Context Variables

The runtime injects ctx and block metadata into contract execution.

ctx Properties

Property	Meaning
ctx.caller	immediate caller: an account or another contract
ctx.signer	original transaction signer; unchanged across a call chain
ctx.this	contract currently executing
ctx.owner	runtime __owner__ metadata, or None
ctx.entry	(contract, function) at the transaction entry point
ctx.submission_name	contract being deployed during module and constructor execution

If account alice calls contract_a, which then calls contract_b, the second call sees ctx.signer == "alice", ctx.caller == "contract_a", and ctx.this == "contract_b".

Use ctx.caller for immediate authorization. Use ctx.signer only when the original external signer is intentionally the authority.

For example, token allowance checks generally use ctx.caller, while direct user authorization may intentionally use ctx.signer.

Factory Deployment

Factories pass child source to the built-in submission contract. Validators compile the source and persist canonical IR; factories do not submit executable artifacts.

import submission

CHILD_SOURCE = """
value = Variable()

@construct
def seed(label: str):
    value.set(label)

@export
def read() -> str:
    return value.get()
"""

@export
def deploy_child(name: str, label: str):
    submission.submit_contract(
        name=name,
        code=CHILD_SOURCE,
        owner=ctx.caller,
        constructor_args={"label": label},
    )

During the child's module and constructor execution:

• ctx.this and ctx.submission_name are the child name
• ctx.caller is the factory contract
• ctx.signer is the original transaction signer
• ctx.entry remains the outer transaction entry point

Runtime Ownership

ctx.owner is separate from an application variable such as owner = Variable(). Transfer runtime ownership through the authorized submission surface:

import submission

@export
def handoff(contract: str, new_owner: str):
    submission.change_owner(contract=contract, new_owner=new_owner)

Block Metadata

Value	Meaning
now	finalized block timestamp
block_num	executing block height
block_hash	executing block hash
chain_id	network chain identifier

These values come from consensus context, not the validator's local clock.