Alexander Reelsen
@spinscale.bsky.social
Husband, dad, enjoys working distributed, likes distributed databases & search engines, the JVM, Basketball/Streetball fan, gulps coffee, lives in Emsdetten/Germany, occasionally blogs at https://spinscale.de
Have your Iceberg Cubed, Not Sorted: Meet Qbeast, the OTree Spatial Index
TIL about OTree, a novel multidimensional index with efficient data sampling, suitable for distributed data stores apparently. The article also links to the corresponding paper.
TIL about OTree, a novel multidimensional index with efficient data sampling, suitable for distributed data stores apparently. The article also links to the corresponding paper.
Have your Iceberg Cubed, Not Sorted: Meet Qbeast, the OTree Spatial Index — Jack Vanlightly
In today’s post I want to walk through a fascinating indexing technique for data lakehouses which flips the role of the index in open table formats like Apache Iceberg and Delta Lake. We are going…
jack-vanlightly.com
November 30, 2025 at 1:56 PM
Have your Iceberg Cubed, Not Sorted: Meet Qbeast, the OTree Spatial Index
TIL about OTree, a novel multidimensional index with efficient data sampling, suitable for distributed data stores apparently. The article also links to the corresponding paper.
TIL about OTree, a novel multidimensional index with efficient data sampling, suitable for distributed data stores apparently. The article also links to the corresponding paper.
polianna - a Java library/agent allowing to push JVM metrics via OTEL
Also allows for native memory tracking, heap allocation rate, direct buffers and others.
Also allows for native memory tracking, heap allocation rate, direct buffers and others.
GitHub - apple/pollianna
Contribute to apple/pollianna development by creating an account on GitHub.
github.com
November 29, 2025 at 1:56 PM
polianna - a Java library/agent allowing to push JVM metrics via OTEL
Also allows for native memory tracking, heap allocation rate, direct buffers and others.
Also allows for native memory tracking, heap allocation rate, direct buffers and others.
kimojo-rs: A thread-per-core Linux io_uring async runtime for Rust optimized for latency
Coming from azure, so I assume it's used in some modern data store, but apparently I missed the announcement.
Coming from azure, so I assume it's used in some modern data store, but apparently I missed the announcement.
GitHub - Azure/kimojio-rs: A thread-per-core Linux io_uring async runtime for Rust optimized for latency.
A thread-per-core Linux io_uring async runtime for Rust optimized for latency. - Azure/kimojio-rs
github.com
November 28, 2025 at 1:56 PM
kimojo-rs: A thread-per-core Linux io_uring async runtime for Rust optimized for latency
Coming from azure, so I assume it's used in some modern data store, but apparently I missed the announcement.
Coming from azure, so I assume it's used in some modern data store, but apparently I missed the announcement.
Why On-Prem Kubernetes is Hard
Nice article about the complexities and additional workload of running kubernetes yourself instead of using a cloud k8s service. First time I heard about "Day-2 operations", but I guess I am just hopelessly out of date once again.
Nice article about the complexities and additional workload of running kubernetes yourself instead of using a cloud k8s service. First time I heard about "Day-2 operations", but I guess I am just hopelessly out of date once again.
Building the Cloud Native Data Center – Part 2: Why On-Prem Kubernetes is Hard
Running Kubernetes on-prem is far harder than running it in the cloud. Let’s find out why.
meltcloud.io
November 27, 2025 at 1:56 PM
Why On-Prem Kubernetes is Hard
Nice article about the complexities and additional workload of running kubernetes yourself instead of using a cloud k8s service. First time I heard about "Day-2 operations", but I guess I am just hopelessly out of date once again.
Nice article about the complexities and additional workload of running kubernetes yourself instead of using a cloud k8s service. First time I heard about "Day-2 operations", but I guess I am just hopelessly out of date once again.
Building a Durable Execution Engine With SQLite
Great article with accompanying Java code, that uses annotations, bytebuddy and sqlite to be able to resume jobs. Great to follow explanations plus code.
Great article with accompanying Java code, that uses annotations, bytebuddy and sqlite to be able to resume jobs. Great to follow explanations plus code.
