BUIP133: Electron Cash Ecosystem Improvements
Proposer: Jonald Fyookball (Sponsored by: imaginary_username and Andrew Clifford 3 Oct 2019)
Submitted on: 2019-11-09
Status: draft


The Electron Cash wallet is a focal point for the Bitcoin Cash
application layer. There are a number of projects that can add value and
strengthen the software and ecosystem, but currently most efforts are on
a volunteer basis. The Electron Cash group seeks $51,200 in order to
accomplish the following projects:


Project #1: “Faster SPV Server”

Get Electron Cash “talking” to electrs and/or bchd rather than just

Synopsis: ElectrumX is the server software that Electron Cash uses in
order to interact with the blockchain. It suffers from performance and
feature limitations, which either need to be fixed, or Electron Cash
should use other server software. It would be a good time investment to
get Electron Cash “talking” to other SPV services such as bchd or BU’s

Obstacles / Challenges / Goals: There is a very fast SPV server
implementation from BU called electrs but it still needs some feature
additions. Calin Culianu has offered to work with the BU team in ironing
out any final touches to get electrs to be at least as good or better
than ElectrumX in terms of featureset. Electrs, being entirely native
code, runs much faster than ElectrumX and is multi-core. It needs a few
niceties such as SSL support and “Server Federation” (creating a mini
p2p network of servers). This software is built-in to BU optionally and
thus has the potential to be installed on many full nodes on the
network. Additionally, bchd gRPC shows promise (is native, is fast, is
deployed in many places) but needs a few minor feature additions as
well. Working with these teams, Electron Cash could get them to the 100%
feature level needed – development and coordination time is needed.

Resources Needed: Development time from one or more of the Electron Cash
and/or collaboration with Dagurval or another BU developer and/or bchd
developers such as Chris Pacia.

Estimated Cost: 200+ hours developer time.

Project #2: “CashShuffle iOS”

CashShuffle is loved by all. It needs to come to Electron Cash’s iOS
implementation. Synopsis: The Bitcoin Cash ecosystem has by and large
had a positive reaction to Electron Cash’s CashShuffle. Many users are
asking for an iOS port of the subsystem to work in the existing Electron
Cash for iOS wallet app.

Resources Needed: Development time from Calin Culianu. Estimated Cost:
100 hours development time

Project #3: “Android Phase 4”

The Android version of Electron Cash has one more phase to complete its
core feature set. Finishing this brings the basic wallet to completion
and makes it ready for enhancements like SLP and CashShuffle/Fusion.

Synopsis: Here are the specific features being added:

  • Wallets:
    • Rename (including closed wallets)
    • Export (including closed wallets)
    • Delete (add ability to delete closed wallets)
  • Send:
    • Export and import unbroadcast transactions
  • Addresses
    • Freeze
    • Sign / verify
    • Private key
    • Encrypt / decrypt
  • Coins screen
  • Settings:
    • Transactions:
    • Use multiple change addresses
  • Show notification if payment received when app in background

Resources Needed: Development time from Malcolm Smith or other android
developer Estimated Cost: 100 hours development time

Project #4: “EC/SLP Merge”

SLP (Token) Integration into the Electron Cash main codebase and
discontinuing development on the EC-SLP Branch

Synopsis: The Electron Cash main codebase does not support
spending/creating SLP tokens. It needs this functionality, and the
Electron Cash SLP codebase needs to be discontinued, in the interests of
efficiency and simplicity for both users and developers.

Obstacles / Challenges: Careful review of the Electron Cash SLP pieces
that will be brought into Electron Cash must be done. Electron Cash
regular is a somewhat more complex wallet than EC-SLP, because of
CashShuffle, and care must be taken to not impact its performance needs.
Code review and rewriting of existing pieces from EC-SLP is anticipated,
as well as some reworking of the UI.

Resources Needed: Development time from one or more of the Electron Cash
and/or SLP developers such as Calin Culianu, James Cramer, Axel Gembe,
Mark Lundeberg or others.

Estimated Cost: 250-350 hours developer time.

Project #5: “Skin System”

A skinning system based on the existing ui’s QT framework. This allows
the wallet to have various designs and color themes. Synopsis: The idea
to create a skin system is not for novelty purposes. This actually is
our most viable idea for the Electron Cash developers create a business
model that will sustain development in the future. Everybody loves skins
and we will monetize it.

