--- title: Quarkus Insights #256: What is Floci? | daily.dev description: Floci is a free, open-source multi-cloud emulator suite built on Quarkus native image, created by Hector Ventura. Unlike mocking or simulation tools, Floci... canonical: https://daily.dev/posts/quarkus-insights-256-what-is-floci--sajk9qne5 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Quarkus Insights #256: What is Floci? | daily.dev og:description: Floci is a free, open-source multi-cloud emulator suite built on Quarkus native image, created by Hector Ventura. Unlike mocking or simulation tools, Floci... og:url: https://daily.dev/posts/quarkus-insights-256-what-is-floci--sajk9qne5 og:image: https://api.daily.dev/og/posts/SAJK9Qne5.png og:image:alt: Quarkus Insights #256: What is Floci? og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Quarkus Insights #256: What is Floci? **[Quarkus](https://daily.dev/sources/quarkus)** · 8 min read · 1 upvotes · 0 comments ## Summary Floci is a free, open-source multi-cloud emulator suite built on Quarkus native image, created by Hector Ventura. Unlike mocking or simulation tools, Floci provides true emulation — storing and returning real data — for AWS, Azure, GCP, and Oracle OCI, each running in its own container. Compiled to a GraalVM native image via Quarkus, it achieves 24 ms startup time and 13 MB idle memory. It integrates with Quarkus Dev Services as a drop-in replacement for LocalStack (which archived its community edition shortly after Floci launched). Floci offers four storage modes (memory, persisted, hybrid, write-ahead log) and is increasingly used for AI agent sandboxing, where isolated, disposable cloud environments per agent eliminate risks of LLM operations touching real cloud accounts. Upcoming features include CloudFormation expansion and 'Floci Pods' — portable snapshots of complete environment state for reproducible bug reports. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is Floci and how does it differ from LocalStack? Floci is a free, open-source suite of local cloud emulators built on Quarkus native image, covering AWS, Azure, Google Cloud Platform, and Oracle OCI. It launched as open source on March 15, a week before LocalStack archived its community edition, and unlike mocking or simulation tools, it emulates real state: stored objects are actually returned when requested. It runs as a native image with 24ms startup time and 13MB idle memory. _Teams evaluating a LocalStack replacement can follow Floci's progress and releases on daily.dev._ ### How do I switch Quarkus Dev Services from LocalStack to Floci? Switching is purely a configuration change since Quarkus Dev Services uses the same Testcontainers mechanism that talks to the Docker socket, now supporting multiple providers including Floci. No application code changes are needed because the code still talks to the original AWS, Azure, or GCP SDK, just pointed at a different local endpoint. _Developers migrating their Quarkus Dev Services setup can track configuration changes like this on daily.dev._ ### What storage modes does Floci support for local cloud emulation testing? Floci offers four storage modes: Memory (fastest, data lost on stop, good for AI agent sandboxing), Persisted (every write goes to disk immediately, deterministic for test fixtures), Hybrid (writes go to memory and flush to disk asynchronously, inspired by PostgreSQL's write-ahead log), and Write-ahead-logging (tailored for write-heavy workloads). _Engineers designing reproducible test fixtures with local emulators can find setup details like these on daily.dev._ ## Similar posts on daily.dev - [Foojay Podcast \#96: Local AWS Development Without LocalStack: Meet Floci, the GraalVM-Powered Alternative](https://daily.dev/posts/foojay-podcast-96-local-aws-development-without-localstack-meet-floci-the-graalvm-powered-altern-e7k84zsvt) · Foojay.io · 3 upvotes · 0 comments - [GitHub - hectorvent/floci: Light, fluffy, and always free - AWS Local Emulator](https://daily.dev/posts/github---hectorvent-floci-light-fluffy-and-always-free---aws-local-emulator-hbh0ekama) · Hacker News · 65 upvotes · 2 comments - [foojay – a place for friends of OpenJDK](https://daily.dev/posts/foojay-a-place-for-friends-of-openjdk-dbnwbeufs) · Foojay.io · 5 upvotes · 0 comments - [Hashtag Jakarta EE \#342](https://daily.dev/posts/hashtag-jakarta-ee-342-yujdjtttt) · Jakarta EE · 2 upvotes · 0 comments --- Tags: [#java](https://daily.dev/tags/java), [#quarkus](https://daily.dev/tags/quarkus) [View this post on daily.dev](https://daily.dev/posts/quarkus-insights-256-what-is-floci--sajk9qne5) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Quarkus Insights #256: What is Floci?","url":"https://daily.dev/posts/quarkus-insights-256-what-is-floci--sajk9qne5","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/quarkus-insights-256-what-is-floci--sajk9qne5"},"datePublished":"2026-08-11T20:36:03.927Z","dateModified":"2026-09-14T06:53:50.129Z","description":"Floci is a free, open-source multi-cloud emulator suite built on Quarkus native image, created by Hector Ventura. 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