CLI Reference

Mero DevTools ships two independent CLIs. calimero-abi-codegen (from @calimero-network/abi-codegen) generates a typed client from an ABI manifest; create-mero-app scaffolds a new project from the KV Store reference app.

calimero-abi-codegen

Parses a WASM-ABI v1 manifest and generates a fully-typed TypeScript client. It runs in one of two modes: code generation (the default) or validation (--validate).

# Install
npm install @calimero-network/abi-codegen

# …or run without installing
npx @calimero-network/abi-codegen -i abi.json -o src/generated

Options

Flag	Description	Default
-i, --input <file>	Input ABI JSON file.	abi.json
-o, --output <dir>	Output directory for the generated file (created if missing).	src
--client-name <Name>	Explicit client class name; sanitized to a valid identifier.	derived (see below)
--name-from <path>	Derive the client name from a file path (e.g. the .wasm file).	—
--import-path <path>	Import path for the runtime dependency in generated code.	@calimero-network/mero-react
--validate	Validate the manifest only; generate nothing. Exits 0 on success.	—
-h, --help	Print usage help.	—

Note

The generator writes exactly one file, <ClientName>.ts, into the output directory. Type definitions and the client class live in that single file.

Client name resolution

When code-generating, the client class name is resolved in strict priority order:

1. --client-name <Name> — highest priority. Passed through sanitizeClassName: split on non-alphanumeric characters, capitalize the first letter of each part, keep the rest. "Task Board" → TaskBoard, "kv-store" → KvStore, an already-valid TestClient stays TestClient.
2. --name-from <path> — derived with deriveClientNameFromPath: take the file basename, strip its extension, split on non-alphanumerics, and append Client. Segments of one or two characters are upper-cased whole.
3. Input basename — falls back to deriving from the -i file name with the same deriveClientNameFromPath rule.

--name-from and --client-name capitalize differently

The two paths use different functions, so short segments diverge:

--name-from kv_store.wasm     # → KVStoreClient   (kv → KV)
--client-name kv-store        # → KvStore         (kv → Kv)
--name-from abi-conformance.json  # → AbiConformanceClient
--name-from plantr.wasm           # → PlantrClient

--name-from upper-cases one- and two-character segments (kv → KV), which is why kv_store.wasm becomes KVStoreClient, not KvStoreClient.

Examples

Generate

# Generate into src/generated/ (name derived from abi.json → AbiClient)
calimero-abi-codegen -i abi.json -o src/generated

# Explicit client class name
calimero-abi-codegen -i abi.json -o src/generated --client-name TodoClient

# Derive the name from the WASM binary path
calimero-abi-codegen -i abi.json -o src/generated --name-from kv_store.wasm

Validate only

calimero-abi-codegen --validate -i abi.json

✅ ABI manifest validated successfully!
📊 Summary:
   Methods: 5
   Events: 2
   Types: 8

Custom import path

# Point generated imports at a different runtime package
calimero-abi-codegen -i abi.json -o src/generated \
  --import-path @calimero-network/mero-js

package.json script

{
  "scripts": {
    "codegen": "calimero-abi-codegen -i abi.json -o src/generated",
    "build": "npm run codegen && vite build"
  }
}

On a successful generation the tool prints a summary and the path it wrote:

✅ Code generation completed successfully!
📊 Summary:
   Methods: 5
   Events: 2
   Types: 8
   Client: TodoClient
📁 Generated files:
   /abs/path/src/generated/TodoClient.ts

If the input file does not exist, or the manifest fails validation, the tool prints an error and exits with a non-zero status without writing anything.

create-mero-app

Scaffolds a new Calimero application from the KV Store reference app in the calimero-network/apps monorepo.

npx create-mero-app my-app

# …or the npm-init form
npm create mero-app my-app

Usage

create-mero-app [project-name] [options]

Argument / flag	Description
[project-name]	Directory to scaffold into. Omit to use the current directory; its basename must be a valid npm package name.
-t, --template <name>	Template to use. rust is the only one, and the default, so this flag is optional.

Templates

Name	Source	Contents
rust	calimero-network/apps → apps/kv-store	Rust WASM contract + React frontend

The template is a directory inside the apps monorepo, not a repository of its own. The standalone calimero-network/kv-store and calimero-network/kv-store-js repos this CLI used to clone were archived when every app moved into that monorepo.

There is no javascript template. kv-store-js was archived with no replacement — for a JavaScript contract, see the examples in calimero-sdk-js.

What it does

1. Validates the project name as an npm package name; refuses a non-empty existing directory.
2. Sparse-checks-out apps/kv-store from calimero-network/apps into a temp directory. Cone mode also brings the repo-root files, which the next step needs.
3. Copies the app into your project, excluding .git, .github, .gitignore, .gitattributes, .gitmodules, and node_modules.
4. Detaches it from the monorepo — see below.
5. Writes a project root (package.json, pnpm-workspace.yaml) and a README describing the standalone commands.
6. Prints next steps: cd, pnpm install, pnpm logic:build, pnpm dev.

Detaching from the monorepo

An app in apps is deliberately not self-contained: shared versions live at the repo root so one edit moves the whole fleet. Copying the directory alone would produce a project that cannot install and cannot build, so three kinds of inherited reference are resolved against the checkout it came from:

Inherited	Resolved from	Becomes
"react": "catalog:"	pnpm-workspace.yaml	the concrete version range
edition.workspace = true	root Cargo.toml	the concrete value
calimero-sdk.workspace = true	root Cargo.toml	the pinned git dependency
extends: ../../../tsconfig.base.json	root tsconfig.base.json	the file, hoisted into the project

Nothing is hardcoded in the CLI: the values come from the commit that was cloned, so a core bump or a frontend release in apps reaches newly scaffolded projects with no change here. The crate also gains its own [workspace] table, without which cargo would search parent directories and either fail or adopt an unrelated workspace above your project.

A scaffolded project does not track the template

Versions are pinned at scaffold time. The project upgrades on its own schedule from then on — it is a starting point, not a live link to apps.

Caution

create-mero-app does not initialise a git repository — the scaffolded project has no .git. Run git init yourself if you want version control.