ERP Migration for SMEs: From Audit to Switchover, with Zero Downtime
Technologies & Partenaires
Who will build your project
No anonymous outsourcing: meet the people who will design, build and ship your solution.
Victor Gless-Krumhorn
Founder & Lead Developer
Prépa HEC, Paris-Dauphine (Finance & Wealth Management). Former UBS. Reserve NCO in the French Army. Full-Stack Developer specializing in Ruby on Rails — leads JAIKIN's technical strategy and product direction.
Patrick Eiermann
Senior Full-Stack Developer
Epitech graduate with 8+ years of software engineering experience, specialized in Node.js and DevOps. Designed an airline ERP system, e-commerce platforms, and production SaaS applications. Owns back-end architecture and systems integration.
1 in 2
ERP migrations that overrun (budget or schedule)
6-18 months
typical average duration
2 h
tested rollback (revert plan)
+130
projects delivered (team total)
Why migrate your ERP in 2026 -- and why custom is becoming accessible again
Your ERP is 5, 10, 15 years old. It has become a patchwork of customizations, parallel Excel spreadsheets and workarounds. Every update is a headache. Every new business need requires months of adaptation. Maintenance costs are skyrocketing, but the cost of migration is daunting.
To prepare for the future, a custom CRM/ERP is becoming a solid option again. Why? Because the cost of code tends to drop with AI (AI-assisted development noticeably reduces implementation time depending on the task), making custom development finally affordable for SMEs. The competitive advantage of owning your ERP and configuring it exactly to your needs is at its peak today.
At JAIKIN, we support SMEs through their ERP migration -- whether to a SaaS solution (Odoo, ERPNext, NetSuite) or to a custom development. Our proven method guarantees business continuity, data preservation and a painless deployment.
The right time to migrate
The first thing to do is to have your current ERP audited. Even if you don't launch the migration immediately, the audit gives you a clear picture of your technical debt, the hidden costs of your current system, and a costed roadmap. It's the most useful preparatory investment you can make.
Why ERP migrations fail
The mistakes are almost always the same. Avoiding them is our specialty.
Data loss or corruption
Database migration is failure point #1. Years of history, customer relationships, transactions -- everything can be lost if the data migration is botched.
Business interruption
Every hour of downtime costs money. A poorly planned migration can paralyze the business for days -- invoicing blocked, orders lost, unhappy customers.
Vendor lock-in
Migrating from one proprietary ERP to another proprietary ERP is just changing prisons. The winning long-term strategy: keep control over your data and code.
Cost explosion
The initial quote never covers everything. Unplanned customizations, forgotten integrations, insufficient training -- hidden costs pile up.
Timeline drift
6 months become 12, then 18. Every unexpected issue pushes back the go-live date and demoralizes teams.
User rejection
Even an excellent ERP is useless if teams don't use it. Resistance to change is the silent killer of migration projects.
Our migration method: a proven 7-phase approach
Each phase is designed to minimize risk and guarantee business continuity. No big bang -- a gradual, controlled transition.
Audit and mapping of existing systems
1-2 weeksComplete mapping of your current ERP: modules used, customizations, data flows, integrations, volumes. Identification of technical debt and quick wins.
-> The foundation for realistic costing
Data preparation and cleanup
2-4 weeksData quality audit. Cleanup, deduplication, enrichment. This is how we ensure that migrated data is clean and usable.
-> Most migration failures come from poorly prepared data
Test environment and parallel run
2-4 weeksThe new system runs in parallel with the old one for 2-4 weeks. Teams test, compare results, and report discrepancies. Zero risk to production.
-> The guarantee that everything works before switchover
A/B testing and business validation
1-2 weeksThe method to validate a migration: run the same business scenarios on the old and new systems in parallel and compare results. Invoicing, orders, inventory, payroll -- every critical process is tested.
-> Every discrepancy is documented and fixed before switchover
Weekend switchover with rollback plan
1 weekendGood practice for the switchover: intervention on the weekend when activity is at its lowest. Final data migration, full verification, non-regression testing. If a critical issue is detected, the rollback plan allows reverting in 2 hours.
-> Monday morning, teams are working on the new system
Enhanced post-migration support
2 weeksDuring the first 2 weeks after switchover, our team is available continuously to resolve issues, adjust settings and train users on real-world cases.
-> Response time < 30 minutes on critical incidents
Continuous optimization
OngoingA good ERP is one that evolves with your business. After stabilization, we continue to optimize: new modules, additional automations, custom reports.
