Getting started

Prerequisites

byox uses mise to pin the toolchain (Go 1.25) and just, so you don’t need Go installed globally.

brew install mise        # macOS; see mise docs for other platforms

Set up

git clone https://github.com/madhank93/build-your-own-x
cd build-your-own-x
mise install              # provisions Go 1.25 + just
just setup                # clones course + tester repos, builds testers, seeds Go starters

Daily loop

just tui                  # single-screen TUI: stage list left, instructions right

Rustlings-style watch mode is always on: save any file in solutions/<course>/ and the current stage’s tests run automatically, streaming into the right pane.

Or headless:

just test redis           # run official tests for redis's current stage (+ all prior as regression)
just status                # progress across courses

Your code lives in solutions/<course>/app/ — edit main.go, run tests, pass, next stage unlocks. progress.json records completion. Passing reruns every earlier stage too, exactly like the real platform.

How it works

• just setup shallow-clones codecrafters-io/build-your-own-<course> (course definition + stage instructions + Go starter) and codecrafters-io/<course>-tester (official tester), then builds each tester to testers/<name>/dist/main.out.
• byox invokes the tester with CODECRAFTERS_REPOSITORY_DIR=solutions/<course> and CODECRAFTERS_TEST_CASES_JSON covering stages 1..current; exit 0 marks the stage complete.
• Stage instructions render in the TUI from the vendored stage_descriptions/*.md.

TUI keys

Key	Action
↑/↓ j/k, g/G	move / top / bottom (moves across all courses)
enter (on a course header)	fold / unfold that course
esc esc	fold / unfold the cursor’s course from anywhere
t	run tests for the cursor’s course (or just save a file)
e	open the solution’s main.go in $VISUAL/$EDITOR; tests rerun on return
s	show / hide the reference solution for the selected stage
/	fuzzy-filter stages by name or slug, across all courses
c	jump to the current stage of the cursor’s course
J/K / pgup/pgdn	scroll the instructions / log / solution pane
esc	log or solution → instructions, or clear filter
q	quit

Reference solutions

Pressing s in the TUI shows a reference solution for the selected stage. This repo ships complete, tester-verified Go solutions for most stages, authored under reference-solutions/. Each reference-solutions/<course>/NN-slug/main.go was verified by running the official CodeCrafters tester cumulatively (stages 1..N) against it before being snapshotted. byox reads these first, falling back to CodeCrafters’ vendored free-stage solutions.

Browse every stage of every course — filter by course, search, and read the worked solution — in the Catalog.

Other commands

just build                       # build the engine binary
just reset <course> <stage>      # rewind a course's progress pointer to a stage (code untouched)

Next: browse the Catalog to see every course and stage.