Resources Needed: Development time from Axel Gembe, Calin Culianu or
other QT specialist python developers.

Estimated Cost: 400 hours development time

Project #6: “SLP iOS”

Simple Ledger Protocol has taken the BCH world by storm. It needs to
come to Electron Cash’s iOS implementation.

Synopsis: Many users are asking for an iOS port of the subsystem to work
in the existing Electron Cash for iOS wallet app.

Resources Needed: Development time from Calin Culianu.

Estimated Cost: 200 hours development time

Project #7: “Private Reusable Addresses”

Make Electron Cash implement imaginary_username’s “reusable address”

Synopsis: Reusable addresses allow for an identifier such as a
CashAccount to be used to derive non-repeating addresses for discrete
repeated payments to the same person, using a new address each time, so
that one does not have to choose between privacy and usability - one can
have good privacy while only giving out an address just once. Enables
convenient, no-compromise handles for mass adoption.

Resources Needed: Development time from one or more of the Electron Cash
developers such as Calin Culianu, in conjunction with server-side work
such as bchd modifications from Josh Ellithorpe, as well as
specification/protocol work from imaginary_username.

Estimated Cost: 100-300 hours development time across multiple

Project #8: “Keyserver”

Allow Electron Cash to integrate with Cashweb’s Keyserver software.

Synopsis: Harry Barber and Shammah Chancellor have written “keyserver”
software for storing blockchain-related data in a separate peer-to-peer
network that is tightly integrated with the BCH blockchain.

Goals / Outcomes: This key piece of infrastructure allows wallets to
come alive. You can register data or share data with your friends all
from within your wallet. Send contact vCards or lookup your friend’s
aliases or addresses, send them instant messages, or store authenticated
data for sharing with others – all signed and associated with your
bitcoin address.

Resources Needed: Harry and Shammah are already developing the GUI
pieces needed for Electron Cash to integrate with this service, but more
development time from one or more of the Electron Cash developers such
as Calin Culianu would be helpful.

Estimated Cost: 50 hours development time.

Project #9: “More Robust and Private backend”

Make Electron Cash more robust against server withholding, leak less
privacy to its SPV servers.


A longstanding drawback of Electron Cash’s model of fetching all
transactions from a single server is that the server can withhold
transactions from the client, resulting in complications for receiving

On top of that, Electron Cash publishes its entire list of addresses to
a single server to which it connects, potentially leaking privacy to the
server which can trivially find address/spending linkages. Right now the
only real mitigation is via running your own server, Tor is a slight

Both of these can be fixed with a more intelligent strategy which it can
distribute load to add redundancy across servers, while not revealing
“too much” to any one server. Electron-cash then becomes more reliable
and robust for receiving payments.

Resources Needed: Development time from one or more of the Electron Cash
developers such as Calin Culianu.

Estimated Cost: 100-200 hours developer time.

Project #10 “Continuing Support and Protocol scalability”

Electron Cash needs constant upkeep and bug fixing. New libraries and
hardware wallets appear periodically and the code needs maintenance
frequently. It is a mostly volunteer effort but some funding would make
things much better. Apply unfinished protocol tweaks to enable massive


The Electron-Cash/Electrumx protocol contains a few weak points that
hinders its scalability, particularly when it comes to massive wallets
made more common by Cashshuffle, as well as big single-address wallets
common for commercial and donation uses. We have identified a few
protocol weak points such as transmission pagination and status update
algorithm that could use tweaking to prepare for better scaling, which
is in line with the BCH roadmap.

Resources Needed: Protocol discussion from Electron-cash developers, as
well as review from wider BCH development community

Estimated Cost: 100 hours of developer time

Cost Summary for all Projects:

Total cost: 1600-2000 hours of developer time. Discount rate: $32/hr @
1600 hours = $51,200

Jonald_fyookball and imaginary_username can report back on progress as
the goals are being fulfilled, members can also track them at
https://github.com/Electron-Cash/Electron-Cash. Even a part of the
goals should bring tremendous value to the BCH ecosystem, while the
funding brings stability and predictability to Electron-cash
development, which is currently largely staffed by volunteers.