Scale Your Rails Monolith | Damián Le Nouaille

The Reality Check

Does this sound like your morning standup?

"We can't ship this yet"

"We have to push the launch by 2 weeks because we need to refactor the Billing module first. It's just too risky."

"Why is QA the bottleneck?"

"We have QA engineers manually clicking through the app because we don't trust our test suite. We are coding blind."

"Deployment is an event"

"Our pipeline takes 45 minutes. If it fails, we lose an hour. So we only deploy once a day, and never on Fridays."

"Hiring is a nightmare"

"We struggle to find Senior Rails devs. When we do, it takes 6 months of costly onboarding before they are productive."

"Design integration takes forever"

"Developers are not integrating the UI in the best possible way because they have 'more important things to do'."

The Hard Truth

You are slowing down your entire company because the tech has become the bottleneck.

Cursor and Copilot are NOT a Strategy.

Giving your developers Cursor is like giving a faster car to a driver stuck in gridlock. It helps them type faster, but it doesn't fix the traffic jam (your architecture).

You need Repo-Level Agents.

Your competition is already figuring this out. By Q2 2026, the winning companies will have automated their maintenance. They will be shipping features while you are still debugging a Gemfile.lock conflict.

The Old Way

Throw more humans at the problem

Linear cost, logarithmic output. More meetings, more complexity.

Recommended

The New Way

Build AI Assets that scale

Fixed cost, exponential output. Agents work while your team sleeps.

The Agent Arsenal

Building the machine that builds the code. A suite of specialized agents for every bottleneck.

The Rails Upgrader

Rails 6 → 7 → 8. Handles breaking changes, `zeitwerk` loading issues, gem dependency hell, and configuration updates.

The Test Expander

Custom Fuzzing Agent running thousands of scenarios. Finds edge cases between "Prod Data" and "Test Data".

The i18n Cleaner

Extracts raw strings from views, creates clean i18n files, and scans for unused keys to keep translations tidy.

The PR Reviewer

Fine-tuned on your git history. Comments with context: "We use Service Objects for this logic, not concerns."

The Legacy Killer

Points at the "Dark Zone". Refactors God Objects into discrete Concerns and Services with safety tests.

The Documentation Master

Auto-updates docs based on code. Creates visuals and schemas. Drops onboarding time from 2 weeks to 2 days.

The Performance Optimizer

Scans production logs to optimize most used routes and background jobs for immediate user impact. Tackle slow SQL queries, spot the N+1, and reduce memory bloat.

The Feature Planner

Creates detailed reports on files to modify for new features, pinpointing risks and implementation steps.

The Design Integrator

Integrates the Figma design into the views. Faster than ever before.

The "Guardian" Retainer

Protecting the Asset after the initial sprint.

Weekly dependency upgrades (no more Big Bangs)
Continuous Agent retuning on new patterns
Emergency Triage (bugsnag/sentry analysis)

Implementation Timeline

12-18 Days

From quote approval to final agents review.
Typical audit takes 3 days.

Case Study: FinTech Scale-Up (Series B)

Real-world metrics

Metric

Before Optimization

After Agent Implementation

Rails Version

Before 6.0 (EOL Risk)

After 7.2 (Stable) Prepared for 8.0

Test Suite Duration

Before 42 minutes (Flaky)

After 9 minutes Reliable

Test Coverage

Before 65% Critical paths missing

After 94% Agent-generated edge cases

Deploy Frequency

Before 2x / Week

After 8x / Week

"Bug" Tickets / Sprint

Before ~12

After ~2

The Math of Automation

Assumptions: Senior Dev Cost = $110/hr (Salary + Overhead).

Status Quo Cost

$528k/yr

If you have 10 developers losing 30% of their time to "The Grind" (waiting for CI, fixing regressions, manual refactoring), you are burning half a million dollars just to keep the lights on.

Projected Savings

$264k/yr

I target a 50% reduction in this friction.

Plus the immeasurable value of shipping your Q3 roadmap in Q2.

You can go way above this number depending on your team and your stack. I've seen teams going 2x faster while improving the stability of the application in less than a month.

Zero-Risk Integration

I interface with your team like an external contractor, but powered by a fleet of agents.

Pull Requests Only

I never commit directly. You review everything.
Sandboxed Environment

Agents run in CI (or locally), not on your production server.
Human-in-the-Loop

I provide the architecture; you provide the green light.
Team Training

I teach your team how to use these new agents.

Input

Your Repo

Processing

Agent Sandbox

Refactor • Test • Document

Output

Clean PR

I am a Solo Principal Operator.

I don't have a sales team. I don't outsource to juniors.
You are hiring 15 years of battle scars and deep mastery of the modern AI stack. You talk directly to me.

If you want to learn more about me, you can check my story here:
Read my story.

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New Message

To:

Subject: Need Rails AI Agents for our Rails app

Hi Damian,

I am [Your name], the [CTO/Lead Developer] of [Your Company].

We currently have ["X" developers] working on our main Rails app.

The velocity of the team is not going up while adding developers because [code reviews takes too much time, QA is hard, CI is slow, Legacy code is huge, etc].

Also, I feel there are many AI tools out there and we are not sure which one to use. So we don't have a clear AI coding strategy for 2026.

Can you help us on this?

Current Stack: [examples]

Rails 6/7/8
Sidekiq/Good Job/Solid Queue
PostgreSQL/MySQL/MongoDB/...
Memcached/Redis (for BG jobs and caching)
Kubernetes on AWS/GCP/Azure/Bare Metal servers...
Bugsnag/Sentry/...
Github/Gitlab/Bitbucket/...

When are you able to jump in and help us?

See you soon

Or just book a call below directly 👇

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Your Business is Ready to Scale. Your Rails code base isn't.