Building a Durable Execution Engine With SQLite
Lately, there has been a lot of excitement around Durable Execution (DE) engines. The basic idea of DE is to take (potentially long-running) multi-step workflows, such as processing a purchase order…
www.morling.dev
November 26, 2025 at 1:56 PM
Building a Durable Execution Engine With SQLite
Great article with accompanying Java code, that uses annotations, bytebuddy and sqlite to be able to resume jobs. Great to follow explanations plus code.
Great article with accompanying Java code, that uses annotations, bytebuddy and sqlite to be able to resume jobs. Great to follow explanations plus code.
Using ADBC in Java
JNI bindings for for the C++ ADBC driver. Not yet fully feature complete though.
JNI bindings for for the C++ ADBC driver. Not yet fully feature complete though.
Using ADBC in Java
New JNI bindings bring ADBC drivers to Java applications
columnar.tech
November 25, 2025 at 1:56 PM
Using ADBC in Java
JNI bindings for for the C++ ADBC driver. Not yet fully feature complete though.
JNI bindings for for the C++ ADBC driver. Not yet fully feature complete though.
Two KubeCons, One Conference: While Everyone Demos AI Agents, Engineers Are Fighting With Syslogs
I think this is one of the reason I have not been at many conferences, but rather to barcamps in the last years - you hear the status quo.
I think this is one of the reason I have not been at many conferences, but rather to barcamps in the last years - you hear the status quo.
Two KubeCons, One Conference: While Everyone Demos AI Agents, Engineers Are Fighting With Syslogs
KubeCon North America 2025 was actually two different events happening simultaneously in the same building. The first KubeCon lived on the exhibit floor. Every third booth featured some variation of…
www.distributedthoughts.org
November 24, 2025 at 1:56 PM
Two KubeCons, One Conference: While Everyone Demos AI Agents, Engineers Are Fighting With Syslogs
I think this is one of the reason I have not been at many conferences, but rather to barcamps in the last years - you hear the status quo.
I think this is one of the reason I have not been at many conferences, but rather to barcamps in the last years - you hear the status quo.
Dense Retrieval at Vinted: Nice blog introducing dense retrieval into a keyword driven search, starts with low recall sessions, a fine tuned CLIP model. retry strategies to switch between ANN and exact nearest neighbour search. Gets more interesting to the end.
Dense Retrieval
The Engineering Blog from Vinted. These are the voyages of code tailors that help create Vinted.
vinted.engineering
November 23, 2025 at 1:56 PM
Dense Retrieval at Vinted: Nice blog introducing dense retrieval into a keyword driven search, starts with low recall sessions, a fine tuned CLIP model. retry strategies to switch between ANN and exact nearest neighbour search. Gets more interesting to the end.
Grebedoc: github pages for as Open Source
Supports codeberg, uses Caddy, supports own domains, but not required.
Supports codeberg, uses Caddy, supports own domains, but not required.
Grebedoc
Static site hosting for Git forges
grebedoc.dev
November 22, 2025 at 1:56 PM
Grebedoc: github pages for as Open Source
Supports codeberg, uses Caddy, supports own domains, but not required.
Supports codeberg, uses Caddy, supports own domains, but not required.
How I fell in love with calendar.txt
TIL about calendar.txt. The trend to text-only (and versionable) continues. Seems that many other TODO/calendar tools are so convoluted nowadays, that simplification is key.
TIL about calendar.txt. The trend to text-only (and versionable) continues. Seems that many other TODO/calendar tools are so convoluted nowadays, that simplification is key.
How I fell in love with calendar.txt
How I fell in love with calendar.txt par Ploum - Lionel Dricot.
ploum.net
November 21, 2025 at 1:56 PM
How I fell in love with calendar.txt
TIL about calendar.txt. The trend to text-only (and versionable) continues. Seems that many other TODO/calendar tools are so convoluted nowadays, that simplification is key.
TIL about calendar.txt. The trend to text-only (and versionable) continues. Seems that many other TODO/calendar tools are so convoluted nowadays, that simplification is key.
