Circulation desk, cataloging workbench, acquisitions office, serials room, and public catalog all share one roof in Koha, an open-source library system that scales across school libraries, branch networks, and consortia. Staff search the catalog with facets for availability, authors, holding libraries, and item types, then open a record to see its cover, subjects, classification numbers, and every copy with its call number, status, and barcode. Catalogers edit MARC 21 or UNIMARC records field by field, copy records in via Z39.50 and SRU searches, and link authorities automatically. At the desk, staff check out, check in, and renew items, work with holds, bookings, and claims, and see overdue warnings and outstanding charges beside each patron. Circulation and fine rules vary by library, patron category, and item type. Acquisitions handles vendors, baskets, budgets, and funds. Serials track subscriptions and issue receiving. A guided report wizard, SQL reports, and statistics wizards summarize circulation and collections. Patrons search the public catalog, place holds, save lists, tag and rate titles, and suggest purchases. Staff tools design notices and slips, print patron cards, set holiday calendars, and import or batch-edit patrons. SIP2 serves self-checkout kiosks, OAI-PMH sets share records, and a REST API exposes patrons, holds, checkouts, and biblios. Lending continues during outages with offline circulation. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.