Workers

A worker implements atomic functionalities that will not be broken further by the controller. Tierkreis workers come in three flavors:

• Builtin workers, provided by Tierkreis itself

• User defined workers, by using the @worker.task() decorator or writing external ones

• Prepackaged workers from the Tierkreis developers

Important

External workers are a way to interface non-python programs with Tierkreis. As long as there is a runnable binary, you can provide a thin wrapper which allows Tierkreis to run this program.

• Complex types in Tierkreis Python workers
  • JSON style types
  • Struct using NamedTuple
  • bytes
  • DictConvertible and ListConvertible
  • Pydantic BaseModels
  • Special Python types
• Custom serializers
• External Workers
  • IDL
  • Parsing Inputs and Outputs
• Hello world worker
  • Worker code
  • Generating stubs
  • Graph creation
  • Execution
• Prepackaged workers
  • Qiskit Aer worker
  • IBMQ Worker
  • Nexus worker
  • Pytket worker
  • Quantinuum Backend Worker
  • Qulacs worker

Generating workers from the cli

The cli supports you in setting up new workers. You can declare a worker by running:

tkr init worker --worker-name <worker-name>

This will generate a new worker directory and the associated files. Each worker is an independent project, with it’s own dependencies. The main.py file is the entrypoint for the worker. Here you can decorate a python function with @worker.task() to declare a worker task. At runtime, main.py will be called by an executor (more on that later) and search for the correct task in it. The inputs and outputs are preserved with the storage layer and be tracked by Tierkreis. Other side-effects (e.g., writing a separate file) won’t be checked.

When writing a workflow you don’t need to call this function directly. Instead you need to provide the so-called function stubs to the task definition, which are available as the workers api. You can generate the stubs from the cli:

tkr init stubs

or running

uv run <worker_dir>/main.py --stubs-path <path to stubs>.py

This allows you to include a workers api for typechecking purposes without the need to building them and therefore making your development environment less polluted.

Prepackaged workers

The following outlines the functionality of the prepackaged workers. Currently the following workers are provided as separate packages on pypi:

• IBMQ

• Qiskit Aer

• Pytket

• Quantinuum Nexus

• Quantinuum Backend

Qiskit Aer

Compile and run quantum circuits locally with Qiskit Aer. More detailed docs here.

IBMQ

Compile and run quantum circuits locally with IBMQ. More detailed docs here.

Pytket

The pytket compiler suite to optimize circuits. The worker only contains a subset of common operations. For a custom compilation pipeline it is advised to build your own worker.

More detailed docs here.

Installation

pip install tkr-pytket-worker

will install an executable Python script tkr_pytket_worker into your virtual environment.

Example

See the example hamiltonian_graph.py.

Quantinuum Nexus

Interface to the Quantinuum Nexus platform. More detailed docs here.

Quantinuum Backend

Compile and run quantum circuits locally with Quantinuum backends. More detailed docs here.

Qulacs

Compile and run quantum circuits locally with Qulacs. More detailed docs here.