Recovery, proven: a full failover test in 49 minutes
Auditors don't ask whether you have backups, they ask whether they work. Three restore tests in a single day: a database restore in 90 seconds, point-in-time recovery to the second, and a full failover test in 49 minutes. Measured, not estimated.
Your KVM hosts allow nested virtualization. You never decided that.
Januscape (CVE-2026-53359): root in a guest, a nested guest, a corrupted host kernel. The preconditions: a kernel default plus the CPU type you pick for performance. The path was open on every host, for nothing. How we closed it as permanent policy.
Your demo image is arm64, your cluster is amd64
An arm64 Mac builds an image your amd64 cluster can't run: exec format error on stage. How to build cross-platform Quarkus images with Jib, no QEMU, no buildx, no daemon.
Testcontainers reuse: 172 zombie containers ate my laptop
Reusable containers are excluded from Ryuk by design. With reuse enabled, every branch switch leaks a fresh postgres container. How I found 172 of them, and the two-line fix.
Sovereign cloud: an honest answer to a word nobody can define
Nobody can define "sovereign cloud", not even the Dutch government. So we don't go along with the hype. The honest version: who can legally reach your data, where it physically lives, and how you leave.
Docker 29 breaks Testcontainers: "client version 1.32 is too old"
Docker 29 raised its minimum API version to 1.40. The docker-java client Testcontainers ships negotiates down to 1.32, so self-hosted CI hits a 400 the moment it pulls a fresh dind. Here's why, and the one-line fix.
Quarkus on JDK 25: when the AOT cache assumes a CPU your hardware doesn't have
SIGILL in AdapterBlob, hs_err analysis, and what JEP 483 doesn't tell you about portability. Plus where the same trap waits on Proxmox, VMware EVC, AMD EPYC Rome/Milan, and the RHEL 10 v3 baseline.
JAVA_OPTS_APPEND on Red Hat UBI Java images is a fallback, not an append
Setting JAVA_OPTS silently discards JAVA_OPTS_APPEND. The name is misleading. Here's how it actually behaves on ubi9/openjdk-25, why, and how to detect it in 30 seconds.
Kubernetes without cluster management: which approach fits your team?
You want the benefits of Kubernetes without managing a cluster yourself. From managed containers to a fully managed platform: which approach fits your team?
Year in Review 2025: Three Datacenters and Ready for Growth
From one to three datacenter locations in 2025. A look back at DC2, DC3, Kubernetes for clients, and the infrastructure that makes it possible.
Java 25 arrives: what CoffeeSprout customers need to know
Java 25 is now generally available, closing out another six-month release cycle. Learn what changed, when CoffeeSprout rolls it out, and how to request early access.
New location: CoffeeSprout expands to underground bunker for extra reliability
CoffeeSprout announced a second hosting location deep underground in a former Cold War bunker near Hazerswoude-Dorp. The facility offers stable temperature, physical security, and protection from above-ground risks.
Off-site backups: soon stored even colder in Scaleway Glacier
We're adding Scaleway Glacier to our backup infrastructure for long-term cold storage. This complements our existing twice-daily backups and monthly tape archives.
Transactional email options at CoffeeSprout
When your application needs to send emails reliably, you need a proper transactional email setup. We explain the options: self-hosted solutions, managed SMTP relays, and API-based services.
Our refreshed website
We refreshed our website to better explain what CoffeeSprout does and how we help teams run Java applications reliably. The new design focuses on clarity and transparency.