Production-grade, privacy-first patterns for moving library catalog, holdings, and circulation data between legacy MARC systems, BIBFRAME-aware discovery layers, and modern ILS APIs.
🌐 Read it live at librarycatalog.org →
librarycatalog.org is a deep, hands-on reference for the engineers who keep library data flowing. It is written for library technology staff, ILS administrators, public-sector developers, and the Python automation engineers who build and operate catalog and circulation pipelines in production.
Every page favors deterministic, idempotent, and auditable pipelines over clever abstractions. The code is real: typed signatures, context managers, explicit error handling, structured logging, quarantine queues, and compliance checkpoints — the things that matter when a nightly sync fails at 2 a.m. and a patron's privacy is on the line.
Across 51 in-depth guides (~148,000 words), the site covers the full journey of a record — from a legacy MARC export, through validation and transformation, into a modern ILS, out to self-service kiosks and consortial partners, and safely into audit-ready reporting.
The material is organized into four tightly-scoped areas:
| Area | What it covers |
|---|---|
| Core Architecture & Catalog Standards | Domain isolation and data-flow topology, MARC21 ↔ BIBFRAME interoperability, ILS schema translation, idempotent sync patterns, and privacy-by-design at the pipeline level. |
| Catalog Ingestion & ILS Sync Pipelines | Streaming MARC parsing with pymarc, async batch processing on Celery/RQ, REST polling with backoff and 429 handling, schema validation, and dead-letter recovery. |
| Patron Validation & Privacy Data Routing | Zero-trust patron pipelines: identity resolution, PII masking, FERPA/GDPR-aligned routing, retention enforcement, right-to-erasure, and audit-ready compliance reporting. |
| Circulation Protocols & Interoperability | SIP2 and NCIP integration, Z39.50/SRU search retrieval, RFID self-check synchronization, and consortial resource-sharing workflows — including a practical SIP2-vs-NCIP decision guide. |
- Copy-adaptable, production Python — not toy snippets. Real exception types, retry logic, and profiling notes.
- Compliance woven in, not bolted on — FERPA, GDPR, and state library-record confidentiality rules appear where the code touches patron data, with masking, hashing, and retention checkpoints.
- Diagnostic reference anatomy — every guide reads the way engineers work: scan the spec, validate assumptions, adapt working code, then check the compliance edge cases.
- Hand-authored diagrams — original, accessible inline SVG data-flow and sequence diagrams, theme-aware and screen-reader friendly.
- Tightly interlinked — every concept links to the guide that explains it, so you are always one click from the detail you need.
- Static site generated with Eleventy (11ty) — no client-side framework, fast by default.
- Hand-written CSS with a warm, accessible, WCAG-AA color system; a tiny vanilla-JS enhancement layer for code copy buttons and syntax highlighting.
- Structured data (JSON-LD:
TechArticle,BreadcrumbList,Organization) on every page. - Deployed on Cloudflare Pages.
▶ Start reading at librarycatalog.org
A few high-value guides to start with:
- Parsing MARC Records with pymarc
- SIP2 vs NCIP: Choosing the Right Circulation Protocol for Your ILS
- Implementing GDPR Right-to-Erasure in Circulation Data
- Designing an Append-Only Audit Log Schema
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