Designing software systems and thinking about why most of them hurt. Rails, JavaScript, architecture, product. https://syedaslam.comhttps://bsky.app/profile/syedaslam.bsky.socialhttps://bsky.app/profile/syedaslam.bsky.social/post/3mkfcpl7bis2oRails routing isn’t smart. It’s deterministic. It matches a request against your route set, in order, and dispatches to the first match. That single idea explains most routing “mysteries.” Wrote a breakdown of how it actually works: https://open.substack.com/pub/railsrevelry/p/how-rails-routing-works-turning-urls?r=4jsb&utm_medium=ios26 Apr 2026 10:07 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mkfcpl7bis2ohttps://bsky.app/profile/syedaslam.bsky.social/post/3mkdxhytxys2gNew article: Inside the Rails middleware stack. The core idea: middleware is not a checklist before your controller. It is a chain of Rack wrappers around your app. That explains sessions, redirects, headers, and why some requests never reach your controller. https://open.substack.com/pub/railsrevelry/p/inside-the-rails-middleware-stack?r=4jsb&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true25 Apr 2026 21:13 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mkdxhytxys2ghttps://bsky.app/profile/syedaslam.bsky.social/post/3mjrgqbgeh22oI’ve been wanting to write more about how Rails actually works under the hood, not just how to use it. So I started RailsRevelry. Explaining what really happens between an HTTP request hitting your app and your controller action running. https://railsrevelry.substack.com/p/from-rack-to-controller-understanding18 Apr 2026 12:26 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mjrgqbgeh22ohttps://bsky.app/profile/syedaslam.bsky.social/post/3mjhn7xm7k22tUnderstanding the dependency, execution, and behavioral surfaces of a Rails system makes upgrades more predictable. https://syedaslam.com/posts/a-preflight-for-rails-upgrades/14 Apr 2026 14:55 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mjhn7xm7k22thttps://bsky.app/profile/syedaslam.bsky.social/post/3mjd6jqkx2k2bhttps://open.substack.com/pub/railsrevelry/p/from-rack-to-controller-understanding?r=4jsb&utm_medium=ios&shareImageVariant=split12 Apr 2026 20:22 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mjd6jqkx2k2bhttps://bsky.app/profile/syedaslam.bsky.social/post/3milybldgl22pA Rails upgrade rarely fails because of Rails. It fails because of everything the system has accumulated around it. Dependency graph Runtime Infrastructure Hidden behavior The version bump is just where the failure shows up. https://syedaslam.com/posts/the-signals-that-predict-a-difficult-rails-upgrade/03 Apr 2026 14:59 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3milybldgl22phttps://bsky.app/profile/syedaslam.bsky.social/post/3mi4u6doay22gI maintain a small Ruby gem called duration_in_words, and I just shipped v0.3.1. It formats ActiveSupport::Duration values like 1.day + 2.hours + 30.minutes into readable strings, with locale-aware output and better pluralization support. https://github.com/aslam/duration_in_words28 Mar 2026 14:35 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mi4u6doay22ghttps://bsky.app/profile/syedaslam.bsky.social/post/3mhptd3pzoc2gRails upgrades don’t become painful because teams get unlucky. They become hard in predictable ways. The curve: low friction -> rising friction -> avoidance -> recovery. The mistake is treating upgrades as execution work. They’re discovery problems first. https://syedaslam.com/posts/the-upgrade-anxiety-in-mature-systems/23 Mar 2026 10:15 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mhptd3pzoc2ghttps://bsky.app/profile/syedaslam.bsky.social/post/3mgula6ehnk2yOne of the quiet constraints of software systems is something we rarely talk about explicitly: Every codebase has a local reasoning budget. When the budget is exceeded, the experience changes dramatically. https://syedaslam.com/posts/the-local-reasoning-budget-of-a-codebase/12 Mar 2026 14:09 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mgula6ehnk2yhttps://bsky.app/profile/syedaslam.bsky.social/post/3mgahdh4a5k2hGot a BSI abuse report via Hetzner: my Postgres (5432) was exposed from a Kamal/Docker deploy. root cause: port: "5432:5432" published to 0.0.0.0, and UFW didn’t protect it the way I expected. fix: bind to localhost (127.0.0.1) + verify secrets handling in Kamal 2.x. https://syedaslam.com/posts/why-the-german-government-emailed-me-about-my-kamal-deployment/04 Mar 2026 14:06 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mgahdh4a5k2hhttps://bsky.app/profile/syedaslam.bsky.social/post/3mfu6ugk7i22iNew post: Where Rails Apps Actually Slow Down Rails apps rarely degrade because Rails is slow. In long-lived systems, the usual causes are hidden query multiplication, layered indirection, and caching masking hot paths. Performance tuning is often visibility work. https://syedaslam.com/posts/where-rails-apps-actually-slow-down27 Feb 2026 17:02 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mfu6ugk7i22ihttps://bsky.app/profile/syedaslam.bsky.social/post/3mffb3unqkc2fMemoizing with ||= in Ruby looks clean and idiomatic, until your domain evolves and "false" becomes a legitimate cached value. Here's why ||= doesn't mean "if unset" (it means "if falsey"), and how that subtle distinction silently kills performance. https://syedaslam.com/posts/when-or-equals-betrays-your-memoization/21 Feb 2026 18:32 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mffb3unqkc2fhttps://bsky.app/profile/syedaslam.bsky.social/post/3mel7oekfds2wRails taught me this twice: first, callbacks made flows unclear. Then service objects did the same. The problem isn’t patterns, it’s indirection that overshadows its usefulness. I wrote about how to recognize and cut that decay. https://syedaslam.com/posts/when-good-abstractions-age/11 Feb 2026 09:58 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mel7oekfds2whttps://bsky.app/profile/syedaslam.bsky.social/post/3mdxpoho3x22tWrote a new blog post on why Stimulus works so well in mature Rails apps: https://syedaslam.com/posts/stimulus-is-boring03 Feb 2026 15:51 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mdxpoho3x22thttps://bsky.app/profile/syedaslam.bsky.social/post/3mcuacscluk2jActiveModel::Serializers (AMS) is archived, yet many Rails apps still use it. Why? Replacing your serialization layer is scary.20 Jan 2026 13:13 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mcuacscluk2jhttps://bsky.app/profile/syedaslam.bsky.social/post/3mcki5mtsec2sSometimes the best feature you can add is a constraint. By limiting what users can do, you guarantee the dignity of the content remains intact.16 Jan 2026 16:06 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mcki5mtsec2shttps://bsky.app/profile/syedaslam.bsky.social/post/3mcaah5nlps22I've spent years building software systems. Lately, I'm more interested in understanding why they hurt than adding new features. Posting thoughts as I go.12 Jan 2026 14:22 +0000at://did:plc:gn7zthmcy3uh7et4642e7qd3/app.bsky.feed.post/3mcaah5nlps22