A deep dive into BPF LPM trie performance and optimization
What a great read about a problem (sometimes you don't need a solution just yet) and how it was found and debug, including some data structure refresher.
What a great read about a problem (sometimes you don't need a solution just yet) and how it was found and debug, including some data structure refresher.
A deep dive into BPF LPM trie performance and optimization
This post explores the performance of BPF LPM tries, a critical data structure used for IP matching. It delves into the trie algorithm, presents benchmark data, and explains how the current kernel…
blog.cloudflare.com
November 20, 2025 at 1:56 PM
A deep dive into BPF LPM trie performance and optimization
What a great read about a problem (sometimes you don't need a solution just yet) and how it was found and debug, including some data structure refresher.
What a great read about a problem (sometimes you don't need a solution just yet) and how it was found and debug, including some data structure refresher.
Finished: Latency
Dives into the various concepts/ideas of reducing delay in software. More geared towards junior/mid level engineers who haven't had to touch latency/performance topics yet and want to get familiar with, explaining a lot of concepts.
Around 240 pages, nice rust based code samples.
Dives into the various concepts/ideas of reducing delay in software. More geared towards junior/mid level engineers who haven't had to touch latency/performance topics yet and want to get familiar with, explaining a lot of concepts.
Around 240 pages, nice rust based code samples.
November 19, 2025 at 1:56 PM
Finished: Latency
Dives into the various concepts/ideas of reducing delay in software. More geared towards junior/mid level engineers who haven't had to touch latency/performance topics yet and want to get familiar with, explaining a lot of concepts.
Around 240 pages, nice rust based code samples.
Dives into the various concepts/ideas of reducing delay in software. More geared towards junior/mid level engineers who haven't had to touch latency/performance topics yet and want to get familiar with, explaining a lot of concepts.
Around 240 pages, nice rust based code samples.
A hypothetical search engine on S3 with Tantivy and warm cache on NVMe
Great post describing the required steps to get a simple S3 based implementation of a search engine. There's dozens of more gotchas, but the basics are most important.
Great post describing the required steps to get a simple S3 based implementation of a search engine. There's dozens of more gotchas, but the basics are most important.
A hypothetical search engine on S3 with Tantivy and warm cache on NVMe
A simple architecture for BM25 search over object storage using immutable Tantivy shards, stateless indexers and query nodes, and local NVMe caching for sub-second queries.
www.shayon.dev
November 18, 2025 at 1:56 PM
A hypothetical search engine on S3 with Tantivy and warm cache on NVMe
Great post describing the required steps to get a simple S3 based implementation of a search engine. There's dozens of more gotchas, but the basics are most important.
Great post describing the required steps to get a simple S3 based implementation of a search engine. There's dozens of more gotchas, but the basics are most important.
Finally free of crutches, thanks to 3d printing I could at easily reach them after having a shower.
Measure, create design, print prototype. Took half a day. And code in a git repo.
Need to learn rounding edges, but we'll get there. Hoping no tools for post surgery equipment are involved.
Measure, create design, print prototype. Took half a day. And code in a git repo.
Need to learn rounding edges, but we'll get there. Hoping no tools for post surgery equipment are involved.
November 17, 2025 at 1:56 PM
Finally free of crutches, thanks to 3d printing I could at easily reach them after having a shower.
Measure, create design, print prototype. Took half a day. And code in a git repo.
Need to learn rounding edges, but we'll get there. Hoping no tools for post surgery equipment are involved.
Measure, create design, print prototype. Took half a day. And code in a git repo.
Need to learn rounding edges, but we'll get there. Hoping no tools for post surgery equipment are involved.
LLM for Java weekend: embabel - Agent framework for the JVM
Seems that quite a few early spring folks are involved in this one.
Seems that quite a few early spring folks are involved in this one.
GitHub - embabel/embabel-agent: Agent framework for the JVM. Pronounced Em-BAY-bel /ɛmˈbeɪbəl/
Agent framework for the JVM. Pronounced Em-BAY-bel /ɛmˈbeɪbəl/ - embabel/embabel-agent
github.com
November 16, 2025 at 1:56 PM
LLM for Java weekend: embabel - Agent framework for the JVM
Seems that quite a few early spring folks are involved in this one.
