CircuitWall Consultancy

Expert Java, Spring, JVM performance tuning, big data, real-time processing and machine learning consultancy by Andrew Wu in Stockholm, Sweden.


Blog Posts


Technical articles and insights about cloud computing, distributed systems, and software engineering

· 6 min read

Day 1 of Jarela: Building My Own Lightweight Claude-Code-ish Replacement

I got tired of how complex my openclaw setup had gotten — too many tools, too many integrations I never used. So I started building a small LangGraph-based GUI for multi-agent workflows on my own laptop. This is day 1: 31 commits, a lot of streaming/reconnection pain, and three different GitHub Copilot auth flavors to untangle.

LangGraphClaude CodeMulti-AgentNext.js
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· 7 min read

Kafka 2: Multi Datacenter Setup

Organizations typically consider multi-datacenter setups for two main reasons: Business expansion into different geographical regions Enhanced reliability requirements that take …

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· 8 min read

Kafka 1: Basics

As a consultant, admitting “I don’t know” can be challenging. A few months ago, I began working as a DevSecOps engineer on a large Kafka (Confluent) installation …

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