Streamlining Web App Development With Zeroconf

The sites which are using Shardine do not only have separate data storage - they all have their own domain names. I frequently need to validate that every site is able to work correctly with the changes I am making. At Cheddar we are also using multiple domains, which is a good security practice due to CORS and...

A Can of Shardines: SQLite Multitenancy With Rails

There is a pattern I am very fond of - “one database per tenant” in web applications with multiple, isolated users. Recently, I needed to fix an application I had for a long time where this database-per-tenant multitenancy utterly broke down, because I was doing connection management wrong. Which begat the question: how do you even approach doing it right?

Template-Scoped CSS in Rails

Hot on the heels of the previous article I was asked about my idea of having co-located CSS. Now is the time to share, so read on!

A Supermarket Bag And a Truckload Of FOMO

The day was nearing to a close. The sun has already set, but that Friday evening in Amsterdam was still warm. Unusually warm, in fact, for those late days in March – as if spring decided to bless my pilgrimage, for that pilgrimage was not jovial.

I was sitting at a ramen joint, sipping on the broth. To my left,...

UI Algorithms: A Tiny Undo Stack

I’ve needed this before - a couple of times. Third time I figured I needed something small, nimble - yet complete. And - at the same time - wondering about how to do it in a very simple manner. I think it worked out great, so let’s dig in.

Most UIs will have some form of undo functionality. Now, there...

Musings on Module Registration (And Why It Could Be Better in Rails)

Having the same architecture problems over and over does give you perspective. We all love making fun of the enterprise FizzBuzz but there are cases where those Factories, Adapters and Facades are genuinely very useful, and so is dependency injection. Since I had to do dependency injection combined with adapters a wee many times now, it seems like a good...

The Surcharge of Big Tech

There is a lot of talk that big-tech companies are willing to pay way more, way up north of the market to the local rates. They all seem similar:

• Pre-IPO or public
• Looking for senior software engineers or staff engineers
• Salary brackets never published, and even recruiters stay fairly tight lipped
• So-described “transparent” interview process - usually a marathon...

Disownership, Pull Requests And De-Facto Architects

A while ago I got really triggered by by the following two tweets - one by Avdi and another by Pete

This essay was on my mind - and lying dormant - for a couple of years, but I think it didnt lose its relevance.

Supercharge SQLite with Ruby Functions

An interesting twist in my recent usage of SQLite was the fact that I noticed my research scripts and the database intertwine more. SQLite is unique in that it really lives in-process, unlike standalone database servers. There is a feature to that which does not get used very frequently, but can be indispensable in some situations.

By the way, the...

Maximum Speed SQLite Inserts

In my work I tend to reach for SQLite more and more. The type of work I find it useful for most these days is quickly amalgamating, dissecting, collecting and analyzing large data sets. As I have outlined in my Euruko talk on scheduling, a key element of the project was writing a simulator. That simulator outputs metrics...

Joke Accounts Are a Bitter Necessity

Joke Accounts and the BOFH are Garbage by Aurynn Shaw struck a chord with me back in the day. After all, who wants to exclude people? Who wants to make them feel unwelcome? Having survived some amount of difficult working experiences I have changed my mind on this drastically. The joke accounts are a bitter necessity, and I’ll try...

Reviving zip_tricks as zip_kit

Well-made software has a lifetime, and the lifetime is finite. However, sometimes software becomes neglected way before its lifetime comes to an end. Not obsoleted, not replaced - just.. neglected. Recently I have decided to resurrect one such piece of software.

See, zip_tricks holds a special place in my heart. It was quite difficult to make, tricky, but exceptionally...

Exploring Batch Caching of Trees

From my other posts it might seem that I am a bit of a React hater - not at all. React and related frameworks have introduced a very powerful concept into the web development field - the concept of materialised trees. In fact, we have been dealing with those in Rails for years now as well. Standard Rails rendering has...

Testing a Thousand Applications With Flipper

Feature flags are amazing. No, really, did I tell you that feature flags are amazing? They are. But you might be running a thousand applications. When this kind of complexity gets involved you might need to test combinations of feature flags, sometimes - dozens of those combinations. Exhaustive testing to the rescue!

Tool Complexity Might Have a Cure: Those Pesky People Who Say No

Marco Rogers started a remarkable thread on Mastodon, which absolutely struck it home for me. Teams absolutely do get mired up in complex tooling. They absolutely can be unprepared, and there absolutely is a skew between the newly-minted “frontend” and “backend” ecosystems. I might have a few things to say about this.

Your Might Be Running A Thousand Applications

Feature flags are awesome. But just like user preferences or settings they have the tendency of turning your application into multiple applications, all embedded in one.

Changing Your Mind is Not My Job

There is a popular meme that has been going around for years now, This is in fact close to heart for every passionate technologist. Most of use have either been the guy at the desk, or an innocent passer-by willing to enter the conversation. With fairly expected results.

Versioned Business Logic With ActiveRecord

Every succesful application evolves. Business logic is often one of the things that evolves the most, but it is customary to have data which changes over time. Sometimes - over months or years. A lot of spots have logic related to “data over time”. For example: you collect payments from users, but some users were not getting charged VAT. Your...

On the Value of Interfaces (and when you Need One)

It is curious how people tend to bash DDD. I must admit - I never worked in a full-on DDD codebase or on a team that practices it, but looking at the mentioned articles like this one does make me shudder a little. There is little worse than a premature abstraction, and a there is a noticeable jump (or...

UI Algorithms: Drag-reordering

A list where you can reorder items is one of entrenched widgets in UIs. Everyone knows how they are supposed to work, they are cheap to build, intuitive and handy. The problem is that they often get built wrong (not the “just grab Sortable.js and be done with it”-kind-of-wrong, but the “Sortable.js does not provide good user experience”-kind-of-wrong). I’ve built...

The Unreasonable Effectiveness of Leaky Buckets (and how to Make One)

One of the joys of approaching the same problem multiple times is narrowing down on a number of solutions to specific problems which damn work. One of those are idempotency keys - the other are, undoubtedly, rate limiters based on the leaky bucket algorithm. That one algorithm truly blew my mind the first time Wander implemented it back...

Two Other Possible Reasons Juniors are Having it Tough on the job Market

It has recently become a hot topic that junior developers are having difficulties finding a job, even though the market is very hot at the moment. Market for senior talent is, yes, but for juniors - not so much. As a matter of fact it has been flagged that it is harder than ever for a beginner to start...

Actually Creating a gem for Idempotency Keys

I’ve already touched on it a bit in the article about doing the scariest thing first – one of the things we managed to do at WeTransfer before I left was implementing proper idempotency keys for our storage management system (called Storm). The resulting gem is called idempo and you use it about like this:

The Value of not Having to be Right

In software we pride ourselves in being “data-informed”, “metrics driven”, and “formally proven” is the highest praise. Few things feel as satisfying as being actually right, with no shadow of a doubt and no way of escape for our opponents. Being tech people, we cling to this idea that “the more correct” idea, or the one which is “objectively right”,...

Art, Science, Taste and "Clean Code"

Science establishes concepts that describe nature, and is often able to signal binary answers to questions. “Can acceleration be non-0 when velocity is 0?” “What is the circumference of a circle?” “How many chromosomes does a fruit fly genome contain?”

Art, unlike science, speaks to our emotion. Great art is great exactly because - in addition to execution - it...

Do the Scariest Thing First

I know the pieces fit, cause I watched them fall apart

Kir recently wrote about fragmented prototyping which struck a nerve. I use a very similar approach for gnarly engineering and system design problems, so figured I could share while we are at it. I call it the maximum pain upfront approach. Another name could be do...