A version control for your beliefs.
Most beliefs are held at unstated confidence levels, never written down, and revised only when social pressure demands it. When people do try to update, the anchoring effect pulls the new estimate towards the old one, regardless of what evidence has arrived.
Sententia is a single-file browser application that records beliefs as probabilistic credences on a 0-to-1 scale and surfaces them for blind review: you submit a new estimate before your previous value is revealed, breaking the anchoring loop. Everything stays in the file itself, with no server and no account.
Evidence-based giving, measured.
Most donors can tell you exactly how much they gave last year. Few can tell you what it accomplished. The infrastructure most people reach for is a spreadsheet for amounts, GiveWell open in a browser tab, a rough mental estimate of pledge compliance. This tracks spending precisely and impact not at all.
Meridian is a single-file giving dashboard that runs entirely in your browser. It computes expected impact in DALYs for each charity in your portfolio, anchored to GiveWell's benchmark, and combines this with donation history, UK Gift Aid, pledge tracking, and cause allocation in one view. No data leaves your machine.
Reason through difficult moral decisions under ethical uncertainty.
Difficult moral decisions are often difficult not because the facts are uncertain, but because different ethical frameworks point towards different conclusions. The usual response is to unconsciously shift between those frameworks until one justifies the answer we were already inclined to choose.
Deliberatio is designed to make that harder. Built around Will MacAskill's Maximising Expected Choice-Worthiness principle, it lets you select the moral theories you take seriously, assign a credence range to each, evaluate every option before seeing any outcome, and it then combines those assessments into a transparent recommendation. Deliberatio includes twenty-two theories across seven ethical families, introduces structured tie-breakers when results are close, and stores all data locally in your browser.