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Weekly Sync - 30 June 2026

Attendees

Benchmarking Results & Model Selection

Nirjas Binary Classifier Benchmarking

Completed comprehensive benchmarking of Nirjas comment classifier across five modeling families:

  • Lexical (TF-IDF): baseline approaches
  • Frozen embeddings (SentenceTransformer): pre-trained without fine-tuning
  • model2vec: static embedding distillation
  • model2vec-clf: model2vec with trainable classifier head
  • Fine-tuned encoders: end-to-end trained models (Ettin, ModernBERT, DistilBERT)

Decision: model2vec for Production

Selected: model2vec's trainable classifier on bge-distilled base (StaticModelForClassification)

Key Metrics:

  • F1 Score: 0.990
  • Balanced Accuracy: 0.9905
  • Model Size: 30 MB (fp32)
  • CPU Throughput: ~13,000 samples/second (8 threads, batch 64)
  • Short-form Recall: 1.00 (SPDX/one-line references)

Rationale:

  • Achieves Pareto-optimal performance for FOSSology's CPU-first scanning requirements
  • Exceptional throughput on commodity hardware with no GPU dependency at inference
  • Only 8M parameters enables deployment at scale
  • Within ~1 F1 point of best fine-tuned models while being 100–290× faster
  • Two-stage design (cheap filter → fine-tuned encoder on uncertain samples) can recover the accuracy gap if needed

Key Finding

Model choice is no longer the bottleneck—data quality is the critical path forward. Benchmarking validates the approach; improving labeled comment datasets will drive further gains.

Detailed Report: See nirjas-benchmark-report.md for full methodology, results table across all 15 models, and comprehensive analysis.

Action Items

  • Integrate model2vec-clf classifier into Nirjas extraction pipeline
  • Prepare deployment configuration for CPU-optimized inference
  • Plan data quality improvements for next iteration