Step 3: Inspect the Output Artifacts

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NEF File

The .nef file is a binary format. You can verify it was created and check its size:

ls -la build/MyStorage.nef

The NEF (Neo Executable Format) contains:

• Magic bytes (0x3346454E) -- identifies the file as a NEF
• Compiler metadata -- compiler name and version
• Method tokens -- references to native contract methods (when using --callt)
• Script -- the NeoVM bytecode
• Checksum -- SHA-256 hash for integrity verification

Manifest File

The .manifest.json file is human-readable. Inspect it with jq:

jq '.' build/MyStorage.manifest.json

Example output (abbreviated):

{
    "name": "MyStorage",
    "groups": [],
    "features": {},
    "supportedstandards": [],
    "abi": {
        "methods": [
            {
                "name": "set",
                "parameters": [{ "name": "newValue", "type": "Integer" }],
                "returntype": "Void",
                "offset": 0,
                "safe": false
            },
            {
                "name": "get",
                "parameters": [],
                "returntype": "Integer",
                "offset": 42,
                "safe": true
            },
            {
                "name": "increment",
                "parameters": [],
                "returntype": "Integer",
                "offset": 56,
                "safe": false
            }
        ],
        "events": [
            {
                "name": "ValueChanged",
                "parameters": [
                    { "name": "oldValue", "type": "Integer" },
                    { "name": "newValue", "type": "Integer" },
                    { "name": "setter", "type": "Hash160" }
                ]
            }
        ]
    },
    "permissions": [
        {
            "contract": "*",
            "methods": "*"
        }
    ],
    "trusts": [],
    "extra": null
}

Key fields to understand:

Field	Description
name	Contract name, derived from the Solidity contract name
abi.methods	Each public/external function becomes a method entry. safe: true means the method is read-only (view/pure).
abi.events	Each Solidity event becomes an event entry with typed parameters.
permissions	Declares which other contracts and methods this contract may call. Wildcards (*) mean unrestricted.
supportedstandards	Lists NEP standards the contract implements (e.g., ["NEP-17"]).

Inspect Specific Fields

Quick commands to extract common fields:

# Contract name
jq '.name' build/MyStorage.manifest.json

# Number of methods
jq '.abi.methods | length' build/MyStorage.manifest.json

# Method names
jq '[.abi.methods[].name]' build/MyStorage.manifest.json

# Event names
jq '[.abi.events[].name]' build/MyStorage.manifest.json

# Permissions
jq '.permissions' build/MyStorage.manifest.json

NeoVM Assembly (Optional)

To see the generated NeoVM opcodes:

./target/release/neo-solc MyStorage.sol -I devpack -O2 -f assembly -o build/MyStorage.asm
cat build/MyStorage.asm

This produces a human-readable disassembly showing each NeoVM instruction.