Workflow automation and validation

Turning a pipeline transition into a dependable laboratory system

Formal validation, dependency-aware orchestration, result aggregation, and downstream chaining for public-health genomics.

$ case-study –system workflow-operations

Role
Led and implemented the influenza pipeline transition; contributor to shared pathogen-genomics workflows.

Stack
Python, Nextflow, Quarto, SQLAlchemy, SQLite, ART read simulation, SLURM, Apptainer, structured JSON logging.

Status
Production workflow, automation, validation, and result-management tooling.

The problem

Replacing a pipeline executable is only a small part of changing a laboratory workflow. The new analysis must be validated against predefined criteria, installed reproducibly, run without constant manual intervention, connected to downstream systems, and translated into data structures that scientists can review and report.

The operational system

flowchart LR
  A[Sequencing run] --> B[Input QC gates]
  B --> C[Versioned nf-flu workflow]
  C --> D[Pluggable result parsers]
  D --> E[(Results database)]
  D --> F[Reports and notifications]
  C --> G[Downstream mutation analysis]
  H[Clinical and simulated truth sets] --> I[Formal validation]
  C --> I
  I --> J[Root-cause findings and fixes]
Figure 1: From sequencing input to validated, reportable results.

The automation layer describes pipeline order and dependencies as configuration, including the version of each pipeline and its compatible Nextflow release. It applies configurable QC gates, supports backlog processing, records structured events, and chains successful output into downstream mutation analysis.

Result collection uses a registry of small parsers for subtyping, clade calls, mapping statistics, completeness, HPAI motifs, genotyping, provenance, and mixture reports. New result types can be added without changing orchestration.

Formal validation

Six evaluation axes were defined before analysis: subtype concordance, clade concordance, genome completeness, consensus accuracy, reproducibility, and computational performance.

  • Subtype validation reported 100% accuracy in a 150-isolate clinical cohort and a 200-isolate simulated cohort.
  • Clade validation reported 100% accuracy in the stated clinical cohort.
  • Consensus accuracy was evaluated across 1,184 influenza segment sequences.
  • Samples were stratified across viral-load ranges rather than selected only from easy, high-input cases.

Validation also found a defective reference associated with a consistent loss of terminal completeness in affected H5N1 samples. Removing it raised completeness from roughly 97% to above 99.7%, converting a metric anomaly into a concrete upstream data fix.

Shared public work

My role in these projects includes workflow development, automation, validation, provenance, and operational improvements. They are shared organizational codebases, not solely authored repositories.

Broader pattern

The reusable idea is that production bioinformatics is a system, not a single workflow file. A dependable implementation combines scientific acceptance criteria, reproducible execution, explicit dependency and version management, structured operational state, durable results, and documentation for both developers and laboratory users.