midnightntwrk/midnight-expert/basic-start

EPHEMERAL — Everything produced by this skill is disposable. This walkthrough generates code solely to verify your environment works and to build familiarity with Midnight development. Do not commit, push, or retain any generated code. Delete the working directory when done.

Basic Start: Your First Midnight DApp

A step-by-step procedural guide that takes you from zero to a working Midnight DApp on a local devnet. Each step builds on the previous one, verifying your environment works correctly along the way.

Prerequisites

Before starting, ensure:

• Docker is running (docker info should succeed)
• Node.js 22+ is installed (node --version)
• Compact CLI is installed (compact --version) — if not, use /midnight-tooling:install-cli

Run /midnight-tooling:doctor to check all prerequisites at once.

Working Directory

Create a temporary directory for this walkthrough. All generated files go here.

mkdir -p /tmp/midnight-basic-start && cd /tmp/midnight-basic-start

Steps

Work through each step in order. Each step's reference file contains the full procedure.

When something errors

Your first stop for any error code or message is `/midnight-status-codes:lookup`. It decodes node rejections (e.g. 1010: Custom error: 117), SDK/Effect errors, Compact compiler diagnostics, proof-server and indexer errors, and more — telling you what produced the error and how to fix it.

/midnight-status-codes:lookup 117      # a numeric node/ledger code
/midnight-status-codes:lookup NotNormalized   # an error name

Common early ones on a fresh devnet: 117 (NotNormalized — set a small additionalFeeOverhead, see step 4/5) and 1010 (the Substrate envelope that wraps the real Custom(N) cause). For environment problems, run /midnight-tooling:doctor.

When You're Done

Delete the temporary working directory:

rm -rf /tmp/midnight-basic-start

Stop the devnet if you no longer need it:

/midnight-tooling:devnet stop --remove-volumes