Breviarium 🙏🏼

Open source Liturgy of the Hours, collaborate to build the best Divine Office library!

Generates liturgical content and calendars of the Roman Rite of the Roman Catholic Church.
Supports Node v18+, Modern Browsers (desktop and mobile).

Quickstart setup

1. Install with your prefered package manager

npm install breviarium

pnpm install breviarium

yarn add breviarium

2. Import and use the library to retrieve the desired data (ex: Laudes) Usage:

const breviarium = new Breviarium(useDateStore().getCurrentDate);

// get laudes for today
await breviarium.getLaudes().then((data) => { console.log("laudes data:", data) })

const breviarium = new Breviarium(useDateStore().getCurrentDate);

// get laudes for a given date (example for 2025-7-30)
await breviarium.getLaudes(new Date(2025, 6, 30)).then((data) => { console.log("laudes data:", data) })

Function Documentation

Liturgy of the hours: functions to retrieve the information of the library:

Function	Parameters	Description	Example Call
getLaudes	date?: Date	Returns the Laudes prayer for a given date.	prayers.getLaudes();
getVesperae	date?: Date	Returns the Vesperae prayer for a given date.	prayers.getVesperae(new Date(2025, 1, 17));
getOfficium	date?: Date	Returns the Officium prayer for a given date.	prayers.getOfficium();
getTertia	date?: Date	Returns the Tertia prayer for a given date.	prayers.getTertia();
getSexta	date?: Date	Returns the Sexta prayer for a given date.	prayers.getSexta(new Date());
getNona	date?: Date	Returns the Nona prayer for a given date.	prayers.getNona();
getCompletorium	date?: Date	Returns the Completorium prayer for a given date.	prayers.getCompletorium();
getMissaleLectiones	date?: Date	Returns the Mass readings prayer for a given date.	prayers.getMissaleLectiones();
getEvangelium	date?: Date	Returns the Gospel text for a given date.	prayers.getEvangelium(new Date(2025, 5, 1));

Test

To run the test suite (with vitest), execute:

To run the app:

# linux and mac users:
make test
# for windows users:
npm run test