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SFT (Supervised Fine-Tuning)

What is Fine-Tuning?

Supervised Fine-Tuning (SFT) is the process of training an existing pre-trained model on your specific data to adapt it to your domain or task. It adjusts the model's parameters to specialize in your use case.

The Core Idea: Take a general-purpose LLM → Train it on your data → Get a specialized model

Why Fine-Tuning:

  • Improve performance on domain-specific tasks
  • Learn specialized terminology and patterns
  • Reduce prompt engineering needs
  • Better consistency in outputs

Frontend Engineer Recommendation

For Implementation: Hire ML Engineers

As a frontend developer, you generally should not be implementing SFT yourself unless using a managed service like OpenAI's fine-tuning API. This is typically the domain of Machine Learning Engineers.

SFT vs RAG vs Prompt Engineering

AspectPrompt EngineeringRAGFine-Tuning (SFT)
CostVery Low (free)Low (inference + retrieval)Very High (GPU training)
Setup TimeMinutesHours to daysDays to weeks
Data NeededNone (just prompts)Documents for retrieval100s-1000s labeled examples
SpeedFastMedium (retrieval overhead)Fast (after training)
UpdatesInstantInstant (update knowledge base)Requires retraining
Best ForGeneral tasksDynamic knowledgeSpecialized domains

When to Use Fine-Tuning

✅ Good Use Cases

  1. Specialized Domain Language

    • Medical diagnosis (medical terminology)
    • Legal document analysis (legal jargon)
  2. Consistent Output Format

    • Always need specific JSON structure
    • Code generation in proprietary framework
  3. Style and Tone

    • Brand-specific writing style
    • consistent personality across responses
  4. Performance Optimization

    • Need smaller model with specialized capability to reduce costs/latency

❌ Bad Use Cases (Use RAG Instead)

  1. Frequently Changing Information

    • Product catalogs
    • News and updates
  2. Large Knowledge Bases

    • Company wikis
    • Technical manuals
  3. Limited Budget

    • Startups without GPU access
    • Prototype/MVP stage

Services for Fine-Tuning

If you decide SFT is necessary, these platforms offer managed fine-tuning services that don't require managing GPU infrastructure:

Next Steps

  • Evaluate if you really need SFT (try RAG first)
  • Start with OpenAI's fine-tuning API if you must proceed
  • Collaborate with ML Engineers for complex model training