Prime Specification

Functional

User

• sign up with e-mail activation and TOS acceptance
• sign in / out
• password reset
  • reset link valid for 24h or one use whichever comes first

Settings

• change password
• change email
• configure two factor authentication
• on/off API
• reset API key
• configure email notifications (TODO: details)
• complete account removal (privacy feature)
• all changes require second method authentication (email confirmation or OTP)

Dashboard

• change market; market is a pair of currencies, i.e. USD/BTC, PLN/BTC

Order book

• live chart
• live table

Last trades

• live chart
• live table

Account

• Balances for the current market
• History
  • every balance change must have a corresponding transaction
• Open orders
  • cancel order

Deposit

Bitcoins

• generation of personal input address
  • internal maintenance of user input addresses (every user has a list of input addresses)
• displaying address and instructions to the user
  • funding user balance with incoming bitcoins
    • create entry in account history, remember bitcoin tx id

Fiat

• internal (LAN-only) API for custom scripts to bump fiat balance
  • create entry in account history, remember fiat tx id

Withdraw

Bitcoins

• edit bitcoin output address
• confirm with e-mail link or Google Authenticator OTP
• displaying form to send bitcoins
  • amount
  • instructions and fee information
  • send button with summary and confirmation
• mechanism to actually send bitcoins
  • create entry in account history, remember bitcoin tx id

Fiat

• edit bank account details
• confirm with e-mail link or Google Authenticator OTP
• display form to send fiat
  • amount
  • instructions
  • send button with summary and confirmation
• add FiatWithdrawal entry to the list of pending fiat withdrawal requests
  • publish pending fiat withdrawals in internal API
  • accept request to mark specific FiatWithdrawal as fulfilled
    • create entry in account history, remember fiat tx id(?)

Buy/Sell

• Display "Please be aware this is only approximation. Order book can change every second."
• Validate order value denominated in fiat is high enough
  • This is to prevent order and transaction spam/DOS

Buy bitcoins

• Instant buy
  • "I want to buy [____] BTC instantly."
  • "You will spend about ____ USD and receive ____ BTC after fee. Average BTC price will be about ____ USD."
  • Technically equals to submitting buy order with infinite price.
• Buy with price limit
  • "I want to buy [____] BTC at price [____] USD/BTC."
  • "You will spend about ____ USD and receive ____ BTC after fee. Average BTC price will be about ____ USD."
  • "You need at least ____ USD at hand to submit this order."
  • Validate user has enough funds to submit the order (assuming worst case scenario)
  • Block funds
  • Match with existing orders
  • Smart defaults: max BTC user can buy, market price

Sell bitcoins

• Instant sell
  • "I want to sell [____] BTC instantly."
  • "You will receive about ____ USD after fee. Average BTC price will be about ____ USD."
  • Technically equals to submitting sell order with 0 price.
• Sell with price limit
  • "I want to sell [____] BTC at price [____] USD/BTC."
  • "You will receive about ____ USD after fee. Average BTC price will be about ____ USD."
  • Validate user has enough funds to submit the order
  • Block funds
  • Match with existing orders
  • Smart defaults: all BTC, market price

Fees

Transaction fee

Percentage and minimum fee denominated in fiat, like 0.6% min 0.01 USD. Taken from both sides of transaction from the output amount.

Bitcoin withdrawal fee

Percentage and minimum fee denominated in bitcoin, like 0% min 0.0005 BTC.

Fiat withdrawal fee

Percentage and minimum fee denominated in fiat, like 0% min 2 USD.

Public API

Ticker

TODO: design

Trades

As explained on bitcoincharts.

Order Book

As explained on bitcoincharts.

Admin panel

Stats

• Total funds on the exchange
  • Total funds accumulated on the exchange for each fiat (calculated from a database)
  • Total funds accumulated on the exchange for each cryptocurrency (calculated from a database)
• Hot wallets
  • Number and percentage of funds in a hot wallet (actual value taken from a bitcoind) for each cryptocurrency
• Number of users being online and total registered
• Number of buy and sell offers
• Number and volume of transactions

Export

• emails.csv

Actions

• Stop the service

Non functional

Supported browsers

Prime example fronted is tested on the latest versions of:

• Chrome
• Firefox
• Internet Explorer 9
• Opera

There is nothing that prevents you from creating a Prime fronted that supports older browsers (see design).

Correct use of HTTP protocol

• Semantic use of HTTP methods GET, POST, PATCH, DELETE
• Correct HTTP status codes

Take advantage of HTML5

• Use HTML5 to the full extent possible
• Aim at HTML5 validity

Limitation of v1.0

• While Prime is designed from ground up to support multiple cryptocurrencies, the first version will deliver integration only with bitcoin.
• No support for multiple hot and cold wallets. Only one pair of hot/cold wallet will be supported.

Open questions

• Checking whether actual crypto and fiat balances cover values from a database (prevent fractional reserve)? How to do it correctly (i.e. delays in transfers, etc)?