Market Making 101: How to Get Paid for Being Patient
A practical tutorial on passive market making — the trading method where you never predict the market, never chase a chart, and earn your money from the width of the spread.
Notes on software engineering
Things I learn
building systems
Distributed systems, workflow orchestration, PostgreSQL and the things I learn building durable software.
- 2026
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9 min read
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Futex: Silence is a denial
On building a human-in-the-loop control plane for agents that can spend money, grant access, and delete things. — 0.
19 min read -
RevolutX, Good, Bad, Ugly
A technical and product review of Revolut's crypto exchange, from building an automated market maker on it — the documented behaviour, the undocumented behaviour, the arithmetic that decides…
16 min read -
RunFlow: building a place to run code you don't trust
- I should declare my position up front, because it colours everything below. I did not set out to build a container platform.
12 min read -
Building TokenGate: a meter that would rather overcharge you than lose the count
Bias declared up front, same as last time: TokenGate is mine. I designed it, I wrote it, I run it in production, and I have every commercial incentive to tell you it is wonderful.
13 min read -
I Built My Own CI/CD, and the Interesting Part Wasn't the CI
On replacing GitHub Actions with something that owns almost nothing — and why that turned out to be the whole point.
21 min read -
Nature’s Pinocchios
disclaimer : AI helped me to generate most parts of the text and make it more readable. The Deceptive Nature of the Animal Kingdom: Instinct or Intent?
4 min read - 2025
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The Shape-Shifter: Why AI-Driven Polymorphic Attacks Keep Me Up at Night
We used to have it relatively easy. When I first started paying attention to cybersecurity, malware was static. It was a specific file, with a specific "fingerprint" (hash).
2 min read -
Highway Workflow Engine
The Bank-Grade, Postgres-Native Workflow Engine. Highway is a durable workflow orchestration engine designed for systems where data integrity is non-negotiable .
3 min read -
Zero Dependency Context Aware Command Line Project Management
Code Agent Optimised Issue Tracker / Zero Dependency Context Aware Command Line Project Management 🤖 + = 🚀 I built a command-line issue tracking system for software development projects.
1 min read -
issue.db / your issue tracker in your repo
So this was this week's side project: issue-queue.readthedocs.io here is the workflow: I hope you find it useful.
1 min read -
Authorisation for Humans - A complete RBAC library
Auth is a RBAC lib I started back in 2015, when I badly needed something simple and quick. Since then, developers have download it hundreds of thousands of times, indeed, Pyhton Software Organisation…
1 min read -
Castle vs. Moat
This is the classic "Castle vs. Moat" debate in security architecture. While Docker provides a Moat (isolation from the host machine), the Sandbox provides the Code of Conduct (rules for what happens…
1 min read -
Circuit breakers needs durable state
I just noticed that I have missed a big point during the design phase of my workflow engine! I Leonard that, proper circuit breakers must have a durable state in a proper database.
1 min read -
Critical lessons from implementing a highly complex workflow system
- Transaction Boundaries are Sacred: When spawning child tasks, the parent MUST commit its transaction before children become visible to workers.
1 min read -
Building Datashard: Solving Data Corruption in High-Concurrency ML Workflows
I've been working on Highway, a Strict Atomic Workflow Management System that handles massive amounts of log data from multiple concurrent processes.
2 min read -
A new Article about what I am doing
I just published this article medium.com/@erlang/bank-grade-workflow-engine
1 min read -
A comparison of advanced workflow engines
Feature Highway Workflow Engine DBOS (from Demos) Apache Airflow Tork — — — — — Core Philosophy Decoupled Library . A resilient engine you integrate into your app. Integrated Framework .
2 min read -
A complete workflow domain-specific language - Highway DSL
rodmena-limited.github.io/highway dsl/ link to specs are here
1 min read -
How to run processes in with limited resources in Linux (no Docker needed)
It's super powerful and simple:
1 min read