Ruby on Rails Upgrades That Don't Break Your Business
Zero-downtime migrations from legacy Rails versions to modern, secure, high-performance applications. Trusted by startups, enterprises, and everything in between.
Is Your Rails Application Holding You Back?
Security Vulnerabilities Multiply
Unsupported Rails versions leave your application exposed to attacks that could compromise customer data, damage your reputation, and result in costly compliance violations.
Technical Debt Compounds Daily
Outdated gems become incompatible. New developers struggle with legacy patterns. Features that should take days stretch into weeks. Your velocity slows while competitors ship faster.
The Longer You Wait, The More It Costs
Each new Rails version introduces breaking changes. An upgrade from Rails 4.2 to 7.1 that might cost $50,000 today could balloon to $150,000 next year as dependencies drift further apart.
Can You Afford NOT To Upgrade?
The question isn't whether you can afford to upgrade—it's whether you can afford to keep running vulnerable, slow, increasingly unmaintainable code.
Rails Upgrades Done Right: Zero Downtime, Zero Surprises
As a dedicated Rails upgrade company, Allerin eliminates the fear and uncertainty from version migrations. Our rails version upgrade specialists have refined a battle-tested methodology through 50+ successful upgrades—from quick-win minor version bumps to complex multi-year legacy rescues.
What's Included
Complete Version Migration
Rails 3.x, 4.x, 5.x, 6.x to the latest stable Rails 7.x, including Ruby version upgrades
Dependency Audit & Updates
Every gem evaluated, updated, or replaced with maintained alternatives
Security Patching
All known CVEs addressed, authentication systems modernized, security best practices implemented
Performance Optimization
Database query optimization, caching improvements, and modern Rails performance features enabled
Test Suite Modernization
Existing tests updated, coverage gaps filled, CI/CD pipeline improvements
Zero-Downtime Deployment
Blue-green deployments, database migrations that don't lock tables, rollback strategies
Documentation & Knowledge Transfer
Your team understands every change we make. Complete documentation, code review sessions, and training included.
Rails Expertise for Every Stage of Business
Whether you're a startup preparing for scale or an enterprise managing mission-critical systems, our upgrade approach adapts to your unique requirements.
Startups & Scale-ups
You built fast to find product-market fit. Now that you've found it, technical debt from early decisions is slowing you down. We help startups upgrade efficiently without diverting your entire engineering team from feature development. Our approach focuses on speed, cost-efficiency, and setting you up for the next phase of growth.
Common scenarios: Preparing for Series A/B due diligence, scaling from MVP to production-grade, paying down technical debt before it compounds further.
Enterprise & Corporate
Large organizations can't afford downtime—period. Our enterprise engagements include comprehensive risk assessment, change management documentation, compliance verification, and coordination with your security and DevOps teams. We integrate seamlessly with your existing workflows, SDLC processes, and approval gates.
Common scenarios: SOC 2 / ISO 27001 compliance requirements, coordinating upgrades across multiple applications, augmenting internal teams during major migrations.
E-commerce & Retail
Every minute of downtime costs revenue. E-commerce upgrades require surgical precision—especially during peak traffic periods. We specialize in zero-downtime deployments that keep your checkout flowing, inventory syncing, and customers happy while we modernize your stack behind the scenes.
Common scenarios: Upgrading before Black Friday/holiday season, payment system modernization, performance optimization for traffic spikes.
SaaS & Multi-tenant
Multi-tenant architectures add complexity to any upgrade. Database migrations must preserve tenant isolation. API changes can't break customer integrations. We understand the nuances of SaaS Rails applications—from background job systems to webhook reliability to API versioning strategies.
Common scenarios: Upgrading multi-tenant databases, maintaining API backward compatibility, modernizing authentication (OAuth, SSO integration).
Government & Regulated Industries
Security isn't optional—it's mandated. We help government agencies and regulated industries (healthcare, finance, legal) upgrade Rails applications while maintaining strict compliance with FedRAMP, HIPAA, PCI-DSS, and other regulatory frameworks. Full audit trails, security documentation, and remediation reports included.
Common scenarios: Security vulnerability remediation under deadline, compliance audit preparation, air-gapped or restricted network deployments.
See how we've helped companies across industries modernize their Rails applications.
View our case studiesA Proven 6-Phase Upgrade Methodology
Our structured approach minimizes risk and keeps you informed at every stage. No black boxes, no surprises—just systematic progress toward a modern Rails application.
Discovery & Assessment
We conduct a comprehensive codebase audit covering Rails version, Ruby version, gem dependencies, test coverage, database structure, deployment infrastructure, and existing technical debt. You receive a detailed assessment report with risk analysis, recommended upgrade path, and effort estimate.
