Freecoin is a set of tools initially designed to let people run reward schemes that are transparent and auditable to other organisations. It comprises of an electronic wallet and other side products which are designed to be generic and they can facilitate multiple blockchains, offline transactions, identity management and multi-signature authentication. The toolkit is written in Clojure and in this talk I will touch technical details about the design, the interaction with blockchain nodes as well as some more theoretical background and the empirical research that the products is based on.

1. A complementary currency toolkit in
Clojure
Aspasia Beneti
AMSTERDAM | MAY 8-9, 2018

2. @aspra
Aspasia Beneti
https://github.com/aspasia
INTRODUCTION
Social Wallet
A complementary currency toolkit
2

3. Digital community and
free software foundry
Our mission
Dyne.org is a non-profit free software foundry
with more than 15 years of expertise in
developing tools and narratives for community
empowerment.
Dyne.org
3

4. “WE ARE FREE TO SHARE CODE AND WE CODE TO SHARE
FREEDOM .”
— DYNE.ORG
4

5. Dyne projects

6. European projects

7. 7
SUPPORT

11. Can we use the Blockchain to
empower communities?
?

12. “A blockchain, originally block chain, is a continuously growing
list of records, called blocks, which are linked and secured using
cryptography. .”
— Wikipedia.org
12

13. What is a blockchain good for?
●
Decentralized Internet
●
Decentralized market places
●
Smart contracts
●
Distribute foreign aid
●
???

16. How can we use technology to
create complementary currencies
and reward schemes?
?

17. What is a complementary currency?
A complementary currency is a currency or medium of exchange which is not a
national currency, but which is thought of as supplementing or complementing
national currencies.

19. Why complementary currency?
●
Keep value circulation locally
●
Protects against instability global markets
●
Sense of community and trust
●
Reduces ecological footprint

20. How do we know what communities
need
!

21. Collecting requirements
●
Academic research
●
Participatory design
– Pilot partners
– Working with people and communities

22. The pilots
 Italy
•
Basic Income Network
•
Macao
 Croatia
•
Centre for peace studies
 Netherlands
•
Museu da Crise
●
Amsterdam - freelancers
●
Rotterdam - welfare recipients
●
The Hague – immigrants
•
Faircoin node Amsterdam

23. Commonfare platform

24. Macao Milan

25. Santarcangelo festival

26. Requirements

Integration Commonfare CMS

Not always need for a blockchain

Multiple blockchain backends

Vouchers

Multi-signature transactions

Deposit/withdraw

Stats, analysis

Authentication

Configurable

Internally transparent

Administration and self-
monitoring by communities

27. The social wallet toolkit
A collection of open source software modules written in Clojure

28. Social Wallet toolkit
 Macao Social Wallet
 Freecoin-lib
 Social wallet api
 Two factor authenticator
 Secrets/Fxc
 Admin console
 clj-storage

29. Why Clojure?
● LISP
● JVM/Java Interop
● Homogeneous
● Immutability is the default!
● Functions first class citizens
● Concurrency
● Clojurescipt
● REPL

30. Too many parenthesis!

31. Freecoin lib
Blockchain protocol
•
DB based
•
RPC for bitcoin derivatives
•
In Memory

32. Macao wallet
- Simple Liberator WebApp
- Authentication, transactions, tags, balance, Qrcodes
- DEMO!

33. Social wallet API
- Swagger API wrapping the freecoin-lib
- Includes logic that maps RPC transactions to DB
- DEMO!

34. Two factor authentication

Abstract 2 step auth

Configurable throttling behavior

Password encryption using pbkdf2+sha512

35. Fxc

Encode: splits a secret string in multiple parts

Decode: recover using n of those parts (quorum)

Generate: Generates a random password of type and size

36. Secrets

Desktop App wrapping FXC

Webapp wrapping FXC
 Demo!

37. Admin Console

Dynamic configuration console for admins

Stats and configs

Gorilla repl

Incanter for plotting

38. Clj storage

Storage abstraction
●
MongoDB
●
Filesystem - Nippy

Some convenience test storage functions

39. WHAT ABOUT EXISTING
CRYPTOCURRENCIES?
?

40. Consensus algorithms

41. Faircoin 2

42. Proof of cooperation
●
Cooperation instead of competition
●
Cooperatively Validated Nodes (CVNs)
●
EC-Schnorr multi signature algorithm

43. CAN I HAVE A LOOK AT THE CODE?
Sure thing!
https://github.com/Commonfare-net
!

44. “PUBLIC CODE PUBLIC MONEY”
— publiccode.eu
44

45. Lessons learned
What we have learned so far ...
!

46. 
Currency (numerical precision)

Large monolithic apps

Depending on proprietary software

Depend on libs that do much more than needed

Early adoption of tech
 Don’t solve problems before the arise!

47. Still on the doing:
●
Multi-signature
●
API Key
●
Vouchers
●
Brute force attack authentication lib
●
Out of the box solution for communities to create own currency

48. Why are you telling us all this?
?

49. Riace

50. Riace currency

51. Technology can be used for the
common good
SO WHY SHOULD I CARE ABOUT
THIS
The blockchain is a diverse tool which we can utilize to improve our lives.
Lets get creative!
?