Introduction
Coffer is a self-hosted coin collection management application. It tracks your physical coin holdings, calculates real-time precious metal valuations, and integrates with the Numista catalog for collector market prices.
Why Coffer?
Section titled “Why Coffer?”Most coin collection tools are either paid SaaS platforms, outdated desktop apps, or simple spreadsheets. Coffer fills the gap as a modern, self-hosted web application that gives you:
- Real-time metal valuations — Gold, silver, and platinum prices updated every 5 minutes from live forex data
- Collector value tracking — Market prices pulled from Numista for graded coins
- Portfolio-level analytics — Aggregate value, historical charts, and metal composition breakdowns
- Full data ownership — Everything runs on your hardware via Docker
What it tracks
Section titled “What it tracks”Each coin in your collection stores:
| Field | Description |
|---|---|
| Title | Coin name or description |
| Year | Minting year |
| Country | ISO 3166-1 country code |
| Currency | ISO 4217 currency code |
| Denomination | Face value |
| Metal type | Gold, silver, platinum, or nickel |
| Weight & purity | For metal value calculation |
| Grade | GOOD through PROOF (8 grades) |
| Type | Bullion, commemorative, standard circulation, etc. |
| Numista ID | Links to the Numista catalog for images and prices |
| Images | Obverse and reverse photos (auto-fetched or manual) |
How valuations work
Section titled “How valuations work”Coffer calculates two types of value for each coin:
-
Metal valuation —
weight × (purity / 1000) × current price per gram. Updated from live forex data (Swissquote) every 5 minutes on weekdays. -
Collector valuation — Market price from Numista, tied to the specific issue (year + mint mark) and grade. Can be an exact price or a min/max range.
Both are tracked historically, so you can see how your collection’s value has changed over any timeframe.
Project structure
Section titled “Project structure”Coffer has a Kotlin/Spring Boot backend, an Angular frontend, and a Docker Compose deployment configuration. Pre-built container images are published to GitHub Container Registry — to self-host Coffer, see the coffer-deploy repository.