Authoring a Problem of the Day

Each problem is one JSON file containing everything: the statement, the samples, the hidden tests, and the checker. These files are the authoring source: they're git-ignored and loaded into the database with the seed script (below), so the hidden tests never enter the repo. Keep them somewhere private to the setting team.

Flow

1. Copy an existing file as a starting point.
2. Name it YYYY-MM-DD-kebab-title.json, where the date is the day it should go live. Future-dated problems are not served by the app — the statement, its samples, and its hidden tests stay invisible until that date arrives — so you can queue problems ahead of time.
3. Validate: npm run challenges:validate.
4. Seed it into the database: npm run challenges:seed (local) or npm run challenges:seed -- --target remote (production D1). Publishing is a database write — no redeploy — and it releases automatically at the top of its date.

Schema

Field	Required	Notes
schemaVersion	–	Integer. Currently 1.
slug	–	Lowercase letters/digits/hyphens. Defaults to the filename; if set, must match it.
title	✓	Display title.
difficulty	–	One of Easy, Medium, Hard, Unrated.
tags	–	Array of strings.
date	✓	YYYY-MM-DD, a real calendar date. Release day.
timeLimit	–	e.g. "1s", "500ms". Enforced by the judge (TLE).
memoryLimit	–	Display only for now, e.g. "256 MB".
author	–	Credit line.
statement	✓	Markdown. Inline code and fenced blocks render.
inputFormat / outputFormat / constraints	–	Markdown.
samples	✓	≥1 { input, output, explanation? }. Shown to solvers.
tests	✓	≥1 { input, output }. Hidden — never sent to the client.
checker	–	{ "type": "token" | "exact" | "float", "epsilon"? }. Defaults to token.

There is no points field — scoring is server-side: the live Problem of the Day is a speed bounty (finish order), and a past problem solved for practice earns a flat base score.

Checkers

• token (default): whitespace-insensitive token-by-token match. Use for most integer/string answers.
• exact: byte-for-byte (trailing newlines ignored). Use when spacing matters.
• float: token match with numeric tolerance epsilon (default 1e-6).

Validate & seed locally

npm run challenges:validate
npm run challenges:seed