Gittip is a platform for sustainable crowd-funding.
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This is Gittip, a sustainable crowd-funding platform.

The basis of Gittip is an anonymous gift between $1 and $24 per week to someone who does great work. These gifts come with no explicit strings attached.

The Gittip gift exchange happens every Thursday. On Thursday, we charge people's credit cards and the money goes into a marketplace account with Balanced Payments. Money is allocated to other participants, and for those with a bank account attached and money due, the money is deposited in their bank account on Friday.

Gittip is funded on Gittip.

Table of Contents


Thanks for hacking on Gittip! Be sure to review CONTRIBUTING as well if that's what you're planning to do.


Gittip is built with Python 2.7 and the Aspen web framework, and is hosted on Heroku. Balanced is used for payment processing, and Google for analytics.

You need python2.7 on your PATH.

You need Postgres. We're working on porting Gittip from raw SQL to a declarative ORM with SQLAlchemy. After that we may be able to remove the hard dependency on Postgres so you can use SQLite in development, but for now you need Postgres.

The best version of Postgres to use is 9.2, because that's what is being run in production at Heroku. Version 9.1 is the second-best, because Gittip uses the hstore extension for unstructured data, and that isn't bundled with earlier versions than 9.1. If you're on a Mac, maybe try out Heroku's If installing using a package manager, you may need several packages. On Ubuntu and Debian, the required packages are: postgresql (base), libpq5-dev (includes headers needed to build the psycopg2 Python library), and postgresql-contrib (includes hstore).

Now, you need to setup the database.

Setting up the Database

Once Postgres is installed, you need to configure authentication and set up a gittip database.


If you already have a “role” (Postgres user) that you'd like to use, you can do so by editing DATABASE_URL in the generated local.env file. You can also change the database name there. See Configuration for more information.

Otherwise, you should add a role that matches your OS username, and make sure it's a superuser role and has login privileges. Here's a sample invocation of the createuser executable that comes with Postgres that will do this for you, assuming that a “postgres” superuser was already created as part of initial installation:

$ sudo -u postgres createuser --superuser $USER

Set the authentication method to “trust” in pg_hba.conf for all local connections and host connections from localhost. For this, ensure that the file contains these lines:

local   all             all                                     trust
host    all             all               trust
host    all             all             ::1/128                 trust

Reload Postgres using pg_ctl for changes to take effect.


Once Postgres is set up, run:

$ ./

That will create a new gittip superuser and a gittip database (with UTC as the default timezone), populated with structure from ./schema.sql. To change the name of the database and/or user, pass them on the command line (you'll need to modify the DATABASE_URL environment variable as well; see Configuration below):

$ ./ mygittip myuser

If you only pass one argument it will be used for both dbname and owner role:

$ ./ gittip-test

The schema for the database is defined in schema.sql. It should be considered append-only. The idea is that this is the log of DDL that we've run against the production database. You should never change commands that have already been run. New DDL will be (manually) run against the production database as part of deployment.

Building and Launching

Once you've installed Python and Postgres and set up a database, you can use make to build and launch Gittip:

$ make run

If you don't have make, look at the Makefile to see what steps you need to perform to build and launch Gittip. The Makefile is pretty simple and straightforward.

All Python dependencies (including virtualenv) are bundled with Gittip in the vendor/ directory. Gittip is designed so that you don't manage its virtualenv directly and you don't download its dependencies at build time.

If Gittip launches successfully it will look like this:

