This repository is used to generate stage solutions and hints for CodeCrafters challenges.

🚀 Usage

Install dependencies

bun install

Fetch challenges

StageGen does not currently fetch challenges. You need to place your challenge files under challenges/<slug>.

What you need for each challenge:

• stage_descriptions/
• compiled_starters/
• solutions/

Nothing else is required. Do not copy the challenge’s .git folder.

For example, to copy the build-your-own-redis challenge (assuming you have the local repo):

# from your StageGen repo root
mkdir -p challenges/build-your-own-redis

# copy only the three folders from your source challenge repo
cp -R /path/to/source/build-your-own-redis/stage_descriptions challenges/build-your-own-redis/
cp -R /path/to/source/build-your-own-redis/compiled_starters challenges/build-your-own-redis/
cp -R /path/to/source/build-your-own-redis/solutions challenges/build-your-own-redis/

# make sure you did not bring over a .git folder
rm -rf challenges/build-your-own-redis/.git

Environment variables

• OPENAI_API_KEY required
• DRY_RUN=1 to skip writing files

Run locally

Generate for all languages found under solutions/*:

bun run src/index.ts \
  --challenge-slug build-your-own-redis \
  --stage-id 02-rg2

Target a specific set of languages:

bun run src/index.ts \
  --project-root . \
  --challenge-slug build-your-own-redis \
  --stage-id 02-rg2 \
  --targets javascript,python,go

Dry run without writing files:

DRY_RUN=1 bun run src/index.ts \
  --project-root . \
  --challenge-slug build-your-own-redis \
  --stage-id 02-rg2

💻 CLI reference

--project-root <path>            default: cwd
--challenge-slug <slug>          if omitted, derived from folder name
--stage-id <id>                  example: 02-rg2
--stage-kind <base|localized>    default: base
--targets <csv>                  example: javascript,go,python
--refs <csv>                     default: python,rust,go
--model <name>                   default: gpt-5
--lang-concurrency <n>           default: 4
--task-concurrency <n>           default: 2