Declarative AI agent
environment manager.

カセット: cassette. plug in, swap out, share.

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~/dev/kasetto

❯kasetto

SIDE AGET STARTED · FEATURES · EXAMPLE

A1QUICKSTART

INSTALL

curl -fsSL kasetto.dev/install | sh

GITHUB119v3.6.2github.com/pivoshenko/kasetto ↗

DOCSkasetto.dev/docs ↗

A2FEATURES

DECLARATIVE

One YAML file: skills, commands, MCPs, and instructions. Apply globally or per project; compose with `extends`.

ENTERPRISE & PRIVATE REPOSITORIES

Pull from GitHub, GitLab, Bitbucket, or self-hosted repos, public or private. Secrets resolve from `kst_*` placeholders at sync time, so they're never committed or locked.

MULTI-AGENT

Write once, ship everywhere. Claude Code, Cursor, Codex, Copilot: one sync keeps every agent current.

SKILLS, COMMANDS, MCPS & INSTRUCTIONS

All four asset kinds from one source, transformed into each agent's native format and auto-merged. Share tools and prompts like a repo link.

SPEED

Built in Rust. Content is hashed and diffed against a lock file, so only what changed is touched. Syncs finish in seconds.

UNIVERSAL

One static binary for macOS, Linux, and Windows. JSON output and real exit codes. Same behavior on your laptop or in CI.

A3SECRET SOURCES

Environment

${kst_VERCEL_TOKEN}

credentials.yaml

${kst:crd:vercel/token}

1Password

${kst:op:Private/Vercel/token}

HashiCorp Vault

${kst:vault:secret/app#token}

KeePass

${kst:kp:Vercel/API#Password}

AWS Secrets Manager

${kst:aws:prod/db#password}

Google Secret Manager

${kst:gcp:db-password}

Azure Key Vault

${kst:az:my-vault/db}

pass / gopass

${kst:pass:work/vercel}

macOS Keychain

${kst:keychain:vercel-token}

A4EXAMPLE

kasetto.yaml

1# Option A: preset destination by agent (see README for supported agent values)

2agent:

3 - codex

4 - claude-code

6# Option B: manual destination (takes precedence if both are set)

7# destination: ./.agents/skills

9skills:

10 # "*" syncs every skill in the source. Each is a directory with a SKILL.md,

11 # discovered in the source root or its skills/ subdirectory

12 - source: github.com/vercel-labs/next-skills

13 # ref: v1.0.0 # pin to a tag or commit; omit to track the default branch

14 skills: "*"

16 # or list skills by name

17 - source: github.com/anthropics/skills

18 skills:

19 - doc-coauthoring

20 - frontend-design

21 - pptx

23 # sub-dir: resolve the named skills under this path, e.g. skills/productivity/grill-me/

24 - source: github.com/mattpocock/skills

25 sub-dir: skills/productivity

26 skills:

27 - grill-me

28 - caveman

30 # path: a skill in a non-standard location → <path>/<name>/, here skills/engineering/improve-codebase-architecture/

31 - source: github.com/mattpocock/skills

32 skills:

33 - name: improve-codebase-architecture

34 path: skills/engineering

36commands:

37 # names resolve to commands/<name>.md in the source (nested dirs namespace, e.g. git:commit)

38 - source: github.com/gsd-build/get-shit-done

39 commands:

40 - gsd: explore

41 - gsd: fast

43instructions:

44 # instructions wire CLAUDE.md / .cursor/rules / AGENTS.md etc. from instructions/<name>.{md,mdc}

45 # "*" syncs every instruction; aggregate files (CLAUDE.md, AGENTS.md) get managed blocks

46 - source: github.com/pivoshenko/pivoshenko.ai

47 instructions:

48 - docs-autoupdate

49 - multi-agent-dispatch

51mcps:

52 # names resolve to mcps/<name>.json in the source

53 - source: github.com/pivoshenko/pivoshenko.ai

54 branch: main # track a specific branch (use ref: to pin a tag or commit)

55 mcps:

56 - github

57 - vercel

58 - kaggle

SIDE BAGENTS · INSTALL

B1SUPPORTED AGENTS

22 PRESETS, BUILT IN

CLAUDE CODE

CURSOR

CODEX

ANTIGRAVITY

B2INSTALL

MACOS / LINUX

curl -fsSL kasetto.dev/install | sh

WINDOWS (POWERSHELL)

powershell -ExecutionPolicy Bypass -c "irm kasetto.dev/install.ps1 | iex"

HOMEBREW

brew tap pivoshenko/tap
brew trust pivoshenko/tap
brew install kasetto

CARGO

cargo install kasetto

Declarative AI agent environment manager.

Declarative AI agent
environment manager.