The Challenge
A global retailer operating thousands of Spring-based services across its e-commerce, checkout, inventory, and supply chain platforms faced a mounting modernization risk. Over time, teams had adopted a wide range of Spring Boot versions—spanning from legacy 1.3 releases to early 3.x deployments—creating fragmentation that slowed upgrades and increased operational risk.
Security vulnerabilities and framework updates could not be handled in isolation. With peak retail periods approaching, the organization needed a way to modernize thousands of repositories quickly and safely—without pulling engineers away from critical customer-facing work or relying on brittle, manual migration efforts.
The scale of the environment made traditional approaches impractical. Coordinating upgrades repo by repo would have required weeks of effort per team and introduced unacceptable risk during high-traffic retail windows. The platform engineering organization needed a solution that could deliver consistency, speed, and confidence across hundreds of teams at once.
3,500+
Repos migrated to Spring Boot 3.x
4,000+
Repos aligned on Java 17
Thousands
Repos modernized across global retail platform
The Solution
Moderne enabled Spring Boot migrations to run as coordinated campaigns—without central bottlenecks or manual intervention.
To address the challenge, the retailer partnered with Moderne to automate and orchestrate Spring Boot migrations at enterprise scale. Rather than centralizing changes through a single team, Moderne enabled developers to execute upgrades within their existing workflows—while ensuring consistency and safety across the entire codebase.
Using automated refactoring recipes, the platform engineering team coordinated Spring Boot 3 migrations across thousands of repositories in parallel. Moderne also supported custom modernization patterns for internal libraries, allowing teams to apply organization-specific standards without manual intervention.
By combining automation with developer-owned execution, the retailer established a repeatable modernization process—one that could handle both urgent security updates and long-term framework evolution without disrupting day-to-day development.
At our scale, even small inconsistencies can ripple across the entire customer experience. Moderne ensures we never fall behind again so we can operate with confidence during peak periods.
Results
What once required weeks of coordination and manual effort became a repeatable, automated process executed in parallel across the organization.
With Moderne, the retailer successfully modernized its Spring ecosystem ahead of critical retail periods, significantly reducing risk while accelerating delivery. Thousands of repositories were upgraded in parallel, enabling teams to move to Spring Boot 3.x and Java 17 without weeks of manual coordination.
The organization not only completed a major framework transition, but also established a scalable foundation for future upgrades—including preparation for upcoming Spring Boot 4 releases. What had once been a high-risk, time-consuming effort became a repeatable, automated process embedded into the company’s development lifecycle.
Beyond the Upgrade: Enterprise-Scale Impact
Portfolio-wide visibility
Moderne gave the platform engineering team real-time visibility into Spring Boot versions, dependency drift, and migration readiness across thousands of repositories—making risk measurable instead of anecdotal.
Migration logic encoded once
Spring Boot upgrade knowledge was captured as reusable OpenRewrite recipes, ensuring every repository followed the same rules, standards, and safety checks—without relying on tribal knowledge or manual reviews.
Parallel execution without coordination overhead
Teams could run migrations across hundreds or thousands of repositories simultaneously, without creating merge conflicts, blocking releases, or pulling engineers away from customer-facing work.
Future upgrades become routine
With Spring Boot 3.x and Java 17 complete, the organization established a repeatable process for future framework evolution—reducing the cost, risk, and effort of upcoming Spring Boot releases.
Dive Deeper
Spring Boot upgrades at scale
Moderne enables deterministic, repeatable Spring Boot modernization across entire code estates, with testable changes powered by Lossless Semantic Trees for accuracy at enterprise scale.
Spring Boot 4x migration guide
Spring Boot 4.0 represents the new foundation the Spring ecosystem will build on for years. The sooner teams standardize on this baseline, the sooner they unlock the performance, security, and developer-experience improvements.
Migrate frameworks
automatically before EOL
Maintaining an up-to-date tech stack has many benefits for your organization, including more secure code, faster delivery, better app performance, and lower support costs.
