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Let's Data Science course library

Courses that make difficult ideas click.

Watch the concept move, run the work yourself, and check what you understood before going on. Start from zero or follow a complete course track.

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Inside the library8h 30m

Production LLM Systems

Course tracks

Choose your route through the library.

Each route is made only from LDS courses. It is a recommended study order, separate from the broader career guides.

Full course library

Everything we teach, in one place.

Browse all 17 published courses. Every Pro course opens with a free first module.

17 courses

Access

01

SQL

Write the query. Then understand why it works.

3 courses

SQLFreeSQL FundamentalsQuery, filter, aggregate, and combine tables with JOINs.~10 hours4 modulesBeginnerView courseSQLProSQL Window FunctionsOVER(), ranking, LAG/LEAD, frame clauses, and fast analytical SQL.~11 hours8 modulesIntermediate to AdvancedView courseSQLFreeSQL MasteryHow joins, window functions, and complex queries work under the hood.~10 hours4 modulesIntermediate to AdvancedView course

02

Python & Data

Turn raw data into clear, repeatable analysis.

2 courses

Python & DataFreePython FundamentalsPython essentials for data science, run live in your browser.~13 hours6 modulesBeginner to IntermediateView coursePython & DataFreePandas FundamentalsDataFrames, selection, groupby, merging, reshaping, and time series.~8 hours7 modulesBeginner to IntermediateView course

03

Statistics & Experiments

Make uncertainty visible before making a decision.

3 courses

Statistics & ExperimentsFreeStatistics FoundationsMean, median, mode, and spread, built as visual intuition.~4 hours4 modulesBeginnerView courseStatistics & ExperimentsProProbability for Data ScientistsFrom coin flips to the math that powers every ML model.~9 hours8 modulesBeginner to IntermediateView courseStatistics & ExperimentsProA/B Testing & ExperimentationExperiments that hold up, plus CUPED, sequential testing, and bandits.~8 hours8 modulesBeginner to AdvancedView course

04

Machine Learning

Train models without fooling yourself.

1 course

Machine LearningProMachine Learning Fundamentals (scikit-learn)The supervised-learning loop, trained live on the Lendly dataset.~9 hours8 modulesIntermediateView course

05

AI Engineering

Build the model intuition, application layer, and production discipline.

8 courses

AI EngineeringFreeLLM FoundationsFrom BPE tokens through attention, scaling laws, and interpretability.~8 hours8 modulesBeginner to AdvancedView courseAI EngineeringFreeBuild a Tiny LLM: From Tokens to TextBuild a working GPT from scratch and watch it write, token by token.6h 45m8 modulesBeginner to AdvancedView courseAI EngineeringProBuilding RAG Systems & Vector SearchBM25 to dense to hybrid to rerank, every step measured on one corpus.~9 hours8 modulesIntermediate to AdvancedView courseAI EngineeringProBuilding AI AgentsThe agent loop, tools, planning, and memory, with real machinery and a deterministic model.~9 hours8 modulesIntermediate to AdvancedView courseAI EngineeringProAI Evals: Test, Measure & Ship LLM AppsScorers, judge alignment, and a CI gate that catches regressions.~9 hours8 modulesIntermediate to AdvancedView courseAI EngineeringProFine-Tuning LLMs: Make the Model YoursSFT, LoRA, DPO, and distillation on a real 1.09M-parameter model.~7 hours8 modulesIntermediate to AdvancedView courseAI EngineeringProContext Engineering & AI WorkflowsOne workflow from naive prompt to measured system, with gates.5h 55m7 modulesBeginner to AdvancedView courseAI EngineeringProProduction LLM SystemsTurn one working LLM call into a service people can depend on.8h 30m8 modulesIntermediate to AdvancedView course