Can't build_transactions / simulate without signatures / signors

[jzuhusky]

Cannot create unsigned transactions using similate or build_transactions.

It's entirely possible I'm just a n00b but from all that I've read this should work.

Trying to do something like

group = (
        algorand
        .new_group()
        .add_payment(
            PaymentParams(
                sender=some_sender_acct, # not the 
               .....
            )
        )
        .add_app_call_method_call(
            AppCallMethodCallParams(
               .....
            )
        )
    )
    built = group.simulate(skip_signatures=True)

But group.simulate call raises a value error

ValueError: No signer found for address XOT....4RYP

I'm trying to build a series of unsigned transactions, serialize them, and then sign them in my Pera-wallet. I don't have the PKs to my wallet running on this server, but rather I just want the unsigned transactions to be created here and sent back to my wallet for signing.

Your environment

Running with test net algorand client.

from algokit_utils import AlgorandClient
algorand = AlgorandClient.testnet()

algokit doctor
You are using AlgoKit version 2.7.1, however version 2.9.0 is available. Please update using the tool used to install AlgoKit.
HTTP Request: GET https://api.github.com/repos/algorandfoundation/algokit-cli/releases/latest "HTTP/1.1 200 OK"
timestamp: 2025-09-08T00:45:48+00:00
AlgoKit: 2.7.1 (latest: 2.9.0)
AlgoKit Python: 3.12.11 (main, Jun 21 2025, 14:53:27) [Clang 17.0.0 (clang-1700.0.13.3)] (location: /Users/jzuhusky/.pyenv/versions/3.12.11)
OS: macOS-15.6.1-arm64-arm-64bit
docker: 28.2.2
docker compose: 2.36.2-desktop.1
git: 2.39.5
python: 3.12.11 (location: /Users/jzuhusky/.pyenv/versions/3.12.11/bin/python)
python3: 3.12.11 (location: /Users/jzuhusky/.pyenv/versions/3.12.11/bin/python3)
pipx: 1.7.1
poetry: 2.1.3
node: 24.2.0
npm: 11.3.0
brew: 4.5.7

If you are experiencing a problem with AlgoKit, feel free to submit an issue via:
https://github.com/algorandfoundation/algokit-cli/issues/new
Please include this output, if you want to populate this message in your clipboard, run `algokit doctor -c`

Steps to reproduce

1. Build a group of transactions like above

Expected behaviour

1. Simulate the transactions without a ValueError being raised / return a group of unsigned txns.

Actual behaviour

Value Error

[neilcampbell]

Thanks for reporting this @jzuhusky
This should definitely work, will get that fixed.

[neilcampbell]

A fix PR has been created, however an alternative approach is to use an empty signer, which would allow you to use build().
It should look something like below:

import algosdk.atomic_transaction_composer

group = (
        algorand
        .new_group()
        .add_payment(
            PaymentParams(
                signer=algosdk.atomic_transaction_composer.EmptySigner(),
                sender=some_sender_acct, # not the 
               .....
            )
        )
        .add_app_call_method_call(
            AppCallMethodCallParams(
               signer=algosdk.atomic_transaction_composer.EmptySigner(),
               .....
            )
        )
    )
    built = group.build()

[neilcampbell]

Fixed in 4.2.1