Lisp to Clojure. Both languages offer powerful functional paradigms, but Clojure has managed to achieve something remarkable: it has brought functional programming concepts to a significantly wider audience. It didn't accomplish this by watering down the functional paradigm, but by emphasising practicality alongside purity. By meeting developers where they are – on the JVM, with access to the libraries and tools they already know – Clojure created an on-ramp rather than a barrier.

No Monads Required

Here's something we don't acknowledge often enough: you don't actually need to understand monads to be a productive functional programmer. In fact, in languages like Clojure, you can write elegant, powerful functional code for years without ever encountering the term. The core principles of functional programming – immutability, pure functions, higher-order functions, composability – can be understood through practical examples without diving into category theory.

This isn't to say that the deeper theory isn't valuable. Of course it is! The mathematical foundations of functional programming provide extraordinary insight and power. But they're not the entrance exam. They're advanced courses you can take once you're already enrolled.

Yet somehow, we've allowed the most theoretically complex aspects of functional programming to become its public face. It's as if we're advertising a car based on its differential equations rather than where it can take you.

The False Dichotomy

There's an insidious implication lurking beneath this state of affairs: the notion that there are two classes of programmers – the enlightened few who grasp the elegant abstractions of functional programming, and the unwashed masses writing imperative code. This is, to put it bluntly, utter bollocks.

The reality is far more nuanced. Most programmers exist on a spectrum of understanding and application of functional principles. Many Java developers make excellent use of streams and lambdas. JavaScript programmers increasingly embrace immutability and pure functions. Even in traditionally imperative contexts, functional patterns are gaining traction.

These aren't "lesser" applications of functional programming – they're pragmatic adaptations that solve real problems. The senior developer who introduces Option types to avoid null pointer exceptions in a legacy Java codebase is applying functional thinking in a way that delivers immediate, tangible benefits. Should we really consider them less enlightened than someone who can recite the monad laws but has never shipped a product?

Building Bridges, Not Walls

If we truly believe in the benefits of functional programming – and I certainly do – then we should be building bridges to make these ideas more accessible, not walls to keep the uninitiated out.
​
What might this look like in practice?

For starters, we could focus our evangelical efforts on the practical benefits rather than the theoretical foundations. When I'm talking to a team about adopting Clojure or functional patterns, I don't open with category theory. I talk about dramatically reduced bug rates due to immutability. I show how composable functions lead to more reusable code. I demonstrate how side effect isolation makes testing simpler and more reliable. And to really wow them, I might describe how immutable data structures instantly solve the Undo/Redo problem for any application with a frontend.

We could also acknowledge that functional programming isn't an all-or-nothing proposition. Encouraging teams to adopt functional patterns incrementally within their existing codebases can yield substantial benefits and build confidence for deeper adoption. The choice isn't between pure Haskell and imperative spaghetti code – there's a vast, productive middle ground.

Most importantly, we need to shift our community culture away from exclusivity and toward inclusivity. This doesn't mean abandoning rigour or depth – it means recognising that everyone starts somewhere, and the journey from imperative to functional thinking is challenging enough without adding artificial barriers.

The Clojure Case Study

It's worth examining why Clojure has been relatively successful in attracting developers who might otherwise have been put off by functional programming's reputation for difficulty.

Firstly, Clojure is pragmatic to its core. It embraces functional principles without dogmatism, allowing for controlled mutability when necessary. It prioritises solving real problems over theoretical purity.

Secondly, it meets developers where they are. By running on the JVM (and later JavaScript engines), it allows gradual adoption and interoperability with existing systems.

Thirdly, and perhaps most importantly, the Clojure community has generally focused on what the language enables rather than how clever you need to be to use it. The emphasis has been on what you can build, not on arcane knowledge as a status marker.

This approach hasn't compromised the language's functional credentials – Clojure remains thoroughly functional in its philosophy and implementation. But it has made those functional principles accessible to a much wider audience.

A More Welcoming Future

I'd like to see a functional programming community that celebrates bringing new people in rather than keeping them out. One that takes as much pride in making complex concepts accessible as it does in mastering them.

Imagine if our response to someone struggling with functional concepts wasn't "Well, once you understand monads..." but rather "Here's how this approach solved a similar problem I had..."

Imagine if we shared our enthusiasm not through insider references that exclude the uninitiated, but through concrete examples that demonstrate the real-world power of functional approaches.

Imagine if we recognised that the true measure of our understanding isn't our ability to recite category theory, but our ability to apply these principles to build better software and help others do the same.

As I continue to develop Ooloi, my open-source music notation project in Clojure, I'm constantly reminded of this tension. The functional paradigm allows me to build a system that's both powerful and elegant. The code is concise, composable, and expressive in ways that would be difficult to achieve with imperative approaches. But when I'm documenting the system or preparing it for open-source collaboration, I'm mindful of the need to make these concepts accessible.

The goal isn't to water down the functional aspects – they're essential to the system's design. Rather, it's to provide on-ramps that allow developers to engage with these ideas gradually, to see their practical benefits before diving into the deeper theory.

Conclusion

Functional programming isn't a secret to be jealously guarded – it's a powerful set of tools that can dramatically improve how we build software. Its core insights deserve to be widely shared and applied.

​So the next time you're tempted to share that monad joke or category theory reference, ask yourself: Am I opening a door or closing one? Am I inviting others to share in something valuable, or am I simply signalling my own cleverness?

We don't need gatekeepers in the functional programming community. We need guides. Guides who remember what it was like not to know, who can explain complex concepts in accessible terms, who take pride not in how exclusive their knowledge is but in how effectively they can share it.
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After all, what is a community but a group of people helping each other grow?