• cloud.sagemath.com
• github

• William Stein, University of Washington -- Most coding and design
• Harald Schilly, Vienna, Austria -- Marketing and QA; some frontend coding
• Keith Clawson -- Hardware/infrastructure
• Jon Lee, University of Washington -- frontend work, history viewer
• Andy Huchala, University of Washington -- frontend work, bug finding
• Nicholas Ruhland, University of Washington -- frontend work, tab reordering and resizing

SMC is open source, released under the GNU General Public License:

Copyright (C) 2014, William Stein

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

See the file build.py.

• python-daemon -- http://pypi.python.org/pypi/python-daemon/; Python license, and will go into Python eventually
• paramiko -- http://www.lag.net/paramiko/; ssh2 implementation in python
• cql -- interface to Cassandra database

• CoffeeScript -- all our Javascript is written using CoffeeScript
• jQuery, jQuery-ui -- http://jquery.org/; MIT license
• twitter bootstrap -- apache license
• codemirror2 -- http://codemirror.net/; basically MIT license
• jquery activity indicator -- MIT license
• Primus
• and many, many more!

• Many, many npm modules; see build.py

• Cassandra -- Apache licensed

• Linux -- SMC is only designed to be run on Linux (GPL v2)
• tinc -- VPN software; http://www.tinc-vpn.org/; GPL v2+
• Git -- http://git-scm.com/; GPL v2
• Sage -- http://sagemath.org/; GPL v3+; this is linked by sage_server.py, which thus must be GPL'd
• ZFS -- filesystem; CDL license

• VPN -- tinc; P2P vpn; connects all computers at all sites into one unified network address space with secure communication
• SSL -- stunnel
• Client -- javascript client library that runs in web browser
• Load balancer-- HAproxy
• Database -- Cassandra; distributed, NoSQL, fault tolerant, P2P
• Compute -- VM's running TCP servers (e.g., sage, console, projects, python3, R, etc.); stores all project data using ZFS.
• Hub -- written in Node.js; primus server; connects with everything -- compute servers, Cassandra DB, other hubs, and clients.
• HTTP server -- Nginx static http server
• admin.py -- Python program that uses the paramiko library to start/stop everything
• Private Cloud-- (mostly) kvm virtual machines in various places
• Public Cloud -- Google Compute Engine

   Client    Client    Client   Client  ...
     /|\
      |
   https://cloud.sagemath.com (stunnel, primus)
      |
      |
     \|/
 HAproxy (load balancing...)HAproxy                  Admin     (monitor and control system)
 /|\       /|\      /|\      /|\
  |         |        |        |
  |http1.1  |        |        |
  |         |        |        |
 \|/       \|/      \|/      \|/
 Hub<----> Hub<---->Hub<---> Hub  <-----------> Cassandra <--> Cassandra  <--> Cassandra ...
           /|\      /|\      /|\
            |        |        |
   ---------|        |        | (tcp)
   |                 |        |
   |                 |        |
  \|/               \|/      \|/
 Compute<-------->Compute<-->Compute <--- rsync replication  --->  Compute ...
  ZFS snapshots