Open Source is Awesome

At Knowm, we’re a big fan of open source. Like everyone else these days, we rely on it extensively from our operating systems to our applications. Even this website leverages open source! In July 2015, Knowm Inc. acquired Xeiam. Knowm is committed to maintaining and investing in the further development of XChange, XChart, Sundial, Yank and others and will keep the projects open source under the Apache 2 or MIT license. Knowm Inc. is financially supporting these projects with Bitcoin bounties as found below. Announcements for all projects will now appear on Knowm’s Twitter feed.

Xeiam to Knowm

Welcome PLOS One readers! Here’s the companion open-source code to the paper AHaH Computing – From Metastable Switches to Attractors to Machine Learning.

Open source software managed through distributed revision control systems like Git are a tremendously powerful way to develop software. Multiple eyes on code insures quality. Bugs are found and fixed. Code becomes modular and clear. Developers around the world keep the torch of innovation burning 24-hours a day, passing the project from one time-zone to another as dawn sweeps across the earth. Modern decentralized open-source software development is one of the most spectacular innovations in human history. At Knowm, we maintain several open source projects and regularly contribute to others as well. Check out our two main repos on Knowm and Timmolter. Below is a list of some of our most popular open source projects.

Open Source Java Projects


XChange is a Java library providing a simple and consistent API for interacting with 30+ Bitcoin exchanges providing a consistent interface for trading and accessing market data.


XChart is a light-weight and convenient library for plotting data. Its focus is on simplicity and ease-of-use, requiring only two lines of code to save or display a basic default chart. Usage is very simple: Create a Chart instance, add a series of data to it, and either save it or display it.


Sundial is a lightweight job scheduling framework for Java.. Sundial makes adding scheduled jobs to your Java application a walk in the park. Simply define jobs, define triggers, and start the Sundial scheduler.


XDropWizard is a jump-start DropWizard Web Application integrating and demonstrating several useful open source projects such as Yank, Sundial (a Quartz fork), Flot, Bootstrap, AngularJS, HSQLDB, XChart, JUnit, etc. Demonstrates how to serve static content, dynamic content loaded into Freemarker templates, using AJAX and more…


Yank is an ultra-Light JDBC persistance layer for Java apps. Never deal with the monotony and pitfalls of handling JDBC ResultSets and Connections again. Yank deals with connection pooling and table row to Java object mapping for you so you don’t have to worry about it.


AHaH! is a set of tools that can be used to solve a wide range of artificial intelligence and machine learning problems. All key functionality is based on operations that can be attained through use of an Anti-Hebbian and Hebbian (AHaH) Node. This is the companion open-source code to the paper AHaH Computing—From Metastable Switches to Attractors to Machine Learning, published on Feb. 10th, 2014 at PLOS One. All source code referenced in the paper can be found here.


Datasets is a a Java library for conveniently working with machine learning datasets. The philosophy of this open source project is simple – take several diverse datasets, which all have their own custom formats, and convert them all into a unified format with a unified API for accessing the data. Each module has a RawData2DB class, which parses the raw data and puts each data object into a file-based HSQLDB database. No separate database installation is necessary.


Memristor-Discovery is a Java application for automated memristor experiments and data collection based on Digilent’s Analog Discovery 2 USB Oscilloscope and Knowm’s Memristor Discovery Board.


JSpice is a SPICE-inspired analog circuit simulator made in Java with an emphasis on simulating memristors and analog circuits containing memristors..


Welcome to Knowm Inc.’s Bounty Program. Below is a listing of all our current open and past paid bounties. All bounties are paid in Bitcoin, and it’s by far the simplest and fastest way to transfer money in today’s globally connected international community. We’ll be posting all new bounties on our twitter feed, so please subscribe to be the first to hear about new bounties!

If you’d like to work on an issue for a bounty, the first thing you should do is claim it by adding a comment on the GitHub issue page where the bounty is defined along with how long you need to finish it. In this way, bounties can be claimed on a first-come first-served manner, but others may attempt it if the original claimer cannot finish it in a reasonable time. To claim the bounty, just leave your Bitcoin address as a comment on the GitHub issue page or in the pull request.

Donation Addresses

Please donate to this the following addresses to sponsor more bounties.

Coin Address Balance
Bitcoin 187sgF3x681fYCWGSUwYimd7xA4nXuzpbs 0.1596 BTC
Bitcoin Cash 1LoxGgVtbm1ZDPVm6578RLjWmFpTD7EpYe 0 BCH
Ether 0x056f4b575f64Fe016778CEfc32Adc59A30Df0892 0 ETH
Litecoin Lh5GWwLfaDMJYBWbri8xq9BuEvVwoJPmn8 0 LTC

100% of donations to open source projects will be directly recycled back into the project as a bounty or bounties. If you’re interested in donating or sponsoring a bounty for a specific feature request, please visit the project on GitHub where you can post a new issue with a bounty.


Task Reward Details Status
XChange General metadata improvements 10 mBTC GitHub Open


Task Reward Details Status
XChart Multiple X-Axes on One Chart 100 mBTC GitHub Paid
XChart Support Data labels 100 mBTC GitHub Paid
XChart New Bar Graph Style 100 mBTC GitHub Paid
XChart Support Stacked Bar Charts 200 mBTC GitHub Done
XChange Clean up AccountInfo 300 mBTC GitHub Paid
XChange Remove PollingTradeService deprecated getTradeHistory 300 mBTC GitHub Paid
XChange Refactor xchange-btce V3 module 25 mBTC GitHub Paid
XChange Refactor xchange-btcchina module 25 mBTC GitHub Paid
XChange Refactor xchange-bitstamp module 25 mBTC GitHub Paid
XChange Refactor xchange-kraken module 25 mBTC GitHub Paid
XChange Refactor xchange-mtgox polling V2 20 mBTC GitHub Paid
XChart Allow tilting of X-Axis labels 20 mBTC GitHub Paid