Seems that quite a few early spring folks are involved in this one.
LLM for Java weekend: agent-o-rama
An end-to-end LLM agent platform for Java and Clojure for building, tracing, testing, and monitoring agents with integrated storage and one-click deployment. Inspired by LangGraph/LangSmith.
An end-to-end LLM agent platform for Java and Clojure for building, tracing, testing, and monitoring agents with integrated storage and one-click deployment. Inspired by LangGraph/LangSmith.
GitHub - redplanetlabs/agent-o-rama: An end-to-end LLM agent platform for Java and Clojure for building, tracing, testing, and monitoring agents with integrated storage and one-click deployment. Inspired by LangGraph/LangSmith.
An end-to-end LLM agent platform for Java and Clojure for building, tracing, testing, and monitoring agents with integrated storage and one-click deployment. Inspired by LangGraph/LangSmith. - redp...
github.com
November 15, 2025 at 1:56 PM
LLM for Java weekend: agent-o-rama
An end-to-end LLM agent platform for Java and Clojure for building, tracing, testing, and monitoring agents with integrated storage and one-click deployment. Inspired by LangGraph/LangSmith.
An end-to-end LLM agent platform for Java and Clojure for building, tracing, testing, and monitoring agents with integrated storage and one-click deployment. Inspired by LangGraph/LangSmith.
Finished: Modern concurrency in Java
Nice 300 page introduction into Virtual Threads and Structured Concurrency, how those two work together. As I didn't have time to delve into both topics so far, this was a great refresher.
Nice 300 page introduction into Virtual Threads and Structured Concurrency, how those two work together. As I didn't have time to delve into both topics so far, this was a great refresher.
November 14, 2025 at 1:56 PM
Finished: Modern concurrency in Java
Nice 300 page introduction into Virtual Threads and Structured Concurrency, how those two work together. As I didn't have time to delve into both topics so far, this was a great refresher.
Nice 300 page introduction into Virtual Threads and Structured Concurrency, how those two work together. As I didn't have time to delve into both topics so far, this was a great refresher.
Reposted by Alexander Reelsen
After a year of work, we are happy to share that Spring Framework 7.0 GA is now available! spring.io/blog/2025/11...
Time to celebrate, get a bit of rest and help the team to prepare Spring Boot 4.0 GA release planned November 20th 😊
#spring #java
Time to celebrate, get a bit of rest and help the team to prepare Spring Boot 4.0 GA release planned November 20th 😊
#spring #java
Spring Framework 7.0 General Availability
Level up your Java code and explore what Spring can do for you.
spring.io
November 13, 2025 at 5:40 PM
After a year of work, we are happy to share that Spring Framework 7.0 GA is now available! spring.io/blog/2025/11...
Time to celebrate, get a bit of rest and help the team to prepare Spring Boot 4.0 GA release planned November 20th 😊
#spring #java
Time to celebrate, get a bit of rest and help the team to prepare Spring Boot 4.0 GA release planned November 20th 😊
#spring #java
Another day another query language. Querying JSON with JSON query language, making the queries look like JSON arrays.
Might make sense, if all you have is JSON. The question is, if that is the right way of querying or just a backing syntax for an UI editor.
Might make sense, if all you have is JSON. The question is, if that is the right way of querying or just a backing syntax for an UI editor.
JSON Query - a small, flexible, and expandable JSON query language
JSON Query - a small, flexible, and expandable JSON query language
jsonquerylang.org
November 13, 2025 at 1:56 PM
Another day another query language. Querying JSON with JSON query language, making the queries look like JSON arrays.
Might make sense, if all you have is JSON. The question is, if that is the right way of querying or just a backing syntax for an UI editor.
Might make sense, if all you have is JSON. The question is, if that is the right way of querying or just a backing syntax for an UI editor.
oxdraw - diagrams as code using mermaid but with adding the ability for exact positioning/coloring.
Nice idea, also there is typst integration.
Nice idea, also there is typst integration.
