Nextory

Nextory transforms its media processing pipeline with agentic AI and Google Cloud

Results on Google Cloud
  • Migrated 100,000 lines of Ruby code in eight weeks

  • Reduces publisher onboarding from months to a week

  • Cuts large-book processing from 80 minutes to two

  • Builds repeatable agentic AI migration practices

Nextory worked with Google Cloud to map, analyze, and modernize its media processing system in just eight weeks using agentic AI.

smartphone screen displaying a curated grid of video thumbnails

Choosing a faster path to legacy modernization

Nextory is one of Europe’s largest sources for audiobooks, ebooks, and digital magazines. Working with hundreds of publishers across the world, the streaming platform aims to provide readers with everything from the latest releases to the classics. Each new publishing agreement means back catalogs of hundreds of thousands of titles to process at once—something Nextory’s legacy Ruby on Rails architecture was increasingly struggling to keep up with.

The team recognized that the system needed to be rebuilt, but the scale of the effort raised concerns: The project was estimated at up to two developer years, while Ruby expertise was becoming increasingly hard to source. In search of a faster, lower-risk path, Nextory turned to Google Cloud. “We had started looking at Google tools like Google Antigravity and Gemini CLI, and saw a chance not only to rebuild our ingestion system, but also learn a repeatable way to use agentic AI on legacy code,” explains Mattias Engblom, CTO at Nextory.

We had started looking at Google tools like Antigravity and Gemini CLI, and saw a chance not only to rebuild our media processing system, but also learn a repeatable way to use agentic AI on legacy code.

Mattias Engblom

CTO, Nextory

Working with Google Cloud engineers, the team built a structured agentic workflow, first mapping the legacy system, then testing new architecture options before committing to the rebuild. In just eight weeks, Nextory migrated 100,000 lines of Ruby code, a project estimated at around six or seven months.

From legacy code to a migration blueprint

The migration took place in two phases. First, Nextory and Google Cloud teams worked together to reverse-engineer the existing codebase using Antigravity and Gemini CLI. The teams began by creating specialized agent skills to audit the Ruby codebase and map the logic behind the existing ingestion process. The tools helped extract functional and architectural behavior, map workflows, identify edge cases, and generate structured artifacts, including technical design documents, critical user journeys, and test cases that could be used as a baseline for the new system.

The Google Cloud team showed us the importance of using agentic skills to reverse-engineer the process. Using Antigravity and Gemini CLI, we were able to do in two to four weeks what would have taken six or seven months manually.

Sathish Yellanty

Sr. Staff Engineer, Nextory

“The Google Cloud team showed us the importance of using agentic skills to reverse-engineer the process,” says Sathish Yellanty, sr. staff engineer at Nextory, “Using Antigravity and Gemini CLI, we were able to do in two to four weeks what would have taken six or seven months manually.”

This preparation reduced discovery work and helped the team move beyond a line-by-line rewrite. With documentation and tests in place before new code was generated, engineers could compare each new implementation against the original system’s expected behavior.

The second phase was the four-day co-engineering week, an intensive in-person engineering sprint in which Google Cloud and Nextory engineers worked side by side. The teams used agents to build and compare Java, Python, and Go prototypes of the same business logic, and compared deployment options, including Cloud Run and Google Kubernetes Engine (GKE).

By the third day, the team had settled on a new architecture: Python for faster audio processing, Java for the ingestion model, Pub/Sub to decouple each stage of the workflow, Workflows to coordinate the process, and Cloud Run to scale processing capacity automatically. The result was not just a faster implementation, but an event-driven architecture that removed hard-coded dependencies, improved scalability, and gave Nextory a clearer model for future extendability.

A new operating model for technical debt

Instead of pushing a large audiobook through a largely sequential pipeline, the new architecture splits work into parallel tasks, with the team no longer needing to manage nodes or provision infrastructure for peaks. The combination of agentic workflows and the Nextory team knowledge of the existing system helped identify what business logic should be kept as part of the new code and what orchestration logic can be pushed down to Google Cloud.

One benchmark example was the Chinese translation of “War and Peace,” which is around 250 chapters long. Nextory can now spin up 250 processing instances and run each chapter in parallel, so overall processing time is determined by the longest chapter rather than the full book. Large-file media processing now takes around two minutes rather than 80, meaning that publisher onboarding, previously measured in months, now takes about a week.

For Nextory, the migration showed that technical debt doesn’t always need to be addressed through long manual rebuilds. With the right specifications, test coverage, and human review, agentic tools can turn modernization into a repeatable engineering practice.

We talk a lot about how much faster the process was compared to a traditional migration. But the important thing is that we gained that speed while maintaining quality—even improving it. It’s easy to do things fast, but we also built a system that works really well.

Mattias Engblom

CTO, Nextory

“This project visualized the way we should work going forward. The migration itself was valuable, but learning to work with agentic AI and seeing how much more efficient we can be was huge,” says Engblom. “The Google Cloud team never just said, ‘Do this.’ They guided us through different options, helped us understand the skills, and showed us how to use them efficiently in our day-to-day work.” The company is now exploring the ways it can operationalize agentic development: what context agents need, at what stage, and for which product teams.

“We talk a lot about how much faster the process was compared to a traditional migration,” Engblom concludes. “But the important thing is that we gained that speed while maintaining quality—even improving it. It’s easy to do things fast, but we also built a system that works really well.”

Nextory is one of Europe’s largest streaming services for audiobooks, ebooks, and digital magazines, working with hundreds of publishers across 10 European markets.

Industry: Media and Entertainment

Location: Sweden

Products: Google Cloud, Cloud Run, Gemini CLI, Google Antigravity, Google Kubernetes Engine, Pub/Sub, Workflows

  • Produits Google Cloud
  • Parcourez plus de 100 produits. Les nouveaux clients bénéficient de 300 $ de crédits gratuits pour exécuter, tester et déployer des charges de travail. Tous les clients peuvent utiliser plus de 25 produits gratuitement, dans les limites mensuelles spécifiées.
Google Cloud