Building an open CIS — Article Series on Implementing a Minimal CIS with EHRBase

Implementation Apps
, , ,
1

Hi there,

I’ve been documenting my experience building a minimal Clinical Information System on EHRBase, and wanted to share the resulting article series with the community.

Repository: github.com/platzhersh/open-cis

The Series

  1. Part 1: Introduction - Two-level modeling explained, the Lego analogy for archetypes/templates, and project motivation.

  2. Part 2: The Clinical Modeling Stack - ADL, BMM, OPT walkthrough, and understanding archetype node IDs.

  3. Part 2b: FLAT Format Deep Dive - Practical differences between EHRBase and Better Platform: Content-Type headers, template ID handling in paths, validation behavior, and datatype syntax variations. This one documented several gotchas I wish I’d known earlier.

  4. Part 3: Going SDK-less (coming soon) - Direct REST integration with EHRBase using Python/FastAPI. What’s straightforward (EHR creation, AQL queries) vs. what’s painful (composition building without type safety).

  5. Part 4: The SDK Landscape (coming soon) - Survey of Java (Archie, EHRBase SDK, CaboLabs), JavaScript/TypeScript options, and the Python gap.

Stack

Vue 3 + TypeScript + shadcn-vue
    ↓ REST
FastAPI + Python + Pydantic
    ↓                ↓
PostgreSQL       EHRBase
(app data)    (clinical data)

Separate databases for application state vs. clinical data - mirroring how production deployments often work.

Looking for Feedback

Particularly on the FLAT format findings (Part 2b) - did I miss nuances? And for those working on Python tooling: what would make a Python SDK actually useful for your workflows?

Happy to answer questions or discuss implementation details.

Cheers

Chris

4 Likes
2

I have only had a quick look but I think you have done a great job. For a next step I woukd include a fhir terminology server and hook it up to the cdr. Terminology handling is pretty well minimal for any clinical system.

3 Likes
3

Thank you @ian.mcnicoll ! I will dive into this on another rainy weekend probably :smiley: (or when it becomes more current at work)