-> Your ERP improves every month
Custom ERP vs SaaS vs Legacy: which choice for your SME?
| Criteria | Custom ERP (recommended) | SaaS ERP (Odoo, NetSuite) | Legacy ERP (SAP, Sage X3) |
|---|---|---|---|
| Initial cost | Medium -- declining thanks to AI | Low to medium | Very high |
| 5-year cost (TCO) | Lowest -- no recurring license | High (licenses x users x years) | Very high (licenses + maintenance) |
| Flexibility | Total -- tailored to your business | Limited by available modules | Very limited, costly customization |
| Scalability | Unlimited -- you own the code | Depends on the vendor | Often blocked by version constraints |
| Data ownership | 100% ownership | Data held by the vendor | Proprietary formats, difficult export |
| Evolution speed | Immediate -- your priorities, your pace | Depends on the vendor roadmap | Slow -- depends on major releases |
Database migration: audit, mapping, validation -- zero loss
Database migration is the technical heart of the project. Years of customer data, transactions, order histories -- everything must be transferred without loss, corruption, or duplicates. Our approach combines a data quality audit (completeness, consistency, uniqueness), automated schema transformation, and exhaustive post-migration validation.
Data audit
Quality analysis, completeness, duplicates, orphans. Detailed report with cleanup recommendations.
Transformation & mapping
Schema conversion, field mapping, tested and versioned migration scripts. Every transformation is reversible.
Exhaustive validation
Record counting, checksums, referential integrity tests. Signed validation report before go-live.
Business continuity: our zero-downtime commitment
Hot migration
Data is synchronized in real time between the old and new systems during the transition phase. No data lost, no double entry.
Tested rollback plan
Your insurance against the unexpected. If a critical issue is detected during switchover, we revert to the old system in under 2 hours. The rollback plan is tested before every migration.
Weekend switchover
The intervention takes place on the weekend to minimize impact on your operations. Monday morning, your teams start on the new system with enhanced support.
ERPs and CRMs we migrate
From old to new, regardless of the combination.
They trust us
Projects delivered by our team — JAIKIN × Azinove Group
« Our WhatsApp requests become structured purchase orders in seconds, on a custom staffing platform. »
DT INTERIM
HR — temporary staffing
« Victor from JAIKIN took over our old website content, enriched it with relevant material without taking up my time — and we are climbing the rankings. Inquiries keep coming in. »
David K.
Managing Director, Kappeler — illuminated signage (since 1962)
« JAIKIN has been our technology delivery partner from the very first execution phase. »
Tomislav Lang
CEO & Co-founder, Flyvbird — aviation
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Frequently Asked Questions About ERP Migration
The safest method is the progressive 7-phase migration with parallel run and weekend switchover. It takes longer than a big bang, but it's the only approach that guarantees business continuity and allows you to fix issues before they impact production.
The cost varies depending on complexity: from 15,000 EUR for a simple migration (SME with 10-20 users, standard ERP) to 80-150,000 EUR for a complex migration with custom development. The recommended approach is to start with an audit (2-3 days, a few thousand euros) to get a realistic estimate.
The answer depends on your business. If your processes are standard (accounting, sales, inventory), a SaaS like Odoo is sufficient. If you have specific business processes that drive your competitive advantage, custom development is the way to go -- and its cost has dropped thanks to AI.
Through a 3-step process: audit of the existing database (counting, quality control), migration with checksums, then exhaustive post-migration validation (counting, referential integrity, business tests). Each step produces a signed report.
It's the recommended practice to minimize impact on your operations. The final switchover (shutting down the old system, syncing the last data, activating the new one) takes 4-8 hours. By doing it on Saturday, your teams find a fully operational system on Monday morning.
That's why we test the rollback plan before every migration. If a critical issue is detected during switchover, we revert to the old system in under 2 hours. All data entered during the migration attempt is recovered.
With our method: 6-12 weeks for a standard SME, 3-6 months for a complex migration. That's 2-3x faster than traditional approaches thanks to AI, which accelerates data mapping, connector development and testing.
Yes, but in a targeted way. Key users (1-2 people per department) are involved during testing and validation phases, about 2-3 hours per week. We recommend identifying these key users early and involving them from the audit stage.
Absolutely. It's actually one of our most common cases. Many SMEs have built their 'ERP' on Access, Excel or internal tools. The approach is to map all these scattered flows and consolidate them into a single system -- custom or SaaS.
It's the reference validation method. You run the same business scenarios (create an order, generate an invoice, calculate inventory) on the old and new systems in parallel. If the results are identical, you validate. If a discrepancy is detected, you fix it before the switchover. It's the guarantee that the new system produces the same results as the old one.
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