Deliverable: Upgrade Assessment Report with timeline, cost estimate, and risk analysis
Environment Setup & CI/CD Preparation
Before touching production, we establish a parallel upgrade environment. This includes staging infrastructure that mirrors production, CI/CD pipelines for the upgrade branch, rollback procedures, and monitoring dashboards.
Deliverable: Isolated upgrade environment with automated testing pipeline
Incremental Version Migration
Each rails version upgrade follows our proven methodology—we upgrade one minor version at a time, never skipping versions. This systematic approach surfaces issues incrementally. Each version bump includes gem compatibility updates, deprecation warning resolution, and full test suite validation.
Deliverable: Weekly progress reports with passing test suites at each version milestone
Security Hardening & Performance Optimization
With the version upgrade complete, we address all known CVEs, implement modern Rails security features (encrypted credentials, strong parameters audit, CSRF/XSS protection), and enable performance improvements available in the new Rails version.
Deliverable: Security audit report and performance benchmark comparison
Staging Validation & Load Testing
The upgraded application undergoes rigorous testing in a production-like environment. We conduct load testing, integration testing with external services, and coordinate user acceptance testing with your team.
Deliverable: QA sign-off, load test results, production deployment plan
Production Deployment & Support
Zero-downtime deployment using blue-green or rolling deployment strategies. Our team monitors in real-time, ready to execute rollback if needed. Includes 30 days of post-deployment support and knowledge transfer.
Deliverable: Production deployment, documentation package, 30-day support period
Upgrade Paths We Support
No matter how far behind your Rails version has fallen, we have a path forward. Our team has successfully completed upgrades across every major Rails version transition.
| From Version | To Version | Typical Timeline |
|---|---|---|
| Rails 3.x | Rails 7.x | 12-16 weeks (major refactoring required) |
| Rails 4.x | Rails 7.x | 8-12 weeks |
| Rails 5.x | Rails 7.x | 6-10 weeks |
| Rails 6.x | Rails 7.x | 4-6 weeks |
| Rails 7.0 | Rails 7.1+ | 2-4 weeks |
Ruby Version Upgrades: We also handle Ruby version upgrades (2.x to 3.x) as part of the migration, ensuring your entire stack is modern and supported.
Timelines are estimates based on typical applications. Actual duration depends on codebase size, test coverage, gem complexity, and team availability for reviews.
Why Companies Trust Allerin for Rails Upgrades
With 50+ successful migrations completed, Allerin is the Rails upgrade company enterprises trust for mission-critical applications.
Battle-Tested Methodology
Our 6-phase process has been refined through dozens of successful upgrades. We've encountered (and solved) the edge cases that break other approaches.
Zero-Downtime Expertise
We don't just upgrade your code—we deploy it safely. Blue-green deployments, database migrations that don't lock tables, and instant rollback capability.
Full Transparency
Weekly progress reports, access to our project management tools, and clear communication throughout. You're never left wondering about status.
Knowledge Transfer Included
We don't just hand you upgraded code—we ensure your team understands every change. Documentation, code review sessions, and training included.
Fixed-Price Options Available
After our assessment phase, we can offer fixed-price contracts for qualified projects. No surprise bills.
Post-Deployment Support
30 days of included support after go-live. If upgrade-related issues emerge, we fix them—period.
Frequently Asked Questions
Investment & Engagement Options
Every Rails application is different, and cookie-cutter pricing doesn't work for upgrades. That said, we believe in transparency. Here's how we structure engagements:
Assessment Phase
Comprehensive codebase audit with detailed upgrade roadmap, risk analysis, and effort estimates.
Credited toward full project if you proceed
Standard Upgrades
- Minor version upgrades (1-2 versions): $10,000 - $35,000
- Major version upgrades (Rails 5/6 → 7): $35,000 - $75,000
Legacy Rescue
For Rails 3.x/4.x applications requiring significant refactoring, gem replacements, and extensive testing.
Engagement Models
Fixed Price
Available after assessment for well-defined scopes. Best for straightforward upgrades with good test coverage.
Time & Materials
Flexible engagement with weekly billing. Best for complex legacy applications or when scope may evolve.
Dedicated Team
Full-time engineers embedded with your team. Best for large enterprises with multiple applications.
Ready to Modernize Your Rails Application?
Start with a free assessment. We'll analyze your codebase, identify risks and blockers, and provide a detailed roadmap—with no obligation to proceed. Most assessments are completed within 5 business days.
At a Glance
Compatibility Matrix
Protocols
Message Brokers
Message Formats
Target Systems
Real Impact: Measured Before & After
Industry Deployment Patterns
How different industries upgrade Rails applications without feature freeze and with proven performance gains.
