16 posts tagged with "architecture"

One of OHDSI's greatest strengths is database agnosticism. The HADES ecosystem — via SqlRender and DatabaseConnector — lets researchers write analyses once and run them against SQL Server, PostgreSQL, Oracle, Snowflake, BigQuery, and seven other platforms without modification. Today, Parthenon achieved full parity with that capability: all 12 HADES-supported database dialects are now covered across both the PHP SQL translator and the R runtime.

Eighteen Docker services. Three environment files. A reverse proxy with auto-TLS. Database admin GUI. Container management dashboard. Enterprise SSO. And if you want the full stack? One command:

python3 install.py --with-infrastructure

This is the story of how we built Acropolis — the infrastructure layer that turns Parthenon from a research application into a production platform — and what we learned when we decided to ship it inside the same repository.

Every platform has a weak link. For Parthenon, it was the R container.

PHP handled 200 concurrent API requests without breaking a sweat. Python served AI inference with async workers. PostgreSQL managed million-row queries across six schemas. Redis cached sessions at sub-millisecond latency. And then there was R — single-threaded, fragile, running bare Rscript as PID 1 with no supervision, no timeouts, and a health check that lied.

This is the story of how we tore it down and built Darkstar — a production-grade R analytics engine that runs OHDSI HADES analyses concurrently, recovers from crashes automatically, and executes 35% faster than the container it replaced.

In a single development session, we shipped three phases of a cognitive architecture that transforms Abby from a stateless RAG chatbot into a persistent, intelligent, context-aware research assistant. She now remembers who you are, routes complex questions to a more powerful brain, traverses clinical concept hierarchies, and warns you when your data has gaps. This post tells the complete story — the problems we solved, the architecture we built, and the engineering decisions behind 188 passing tests across 60+ new files.

Today we gave Parthenon's AI assistant a research library that most outcomes researchers would envy. Abby — our context-aware, privacy-preserving AI — now has 115,000+ SapBERT-embedded vectors spanning 2,258 peer-reviewed OHDSI papers, the complete Book of OHDSI, documentation from 30 HADES R packages, a decade of community forum Q&A, and 19 medical reference textbooks covering epidemiology, biostatistics, pharmacology, pathology, and clinical medicine.

This post tells the full story: why we built Abby, how the architecture works, what we harvested, what we learned about data quality in knowledge bases, and where we're headed next.

We ran every analysis type in Parthenon — estimation, prediction, SCCS, evidence synthesis, pathways, characterization, and incidence rates — against our full Acumenus CDM with 1 million synthetic patients. Thirteen seeded analyses. Seven different OHDSI methodologies. One session.

This post covers what happened when we moved from the 2,694-patient Eunomia demo dataset to production scale, the bugs that only surface at a million patients, and the hard-won lessons about propensity score modeling on synthetic data.