Back to library

🧪Use Eval Frameworks: Ragas, DeepEval, TruLens

Stop hunting for a single 'best' RAG eval tool. You'll learn the four core RAG metrics, score the same app in Ragas and DeepEval, see where each framework wins, and ship a layered eval stack you can defend to your team.

Advanced14 drops~2-week path · 5–8 min/daytechnology

Phase 1The four RAG metrics every framework frames around

Learn the four RAG metrics every eval frames around

4 drops

  1. RAG evals split into retrieval and generation — and both can fail silently

    6 min

    RAG evals split into retrieval and generation — and both can fail silently

  2. Faithfulness catches hallucinations the chunks could have prevented

    6 min

    Faithfulness catches hallucinations the chunks could have prevented

  3. Answer relevancy catches the answer that's right about the wrong question

    6 min

    Answer relevancy catches the answer that's right about the wrong question

  4. Context precision and recall measure your retriever, not your LLM

    7 min

    Context precision and recall measure your retriever, not your LLM

Phase 2Score the same RAG app in Ragas and DeepEval

Score the same RAG app in Ragas and DeepEval

5 drops

  1. Build a 20-row eval set with question, contexts, answer, and ground truth

    7 min

    Build a 20-row eval set with question, contexts, answer, and ground truth

  2. Run Ragas — the framework built around the four-metric vocabulary

    8 min

    Run Ragas — the framework built around the four-metric vocabulary

  3. Run DeepEval — the framework that thinks like pytest

    8 min

    Run DeepEval — the framework that thinks like pytest

  4. Diff the Ragas and DeepEval reports — and explain the disagreements

    8 min

    Diff the Ragas and DeepEval reports — and explain the disagreements

  5. Run TruLens — the framework that scores app traces, not test cases

    8 min

    Run TruLens — the framework that scores app traces, not test cases

Phase 3When you outgrow Ragas: CI, custom metrics, tracing

CI integration, custom metrics, and end-to-end tracing

4 drops

  1. CI is too slow and too expensive — every PR runs 200 LLM calls

    7 min

    CI is too slow and too expensive — every PR runs 200 LLM calls

  2. Your domain breaks the default faithfulness prompt — write a custom metric

    7 min

    Your domain breaks the default faithfulness prompt — write a custom metric

  3. You need to debug a multi-step chain — Ragas can't see your retriever

    7 min

    You need to debug a multi-step chain — Ragas can't see your retriever

  4. Your team standardized on Ragas — when is it worth layering a second framework?

    7 min

    Your team standardized on Ragas — when is it worth layering a second framework?

Phase 4Pick a stack for a hypothetical RAG — and defend the picks

Pick a stack for your RAG and defend the picks

1 drop

  1. Pick the eval stack for a real (or hypothetical) RAG and write the defense

    10 min

    Pick the eval stack for a real (or hypothetical) RAG and write the defense

Frequently asked questions

What's the difference between Ragas, DeepEval, and TruLens?
This is covered in the “Use Eval Frameworks: Ragas, DeepEval, TruLens” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
Can I use Ragas and DeepEval together, or do I have to pick one?
This is covered in the “Use Eval Frameworks: Ragas, DeepEval, TruLens” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
How do faithfulness and answer relevancy actually differ?
This is covered in the “Use Eval Frameworks: Ragas, DeepEval, TruLens” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
When does TruLens earn its keep over Ragas or DeepEval?
This is covered in the “Use Eval Frameworks: Ragas, DeepEval, TruLens” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
How do I run RAG evals in CI without burning a fortune on judge tokens?
This is covered in the “Use Eval Frameworks: Ragas, DeepEval, TruLens” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.

Related paths

🐍Python Decorators Introduction

Build one mental model for Python decorators that covers closures, argument passing, functools.wraps, and stacking — then ship a working caching or logging decorator from scratch in under 30 lines.

Applied~2-week path · 5-8 min/day

🦀Rust Lifetimes Explained

Stop reading `'a` as line noise and start reading it as scope arithmetic — one failing snippet at a time — until you can thread lifetimes through a small parser or iterator adapter without fighting the borrow checker.

Applied~2-week path · 5-8 min/day

☸️Kubernetes Core Concepts

Stop drowning in 30+ resource types. Build the mental model one primitive at a time -- pods, deployments, services, ingress, config -- then deploy a real app with rolling updates and health checks.

Applied~2-week path · 5-8 min/day

📈Big O Intuition

Stop treating Big O as math you memorized for an interview — build the intuition to spot O(n²) disasters, pick the right data structure without thinking, and rewrite a slow function from O(n²) to O(n) in under five minutes.

Foundations~2-week path · 5-8 min/day