Finance & Fintech
SaaS Platform Upgrade (Rails 6.1 → 7.1)
Upgraded fintech API serving 2.4M transactions/day. Zero downtime, p95 from 1.8s → 680ms. PCI-DSS compliance maintained throughout. 18 CVEs eliminated.
Retail & E-Commerce
E-commerce Monolith Upgrade (Rails 5.2 → 7.1)
Black Friday-ready Rails upgrade for 800K SKU catalog. 55% memory reduction enabled downsizing from 24 to 14 dynos. $86k annual savings.
Healthcare & MedTech
HIPAA-Compliant Patient Portal (Rails 4.2 → 7.1)
Multi-version Rails upgrade with audit trail preservation. BAA compliance maintained. Zero data loss during dual-boot migration.
Architecture Decision Guide
Choosing the right Rails upgrade strategy for your team size, risk tolerance, and deployment constraints.
| Approach | When to Use | Tradeoffs | Best For |
|---|---|---|---|
| Dual-Boot | Monolith with active feature work | Longer timeline (6-8 weeks), more CI complexity, but zero feature freeze | Teams shipping 20+ PRs/week, high-traffic apps, SaaS platforms |
| Blue-Green | Clean cutover, strict rollback SLA (<10 min) | Requires 2x infrastructure temporarily, simpler CI setup | High-availability systems, financial services, enterprise SaaS |
| In-Place + Canary | Small teams, lower traffic, faster timeline | Higher risk, requires robust monitoring and alerting | Startups, MVPs, low-complexity apps (<50K LOC) |
Outcomes
See the math →- •Same-day cutovers with dual-boot and safe migrations (no freeze)
- •Zero critical CVEs at release; dependency policy enforced in CI
- •p95 down ≥ 30% on named hot paths; error rate not worse
- •Deploy frequency ≥ daily with automatic canary and rollback
- •Infra and DB cost reduced 20-40% with YJIT, caching, pool tuning
What You Get (Acceptance Criteria)
Our standards →Upgrade plan: Ruby X→Y, Rails A→B; gem audit and shim strategy
Dual-boot enabled; green path proven in staging with traffic replay
Zero-downtime migrations via strong_migrations / gh-ost / pt-osc; backout path
CI/CD hardening: matrix builds (old/new), contract tests, flaky-test quarantine
Observability pack: pre/post p95, p99, error budgets, Slow Query log reports
Performance fixes: N+1 elimination; index strategy, partitioning; cache keys
Security hardening: Brakeman, bundler-audit/Snyk, CSP/HSTS, CSRF, session store, key rotation
Cost controls: puma worker math, pgbouncer, env-specific pool sizes, object store offload
Cutover runbook: canary %, health gates, 'abort switch,' rollback <10 min
Post-go-live hypercare (2-4 weeks) with SLO watch
Timeline
4-8 weeks
Team
Rails lead, BE, SRE/DevOps, QA, Sec reviewer
Inputs We Need
- •Codebase + Gemfile.lock, production configs, deploy scripts
- •Current perf/security reports; SLOs; infra costs; DB stats (pg_stat_statements)
- •Release calendar and downtime constraints
- •List of critical user journeys and SLAs
- •Access to CI/CD, observability, error tracking, DB consoles
Tech & Deployment
⚡Target Stack at a Glance
Runtime & Server
Ruby 3.2/3.3 with YJIT/IRB 1.10; Bundler 2; Rails 7.x (Zeitwerk) · Puma 6; Rack 3 readiness; Bootsnap; async query where safe
Database & Migrations
PostgreSQL ≥13 (JIT, parallel query), pgbouncer, statement_timeout, query plan reviews, partitioning where needed · strong_migrations, concurrent indexes, backfill jobs, feature-flagged reads
Background Jobs & Assets
Sidekiq/Resque/GoodJob with idempotency keys; unique jobs; retry jitter · CSS bundlers (Propshaft/Vite), JS bundler (esbuild/Vite), Turbo/Stimulus as needed
Deployment & Observability
Kubernetes/Heroku/EC2; blue/green, canary with traffic weights; secrets in KMS; read-only step if needed · OpenTelemetry, Datadog/New Relic/Grafana; Sentry/Honeybadger for errors
Timeline: Week 1-2: audit, plan, dual-boot scaffold, CI matrix, env parity · Week 3-5: gem upgrades, migrations, perf/security fixes, test stabilization · Week 6-8: canary + blue/green, cutover rehearsal, hypercare
Tech & Deployment
Ruby 3.2/3.3 with YJIT; Rails 7.x (Zeitwerk); Puma 6; PostgreSQL ≥13; strong_migrations; pgbouncer; OpenTelemetry; Datadog/New Relic/Grafana
Proof We Show
Full evidence list →Frequently Asked Questions
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Learn more →Product Pods
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Learn more →Ready to Get Started?
Book a free 30-minute scoping call with a solution architect.
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