Allegro Tech Blog
blog.allegro.tech · Company blog · on HN since 2015
Allegro Tech Blog is the engineering blog of Polish e-commerce company Allegro, covering Kafka, Go, Kotlin, databases, and cloud costs.
What HN saysHN links it for engineering write-ups like the fast Go cache service post, and commenters share their own Kotlin versus Java experience.
38HN people shared it
3linked it in comments
65stories submitted
1.0Kstory points
5 months agolast shared
2015people per year2026
Most-shared posts
- 1Unlocking Kafka's Potential: Tackling Tail Latency with eBPF6 people · 68 points · first shared 2024 · discussion on HN
- 2Beyond the Code – An Engineer's Battle Against Knowledge Loss5 people · 10 points · first shared 2023 · 1 comments on HN
- 3Writing a very fast cache service with millions of entries in Go3 people · 182 points · first shared 2016 · 88 comments on HN
- 4How does a B-tree make queries fast?2 people · 271 points · first shared 2023 · 77 comments on HN
- 5From Java to Kotlin and Back Again2 people · 192 points · first shared 2018 · 196 comments on HN
- 6Ten Years and Counting: My Affair with Microservices2 people · 97 points · first shared 2024 · 51 comments on HN
- 7Reducing the cost of a single Google Cloud Dataflow Pipeline by Over 60%2 people · 10 points · first shared 2024 · 2 comments on HN
- 8Hitting the wall Marathon2 people · 6 points · first shared 2017 · discussion on HN
- 9Postmortem: outage in a large distributed system2 people · 4 points · first shared 2018 · 2 comments on HN
- 10Domino – financial forecasting in the age of global pandemic2 people · 4 points · first shared 2021 · discussion on HN
- 11A comedy of errors. Debugging Java memory leaks2 people · 2 points · first shared 2018 · discussion on HN
- 12Hermes – A message broker built on top of Kafka1 people · 125 points · first shared 2019 · 54 comments on HN
- 13Estimating the cache efficiency using big data1 people · 7 points · first shared 2017 · discussion on HN
- 14Migrating a heterogenous system to Service Mesh at Allegro.pl1 people · 6 points · first shared 2020 · discussion on HN
- 15Finite-state machines made easy1 people · 4 points · first shared 2021 · discussion on HN
What HN people wrote when they linked it
mkosmul · 2025-12-23
Allegro Tech Blog: https://blog.allegro.tech/
brabel · 2021-02-13
I've been using Kotlin in the backend since 1.0 (4 years now??) and it's great, but it does have a few small annoyances. We still have most of our codebase in Java and routinely, we create new Java code instead of Kotlin for everything, interestingly enough (mostly because when a module is already written in Java, it's mostly a source of confusion to add a few Kotlin files - so we tend to only use Kotlin when creating new modules that are fully Kotlin). Also, some of our developers just don't seem to have enough abstraction power for the higher level of code you can write in Kotlin (specially when you start using things like Kotlin builders to make code "prettier", or just abust a little bit the "everything is an expression" feature to completely avoid separete statements - e.g. functions without braces).
People moving from Kotlin back to Java is not unheard of: https://blog.allegro.tech/2018/05/From-Java-to-Kotlin-and-Back-Again.h…
reinhardt1053 · 2019-12-23
Blog post that describes the implementation:
https://allegro.tech/2016/03/writing-fast-cache-service-in-go.html