SWAPI - Open source complementary currency toolkit

Build Status Clojars Project Freecoin project stats License: AGPL v3

The social wallet toolkit is a set of tools to let groups design and/or manage currencies in a simple and secure way.
It is made for participatory and democratic organisations who want to incentivise participation -- unlike centralised banking databases and experiment with different economic models -- unlike centralised nation state.

πŸ‘€ With SWAPI you can

  • βœ… Create your currency from scratch and use it within your group
  • βœ… Implement different economic governances
  • βœ… Aggregate and visualize data generated during time
  • βœ… Use your currency offline (eg. during festivals) via printed qrcode
  • βœ… Add tags to your transactions to filter them
  • βœ… Add a message to your transactions
  • βœ… Use it as wallet for cryptocurrencies
  • βœ… Use it with a default authentication system or use it within an existing userbase

πŸ”§ Technical overview

The Social Wallet API allows both to create currencies from scratch and to facilitate the integration of blockchain functions into existing front-end applications, providing an easy backend of documented REST API endpoints that are validated and, in case of error, reporting meaningful messages.
It also gives the opportunity to add metadata to transactions which can be very useful for grouping, labeling and filtering as well as adding some context.

The social wallet API layer is agnostic from any specific database implementation, being able to connect with different ledgers based on ad-hoc connectors.
At present, available ledgers connectors are for mongodb and nippy (a filesystem storage) as well as for bitcoin blockchain and any blockchain node compatible with bitcoin core and that supports generic bitcoin RPC calls.

The Social wallet API can also operate with only the DB without any blockchain connection, which is great for experimentation, testing or situations where the complexity of a distributed ledger is not required.

🧰 The toolkit

The social wallet is built to be highly modular, and agnostic from any specific implementation - trying to suit a broader range of scenarios and giving freedom of experimentation to groups.
To do that, we created a suite of open source libraries that can be plugged together and customized upon necessities:

  • Freecoin core library: An interface to transactions operation
  • API: A clean and reliable API layer
  • Web app: A javascript-free client interface
  • Just-auth: Authentication and 2fa without frissle
  • Clj-storage: A minimalist clojure protocol abstraction over document databases

πŸš€ Getting Started

The Social Wallet API is written in Clojure and is fully cross-platform: one can run it locally on a GNU/Linux machine, as well on Apple/OSX and MS/Windows.


Please install:

  1. A JDK. The software is tested on openJDK versions 7 and 8 as well as with oracleJDK 8 and 10. Make sure that the env var JAVA_HOME is set to the JDK install dir like mentioned here.

  2. MongoDB community edition. The software has been tested on Mongo v3.6.4. Earlier versions might not work due to loss of precision (Decimal128 was not introduced).

  3. leiningen which is used for dependency management like:

mkdir ~/bin
wget https://raw.githubusercontent.com/technomancy/leiningen/stable/bin/lein -O ~/bin/lein
chmod +x ~/bin/lein

For instance on Devuan systems one can install all necessary dependencies using apt and the following packages: apt-get openjdk-7-jdk libversioneer-clojure haveged.

Running the Social Wallet API

First of all check the configuration in resources/social-wallet-api.yaml and adjust its contents to your setup. Here a sample configuration:

# verbosity level of messages
log-level: debug

# open freecoin specific section
# indentation matters: mind the initial spaces of following sections
  # If an apikey is added to the config, for that particular installation an apikey will be created, stored and required with every request. Device-id should be replaced with the device/client-app name/id.
  apikey: device-id ## optional
# configuration for the database holding local transactions
    host: localhost
    port: 27017
    db:   freecoin
    currency: Commoncoin # You can set this to the name of the local currency to be used on the DB

## All the configurations below are optional and multiple can be added

# configuration of the 'faircoin' blockchain
# visualised name of the currency
    currency: fair
# number of confirmations to consider a transaction as valid
    number-confirmations: 6
# frequency of confirmations checks in milliseconds
    frequency-confirmations-millis: 20000
# path to the rpc configuration holding username and password
    rpc-config-path: /home/user/.faircoin2/faircoin.conf
# deposit to an address watch expiration time in milliseconds
    deposit-expiration-millis: 3600000
# frequency of deposit checks in milliseconds
    frequency-deposit-millis: 60000

# configuration of the 'bitcoin' blockchain
# visualised name of the currency
    currency: btc
# number of confirmations to consider a transaction as valid
    number-confirmations: 6
# frequency of confirmations checks in milliseconds
    frequency-confirmations-millis: 20000
# path to the rpc configuration holding username and password
    rpc-config-path: /home/user/.bitcoin/bitcoin.conf

Once correctly configured, from inside the social-wallet-api source directory one can use various commands to run it live (refreshing live changes to the code) using:

  • lein ring server (which will start and spawn a browser on it)
  • lein ring server-headless (will start without browser)

One can also use lein uberjar to build a standalone jar application, or lein uberwar to build a standalone war application ready to be served from enterprise infrastructure using JBoss or Tomcat.

Running the tests

To run all tests one need to run lein midje on the project dir

Run only the fast tests

Some of the tests are marked as slow. If you want to avoid running them you can either

lein midje :filter -slow

or use the alias

lein test-basic


Even though there are many ways to deploy this software, a dockerised version is provided in this project. For more details look into the docker folder. Please keep in mind that we do not recommend docker for production due to some security concerns.

🏁 Summary

This table summarizes which are the available methods for the different backends.

method database blockchain
tags.list βœ… 🚫
transactions(...).new βœ… 🚫
transactions(...).list βœ… βœ…
transactions(...).get βœ… βœ…
balance βœ… βœ…
label βœ… βœ…
address 🚫 βœ…
withdraws.new 🚫 βœ…
deposits.new 🚫 βœ…
deposits.check 🚫 βœ…

🍻 Articles & Guides

Who use the social wallet

  • Macao implemented the social wallet, with the goal to foster the sustainability of Milan cultural workers.
  • The Santarcangelo festival uses swapi to facilitate the token exchange during their amazing festival, leveraging both on smartphones and printed qrcodes

πŸ‘₯ Acknowledgements

The Social Wallet API is Free and Open Source research and development activity funded by the European Commission in the context of the Collective Awareness Platforms for Sustainability and Social Innovation (CAPSSI) program. Social Wallet API uses the underlying Freecoin-lib blockchain implementation library and adopted as a component of the social wallet toolkit being developed for the Commonfare project (grant nr. 687922) .

πŸ“„ License

This project is licensed under the AGPL 3 License - see the LICENSE file for details

Additional permission under GNU AGPL version 3 section 7.

If you modify Freecoin-lib, or any covered work, by linking or combining it with any library (or a modified version of that library), containing parts covered by the terms of EPL v 1.0, the licensors of this Program grant you additional permission to convey the resulting work. Your modified version must prominently offer all users interacting with it remotely through a computer network (if your version supports such interaction) an opportunity to receive the Corresponding Source of your version by providing access to the Corresponding Source from a network server at no charge, through some standard or customary means of facilitating copying of software. Corresponding Source for a non-source form of such a combination shall include the source code for the parts of the libraries (dependencies) covered by the terms of EPL v 1.0 used as well as that of the covered work.