GitHub - RohanAdwankar/oxdraw: Diagram as Code Tool Written in Rust with Draggable Editing
Diagram as Code Tool Written in Rust with Draggable Editing - RohanAdwankar/oxdraw
github.com
November 12, 2025 at 1:56 PM
oxdraw - diagrams as code using mermaid but with adding the ability for exact positioning/coloring.
Nice idea, also there is typst integration.
Nice idea, also there is typst integration.
Super interesting post about fly.io state management software.Not a big consensus driven distributed system or centralized, but using SWIM and sqlite with CRDTs. Great to learn to see such design decisions play out on such a big network.
fly.io/blog/corrosi...
fly.io/blog/corrosi...
Deploy app servers close to your users · Fly
Over 3 million apps have launched on Fly.io, leveraging global Anycast load-balancing, zero-config private networking, hardware isolation, instant WireGuard VPN connections, and push-button…
fly.io
November 11, 2025 at 1:56 PM
Super interesting post about fly.io state management software.Not a big consensus driven distributed system or centralized, but using SWIM and sqlite with CRDTs. Great to learn to see such design decisions play out on such a big network.
fly.io/blog/corrosi...
fly.io/blog/corrosi...
How fast is java? Teaching an old dog new tricks
Nice blog post about Java Vector API to improve rendering using SIMD.
Nice blog post about Java Vector API to improve rendering using SIMD.
how fast is java? Teaching an old dog new tricks
Java, the language everyone loves to hate. Long has it garnered the reputation of a stagnant, obtuse, bloated beast only used by those who have no other choice because some enterprise corporate…
dgerrells.com
November 9, 2025 at 1:56 PM
How fast is java? Teaching an old dog new tricks
Nice blog post about Java Vector API to improve rendering using SIMD.
Nice blog post about Java Vector API to improve rendering using SIMD.
Homerow - Keyboard shortcuts for every button in macOS
successor to vimac, bringing vimium to osx. Is anyone using this? What is the difference to shortcat?
successor to vimac, bringing vimium to osx. Is anyone using this? What is the difference to shortcat?
Homerow | Keyboard shortcuts for every button in macOS
Homerow lets you navigate macOS with more keyboard and less mouse.
www.homerow.app
November 8, 2025 at 1:56 PM
Homerow - Keyboard shortcuts for every button in macOS
successor to vimac, bringing vimium to osx. Is anyone using this? What is the difference to shortcat?
successor to vimac, bringing vimium to osx. Is anyone using this? What is the difference to shortcat?
Achievement unlocked: Added a cover slide using a terminal with figlet to my no-slides #elasticon presentation showing ES|QL to look into three years of solar data.
A part of the demo has also been written down in a blog post. See spinscale.de/posts/2025-1...
A part of the demo has also been written down in a blog post. See spinscale.de/posts/2025-1...
November 7, 2025 at 1:56 PM
Achievement unlocked: Added a cover slide using a terminal with figlet to my no-slides #elasticon presentation showing ES|QL to look into three years of solar data.
A part of the demo has also been written down in a blog post. See spinscale.de/posts/2025-1...
A part of the demo has also been written down in a blog post. See spinscale.de/posts/2025-1...
Reposted by Alexander Reelsen
🛠️ If your team has issues to work through:
We do an exercise at offsites called Elephants, Tigers & Paper Tigers.
- Elephants are things that the group isn’t talking about but needs to
- Tigers are things threatening the team, risks
- Paper tigers are things that seem like risks, but aren’t
We do an exercise at offsites called Elephants, Tigers & Paper Tigers.
- Elephants are things that the group isn’t talking about but needs to
- Tigers are things threatening the team, risks
- Paper tigers are things that seem like risks, but aren’t
November 6, 2025 at 1:29 PM
🛠️ If your team has issues to work through:
We do an exercise at offsites called Elephants, Tigers & Paper Tigers.
- Elephants are things that the group isn’t talking about but needs to
- Tigers are things threatening the team, risks
- Paper tigers are things that seem like risks, but aren’t
We do an exercise at offsites called Elephants, Tigers & Paper Tigers.
- Elephants are things that the group isn’t talking about but needs to
- Tigers are things threatening the team, risks
- Paper tigers are things that seem like risks, but aren’t