Compsci

Not Before Time is a public broadcast facility built on existing technology. Not Before Time guarantees that information: will not be readable before a certain future time (no early reading) was not sealed before a certain past date and time (no earlier sealing) was not electronically signed before a certain time (no late denials) These guarantees support human rights, democracy and business. Novel features of Not Before Time are: Time locked information is the opposite of the trend for all information to be available instantly, everywhere. The three guarantees are supplied to ordinary users using their everyday software on their existing devices. The mechanism and its novel new applications are easily explained to non-technical people, perhaps including you. Much of NBT is already running in a demonstration called quicknet. There are open research questions to be addressed before there can be a stanardised, global trust about future time, but the principles seem clear. ...

I have used Cloba on isolated and small personal machines for many years. When I want something that is secure, distributed and generally more modern there are plenty of options I have tried. One I am looking into is Atuin ↗ whose name I hope refers to The Great A’Tuin ↗. Recording all bash commands, simple & insecure There are three components: bash.logging, a bash script to initially set up the logging tool in a login session syslog, set up to receive a message every time there is a new bash prompt /var/log/commandline.log, containing all lines typed at all bash prompts Here’s how it works: ...

The image below shows a home page served by a Palm Pilot ↗, once a popular handheld device. The Inetd linux.conf.au LiveCD immersed conference attendees in the talks by letting them run the speakers’ software. We gave all attendees at the 2004 linux.conf.au in Adelaide a bootable CD containing a heterogeneous network of virtual computers running different operating systems, pre-configured with the speakers’ software. I built the Inetd linux.conf.au LiveCD ↗ by modifying Knoppix ↗. Screenshots were in my Tunnelling Hardware over SMTP ↗, selected for a re-run as one of the “Best Of” papers. In 2026 we could update this by running an entire network in the browser with JSLinux by Fabrice Bellard ↗, a fast browser-based emulator developed and optimised over many years. ...

The problem: Most computer users manually save versions of files with names like Presentation-2027-Jan-11, followed later by Presentation-2027-Jan-11-UPDATED and Presentation-2027-For-Sally-Only, perhaps with Presentation-panic-edits-before-event. This is manual versioning, and even people who stick strictly to a naming convention still get confused at times. Some applications append .bak or prefix ~ to create their own backups, and then occasionally an automatically-created TMP or $tmp$ file can really save the day, and so on. Then when it comes time to clean up and organise a filesystem, everyone hesitates. Am I really sure there is not useful work in each of those ten versions? Which ones do I need to keep? So, we usually keep them all. After all, storage is cheap. ...

In responding to a recent security problem I had to consider the idea of intent in computer software, so I looked to see what Margaret Hamilton ↗ has to say. Hamilton proved her ideas spectacularly during the first Apollo moon landing in 1969. A hardware failure generated unexpected errors ↗, but the software coped by running the highest-priority tasks despite the barrage of errors, preventing an abort seconds before landing on the surface. The abort procedure was dangerous, so she prevented tragedy in multiple ways. Hamilton’s observations on reliable and secure systems remain highly relevant. Despite spending four decades telling the world how to make reliable software very few people have put her ideas into practice, and fewer in the integrated manner she promoted. ...

AI is slow, and Agentic AI ↗ is even slower. I develop an MCP server ↗ that generates PDF documents, and I work with the Agentic Perseverance Composition Engine daily. Tasks that take maybe 5 microseconds on an operating system (eg, does a file called Things-to-Do exist?) can take a million times longer, between 2 and 5 seconds, because each operation requires multiple round trips to a remote LLM (often with timeouts.) It’s a young, unstable stack, comparable in maturity to early MS DOS or the Apple ][. When AI gets hold of your data via an MCP server it can do interesting things, but it is not put together well. ...

The detail of the GDPR and its implied computer science contain a solution for sharing secrets according to law. This continues to be true in 2026, as the Digital Omnibus Regulation ↗ takes shape. Executive Summary The GDPR sets up a conflict in trust between companies in particular circumstances, which can only be resolved by using the automation of a cryptographic audit trail with particular properties as described below. Problem Statement Under the EU’s GDPR ↗ law virtually every company is a Controller, and virtually all Controllers use at least one Processor. When a Processor is engaged, the GDPR requires that a contract is signed with the very specific contents spelled out in clause 3 of Article 28. The GDPR requires that Controllers and Processors cooperate together in order to deliver data protection, and this cooperation needs to be very carefully managed to maintain the security and other guarantees that the GDPR also requires. That’s what this mandatory contract is intended to achieve. ...

When Linux was a Struggling Challenger 💡 Key Point This is a 2026 restoration of my (Dan Shearer’s) 1998-2001 guide, preserved at archive.org ↗. Links have been updated to point to the archives where possible. In 1999 I joined my first startup, Linuxcare in San Francisco. The Linuxcare story is a quintessential United States dot-com bubble narrative, featuring a famous venture capital fund, massive growth, a failed IPO, and a fancy new ex-IBM CEO resigning under a cloud. Founded in 1998, Linuxcare aimed to be the “0800 number for Linux”. So close! As Samba co-founder I had experience migrating corporates away from Microsoft servers, and brought my how-to with me to Linuxcare. Microsoft was extremely sensitive to documents like this, and downright allergic to the word ‘replace’. I found out years later this article was targeted for disinformation in key Microsoft accounts. This was a battle of narratives as well as monopolistic behaviour and technical facts. More than a quarter of a century later, the technical content has aged fairly well. Quite a lot of the migration solutions were easier than they would be now, because quality of the Microsoft/Windows solutions was so poor. Many of the monopolistic facts remain much the same, which is slightly depressing. But some things were unimaginable in 1999: Samba both succeeded and failed but Samba (or something like it) may have another chance The EU is serious about alternatives Exciting times! But not for Linuxcare, which had spectacular human failures and quietly collapsed from 300 staff to 3 within a couple of years. ...

The Fossil ↗ source code management system is the most fully-featured alternative to Git, and has decades of development and testing starting in 2007. After helping Fossil make some changes I now use Fossil for several projects. I also use Git extensively on various software forges (but not GitHub unless I must). Mercurial ↗ is actively maintained as described in this FOSDEM 2026 talk ↗ but is rarely chosen for new projects today. So if we stick to supported production tools that get new users it’s either Fossil or Git. Git use is vastly greater than Fossil’s, but on features, portability, longevity and developer response time Fossil tends to lead Git. ...

LumoSQL ↗ protects data on mobile phones and other computers using a new data storage technology which is highly compatible with most existing devices. The first part of this gives better robustness in the case of a powerloss or other crash, and at-rest encryption. Most apps have no encryption at all so this is a great improvement. With the second part of LumoSQL being developed now, the device owner decides who can read or change their data down to the level of individual rows if they choose. This decision continues to be enforced even after it has been copied off the phone to (for example) a bank or dating or insurance company for processing with their in-house database software. Today, device owners are rarely in control of the privacy of their own data, despite the many privacy laws. If a phone is separated from its owner, LumoSQL data rows cannot be read without the consent of either the phone owner or someone to whom the phone owner has granted access even if the phone has been unlocked. These controls are fine-grained, meaning different levels of permission can be granted. ...