# Building Blocks

Building blocks (BBs) are software modules that can be deployed and combined in a standardized manner. Each building block is capable of working independently, but they can be combined to do much more. Read the [full definition in the GovStack Specifications](https://govstack.gitbook.io/specification/architecture-and-nonfunctional-requirements/introduction#2.3-building-blocks).

## What do we use to <mark style="background-color:blue;">build</mark> it?

The Building Block Software are build based on various different software stacks. Please visit the respective documentations for more insights.

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Building Block Software has been selected through a public tender procedure. Each software is one possible solution to fulfilling the Building Block Specifications. The selection is no recommendation.
{% endhint %}

For our Building Block Emulators, visit our [sub page on emulators](https://govstack.gitbook.io/sandbox/1.0.2-1/explore-stack/building-blocks/emulators).

## Where do we <mark style="background-color:blue;">demo</mark> it?

### Building Block Software in Use

| BB Software GitHub Repository                                                                                             | Used in...                                                                                                                                               |
| ------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- |
| MOSIP                                                                                                                     | [Unconditional Social Cash Transfer (USCT)](https://govstack.gitbook.io/sandbox/1.0.2-1/access-demos/usct-use-case)                                      |
| [X-Road](https://github.com/nortal/GovStack-IM-BB-X-Road)                                                                 | <p><a href="../access-demos/usct-use-case">Unconditional Social Cash Transfer (USCT)</a><br><a href="../follow-methodology/diy">USCT DIY Version</a></p> |
| Mifos Payment Hub                                                                                                         | [Unconditional Social Cash Transfer (USCT)](https://govstack.gitbook.io/sandbox/1.0.2-1/access-demos/usct-use-case)                                      |
| [OpenIMIS](https://github.com/GovStackWorkingGroup/sandbox-bb-digital-registries/tree/main/digital-registries/open-imis/) | [Unconditional Social Cash Transfer (USCT)](https://govstack.gitbook.io/sandbox/1.0.2-1/access-demos/usct-use-case)                                      |
| [Payment Emulator](https://github.com/GovStackWorkingGroup/sandbox-bb-payments/blob/main/emulator/docs/1-main.md)         | [USCT DIY Version](https://govstack.gitbook.io/sandbox/1.0.2-1/follow-methodology/diy)                                                                   |
| [Payment Adapter](https://github.com/GovStackWorkingGroup/sandbox-bb-payments/blob/main/adapter/docs/1-main.md)           | [USCT DIY Version](https://govstack.gitbook.io/sandbox/1.0.2-1/follow-methodology/diy)                                                                   |
| [iGrant.io](https://github.com/decentralised-dataexchange/bb-consent-docs/wiki)                                           | [Unconditional Social Cash Transfer (USCT)](https://govstack.gitbook.io/sandbox/1.0.2-1/access-demos/usct-use-case))                                     |

### Building Block Software in Progress

| BB Implementation      | BB Specification Compliance | Status  |
| ---------------------- | --------------------------- | ------- |
| Platform of Registries | Registry Specification 1.0  | Planned |

## Which <mark style="background-color:blue;">conceptual decisions</mark> do we follow?

The Building Block Implementations listed here have been openly procured by GovStack Initiative based on the GovStack Specifications. The providers of these BB implementations have been assigned to adapt/extend their offered software solutions to fully meet the GovStack Specifications for the respective Building Block.

## Further documentation