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YOUR ASSEMBLY LEARNING PATH

A little more Assembly.
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 binary and hexadecimal notation, registers, signed arithmetic, and memory addresses. These x86-64 lessons are for learners with prior low-level programming experience.

Review a foundation whenever you need it: C values and computation

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

    Registers and operand widths

    Master

    Read conceptual x86-64 instruction traces in NASM-style Intel syntax.

    Start here, or skip ahead
    Open chapter: Registers and operand widths
  2. 02

    Sign extension and zero extension

    Master

    Preserve the intended interpretation when widening a narrow value.

    Open whenever you’re ready
    Open chapter: Sign extension and zero extension
  3. 03

    Addresses and sized memory operands

    Master

    Separate address calculation from reading a valid memory object.

    Open whenever you’re ready
    Open chapter: Addresses and sized memory operands
  4. 04

    Record layout, stride, and byte order

    Master

    Calculate field addresses from an explicitly stated layout.

    Open whenever you’re ready
    Open chapter: Record layout, stride, and byte order
  5. 05

    Arithmetic, masks, and shifts

    Master

    Compute with fixed-width bit patterns and make signedness assumptions explicit.

    Open whenever you’re ready
    Open chapter: Arithmetic, masks, and shifts
  6. 06

    Extracting and replacing packed bit fields

    Master

    Update one bit range while preserving neighboring fields.

    Open whenever you’re ready
    Open chapter: Extracting and replacing packed bit fields
  7. 07

    Carry, signed overflow, and wide addition

    Master

    Read flags according to the numeric contract.

    Open whenever you’re ready
    Open chapter: Carry, signed overflow, and wide addition
  8. 08

    Comparisons and signed branches

    Master

    Choose branch conditions that match the meaning of the compared values.

    Open whenever you’re ready
    Open chapter: Comparisons and signed branches
  9. 09

    Bounded loops over arrays

    Master

    Translate an explicit array contract into a correct machine-level loop.

    Open whenever you’re ready
    Open chapter: Bounded loops over arrays
  10. 10

    Bounded byte scans and sentinel searches

    Master

    Check valid extent before searching for a terminator.

    Open whenever you’re ready
    Open chapter: Bounded byte scans and sentinel searches
  11. 11

    Division and implicit register pairs

    Master

    Prepare the full dividend rather than only its low half.

    Open whenever you’re ready
    Open chapter: Division and implicit register pairs
  12. 12

    Leaf functions and calling contracts

    Master

    Write a small System V AMD64 leaf routine with explicit register responsibilities.

    Open whenever you’re ready
    Open chapter: Leaf functions and calling contracts
  13. 13

    Nested calls and System V stack discipline

    Master

    Preserve needed state across an arbitrary conforming callee.

    Open whenever you’re ready
    Open chapter: Nested calls and System V stack discipline

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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