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#009 · · 1:50 Ruby's safe navigation operatorelbcastsprogramming tutorialscreencastRuby

Ruby's Safe Navigation Operator

Ruby's safe navigation operator

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#00916 Oct 2026Ruby's safe navigation operator · elbcasts · programming tutorial · screencast · Ruby

Ruby's Safe Navigation Operator

Ruby's safe navigation operator
7:01
#00815 Oct 2026AI agents · ai coding agents · claude code · codex · elbcasts · git worktree · multi-agent · openmausbot · programming tutorial · ruby on rails · screencast · Chief of Staff · parallel AI agents · claude code tutorial · codex cli · ai pair programming · tdd with ai · rails 8 · OpenMausBot · MausBot

I Let 3 AI Agents Build a Rails Feature. Here's What Broke

I ran Claude Code and Codex in parallel on one Rails ticket, with a coordinator writing the failing tests first. Here's what broke, what it cost, and when one session beats a team.
4:37
#00714 Oct 2026OpenMausBot AI bots · ai agents · ai bots · claude code · elbcasts · grok bot alternative · local ai · multi-agent · open source · openmausbot · programming tutorial · screencast

OpenMausBot: your own team of AI bots

These release notes cover seven commits — and I didn't write them. An AI bot did, on my own machine, in about a minute. And before it ran a single command, it asked me.
4:58
#00613 Oct 2026AI for developers · Risk decisions with a local model · active job · decision thresholds · elbcasts · fraud detection · human in the loop · laya · local ai · programming tutorial · rails · screencast · turbo streams

I set my AI fraud threshold to 0.98. It paid out nothing

I set my AI fraud threshold to 0.98 because it felt safe — and it paid out nothing. Zero. Here's how to route risky decisions three ways (pay out, block, ask a human) and read...
5:13
#0056 Oct 2026AI for developers · Measuring decision models · elbcasts · github issues · jev · laya · llm evaluation · local ai · programming tutorial · python · ruby · screencast · typesafe ai

Don't trust the model card: three decision models on real data

After this episode the viewer can measure any classification model on their own labelled data in twenty lines, and use the probability to decide what runs without a human.
4:16
#0041 Oct 2026Rails Turbo Streams · Ruby on Rails · action cable · broadcasts_to · elbcasts · hotwire · programming tutorial · rails · rails 8 · realtime · screencast · solid cable · turbo streams

Rails Turbo Streams from a Background Job (No JavaScript)

After this episode the viewer can push a change from a background job straight into an open page with Turbo Streams and Solid Cable, and knows why the async adapter never works...
4:26
#00326 Sep 2026Rails Background Jobs with Solid Queue · Ruby on Rails · active job · background jobs · elbcasts · perform_later · programming tutorial · rails · rails 8 · retry_on · screencast · solid queue · sqlite

Your form waits three seconds — move it to a job (Solid Queue)

After this episode the viewer can move slow work out of the request into an Active Job, run it with Solid Queue in development, and know where jobs get lost.
5:11
#00223 Sep 2026Rails Form Objects · Ruby on Rails · activemodel · elbcasts · form objects · programming tutorial · rails · rails 8 · rails forms · refactoring · screencast · strong parameters · thin controller

Stop Fat Controllers: Rails Form Objects Explained

After this episode the viewer can build a form that spans two models with a plain Ruby form object, keep validations in one place, and keep the controller thin.
5:02
#00121 Sep 2026rails uniqueness validation · validates uniqueness rails · rails normalizes · rails unique index · rails duplicate records · rails race condition · activerecord validations · rails model validations · rails form errors · postgres unique index · postgresql constraints · data integrity · rails 8 · activerecord · ruby on rails tutorial · ruby on rails · postgres · web development

Your Rails uniqueness validation won't stop duplicates

After this episode the viewer can stop bad data at the model with validates and normalizes, show the errors in the form, and back the rule with a database index.