Rails 8.2 Callbacks and Background Jobs in Production
Rails 8.2 and Ruby 4.0 expose hidden callback costs. Learn why callbacks fail in production and what to use instead.
1 min read
Ruby & Rails Core
Core language and framework features, Rails 8.1 updates, Ruby 3.4 improvements
Upgrading to Rails 8.2 Without Downtime
A production-tested playbook for upgrading to Rails 8.2 with Ruby 4.0. Avoid downtime, lockups, and silent performance regressions.
2 min read
Rails 8.2 Concurrency: Why Your App Is “Thread-Safe” but Still Slow
Rails 8.2 is thread-safe but still slow under load. Learn how Ruby 4.0 exposes connection pool starvation and how to fix concurrency correctly.
4 min read
Rails 8.2 Active Record Changes That Break at Scale
Rails 8.2 changes Active Record behavior in ways that hurt performance at scale. Learn what breaks, how Ruby 4.0 exposes it, and how to fix it safely.
4 min read
LEFT JOIN + WHERE in ActiveRecord: The Trap That Turns It Into INNER JOIN
Fix Rails LEFT JOIN + WHERE trap that becomes INNER JOIN. Covers .left_joins, scoped associations, WHERE vs ON, and SQL verification with examples.
5 min read
Ruby 4.0.0 Is Out: What Rails & ActiveRecord Devs Actually Need to Know
Ruby 4.0.0 is released (Dec 25, 2025). For Rails apps, the real risks are stdlib gem changes (CGI), Net::HTTP behavior shifts, and Bundler 4. Here’s what breaks first, how to fix safely, and what Ruby 4 performance does—and doesn’t—solve.
6 min read
N+1 Isn’t a Rails Problem: It’s a Query-Shaping Problem
Copied SQL into Rails and still got N+1? Rewrote in ActiveRecord and still got N+1? The fix is a set-based mental model: where N+1 really comes from, how to verify it, and the AR patterns that eliminate it safely.
5 min read
Why ActiveRecord Exists: The SQL Mental Model That Breaks in Rails
If you know SQL, ActiveRecord can feel pointless—until it saves you from consistency bugs. Here’s the mental model: where SQL alone breaks app invariants, and how to use AR without losing performance.
5 min read
Modular Monoliths in Rails 8.1 with Engines: Boundaries Without Microservices
A production-minded guide to building a modular monolith in Rails using Engines: where boundaries usually leak, how to structure code, and the upgrade-safe patterns that prevent cross-domain coupling.
6 min read
Rails 8.1 Devcontainers for Teams: Stop Setup Drift
A production-minded Rails 8.1 devcontainer setup that standardizes Ruby, Node, Postgres, and tooling across a team—plus the real failure modes and how to avoid them.
4 min read
Ruby 3.5 Preview: What Matters for Rails in Production
Ruby 3.5 was released as a preview; Ruby 4.0 shipped. Here’s what actually matters for Rails apps: what won’t change, what can break, and where SQL/ActiveRecord fixes beat runtime upgrades.
4 min read
Rails 8.2 Preview: What Production Apps Actually Gain in 2026
A production-focused preview of Rails 8.2 explaining real-world impact on caching, TypeScript integration, Turbo behavior, and upgrade risks.
3 min read