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YOUR HASKELL LEARNING PATH

A little more Haskell.
A little more confidence.

One idea at a time, with examples you can follow and checkpoints to see what’s clicking. New here? Begin with chapter one. Know a little already? Jump right in.

Before you start

Assumes basic function and list experience. The course introduces Haskell expressions and type signatures, then develops pattern matching and immutable transformations.

Review a foundation whenever you need it: Small functions · Lists

Start chapter one Ready for the final?
13 open chapters. Your progress is saved as you go.

Your chapters

Choose any starting point
  1. 01

    Expressions, types, and application

    Intermediate

    Read Haskell functions as typed expressions rather than mutable procedures.

    Start here, or skip ahead
    Open chapter: Expressions, types, and application
  2. 02

    Higher-order functions and composition

    Intermediate

    Build transformations by connecting compatible function types.

    Open whenever you’re ready
    Open chapter: Higher-order functions and composition
  3. 03

    Patterns and guards

    Intermediate

    Describe alternatives with ordered equations and explicit conditions.

    Open whenever you’re ready
    Open chapter: Patterns and guards
  4. 04

    Algebraic data types and recursive models

    Intermediate

    Encode alternatives and their required data directly.

    Open whenever you’re ready
    Open chapter: Algebraic data types and recursive models
  5. 05

    Structural recursion and base cases

    Intermediate

    Follow recursive list processing with a clear measure of progress.

    Open whenever you’re ready
    Open chapter: Structural recursion and base cases
  6. 06

    List transformations and laziness

    Advanced

    Compose list operations and reason about how much input is demanded.

    Open whenever you’re ready
    Open chapter: List transformations and laziness
  7. 07

    Fold direction, demand, and strictness

    Advanced

    Choose evaluation behavior as well as a combining operation.

    Open whenever you’re ready
    Open chapter: Fold direction, demand, and strictness
  8. 08

    Maybe and total interfaces

    Advanced

    Represent an absent result without a partial list operation.

    Open whenever you’re ready
    Open chapter: Maybe and total interfaces
  9. 09

    Either and explanatory failures

    Intermediate

    Make failure information part of a total result type.

    Open whenever you’re ready
    Open chapter: Either and explanatory failures
  10. 10

    Traverse collections of checked results

    Advanced

    Turn many small validations into one structured outcome.

    Open whenever you’re ready
    Open chapter: Traverse collections of checked results
  11. 11

    Type classes, newtypes, and laws

    Advanced

    Express capabilities while preserving domain distinctions.

    Open whenever you’re ready
    Open chapter: Type classes, newtypes, and laws
  12. 12

    Persistent maps and explicit lookup failure

    Advanced

    Choose keyed structures with predictable update semantics.

    Open whenever you’re ready
    Open chapter: Persistent maps and explicit lookup failure
  13. 13

    Pure computation and IO sequencing

    Advanced

    Keep transformations pure and sequence external actions at the boundary.

    Open whenever you’re ready
    Open chapter: Pure computation and IO sequencing

PUT IT TOGETHER

Final assessment & certificate

30 multiple-choice questions and 2 written coding problems. Pass the knowledge section at 80% overall and at least 50% in every chapter area, complete and review the written practice, and meet the attempt-integrity checks to unlock your certificate.

The certificate records a CodeQuest foundations assessment. Written work is self-reviewed; identity and independent proficiency are not verified.

Open final assessment

Take an issuer-recorded assessment with a verifiable certificate

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