$ make run
./env/bin/swaddle local.env ./env/bin/aspen \
                --www_root=www/ \
                --project_root=.. \
                --show_tracebacks=yes \
                --changes_reload=yes \
[SWADDLE] Skipping line: .
[SWADDLE] Skipping line: .
[SWADDLE] Skipping line: .
[SWADDLE] Skipping line: .
[SWADDLE] Skipping line: .
pid-12508 thread-140735090330816 (MainThread) Reading configuration from defaults, environment, and command line.
pid-12508 thread-140735090330816 (MainThread)   changes_reload         False                          default                 
pid-12508 thread-140735090330816 (MainThread)   changes_reload         True                           command line option --changes_reload=yes
pid-12508 thread-140735090330816 (MainThread)   charset_dynamic        UTF-8                          default                 
pid-12508 thread-140735090330816 (MainThread)   charset_static         None                           default                 
pid-12508 thread-140735090330816 (MainThread)   configuration_scripts  []                             default                 
pid-12508 thread-140735090330816 (MainThread)   indices                [u'index.html', u'index.json', u'index'] default                 
pid-12508 thread-140735090330816 (MainThread)   list_directories       False                          default                 
pid-12508 thread-140735090330816 (MainThread)   logging_threshold      0                              default                 
pid-12508 thread-140735090330816 (MainThread)   media_type_default     text/plain                     default                 
pid-12508 thread-140735090330816 (MainThread)   media_type_json        application/json               default                 
pid-12508 thread-140735090330816 (MainThread)   network_address        ((u'', 8080), 2)        default                 
pid-12508 thread-140735090330816 (MainThread)   network_address        ((u'', 8537), 2)        command line option --network_address=:8537
pid-12508 thread-140735090330816 (MainThread)   network_engine         cherrypy                       default                 
pid-12508 thread-140735090330816 (MainThread)   project_root           None                           default                 
pid-12508 thread-140735090330816 (MainThread)   project_root           ..                             command line option --project_root=..
pid-12508 thread-140735090330816 (MainThread)   renderer_default       tornado                        default                 
pid-12508 thread-140735090330816 (MainThread)   show_tracebacks        False                          default                 
pid-12508 thread-140735090330816 (MainThread)   show_tracebacks        True                           command line option --show_tracebacks=yes
pid-12508 thread-140735090330816 (MainThread)   unavailable            0                              default                 
pid-12508 thread-140735090330816 (MainThread)   www_root               None                           default                 
pid-12508 thread-140735090330816 (MainThread)   www_root               www/                           command line option --www_root=www/
pid-12508 thread-140735090330816 (MainThread) project_root is relative: '..'.
pid-12508 thread-140735090330816 (MainThread) project_root set to /Your/path/to/
pid-12508 thread-140735090330816 (MainThread) Renderers (*ed are unavailable, CAPS is default):
pid-12508 thread-140735090330816 (MainThread)   TORNADO          
pid-12508 thread-140735090330816 (MainThread)  *pystache         ImportError: No module named pystache
pid-12508 thread-140735090330816 (MainThread)   stdlib_template  
pid-12508 thread-140735090330816 (MainThread)   stdlib_format    
pid-12508 thread-140735090330816 (MainThread)  *jinja2           ImportError: No module named jinja2
pid-12508 thread-140735090330816 (MainThread)   stdlib_percent   
pid-12508 thread-140735090330816 (MainThread) Starting cherrypy engine.
pid-12508 thread-140735090330816 (MainThread) Greetings, program! Welcome to port 8537.
pid-12508 thread-140735090330816 (MainThread) Aspen will restart when configuration scripts or Python modules change.
pid-12508 thread-140735090330816 (MainThread) Starting up Aspen website.

You should then find this in your browser at http://localhost:8537/:


Congratulations! Sign in using Twitter or GitHub and you're off and running. At some point, try running the test suite.


If you get stuck somewhere along the way, you can find help in the #gittip channel on Freenode or in the issue tracker here on GitHub. If all else fails ping @whit537 on Twitter or email

Thanks for installing Gittip! 😃


When using make run, Gittip's execution environment is defined in a local.env file, which is not included in the source code repo. If you make run you'll have one generated for you, which you can then tweak as needed. Here's the default:


The BALANCED_API_SECRET is a test marketplace. To generate a new secret for your own testing run this command:

curl -X POST | grep secret

Grab that secret and also create a new marketplace to test against:

curl -X POST -u <your_secret>:

The site works without this, except for the credit card page. Visit the Balanced Documentation if you want to know more about creating marketplaces.

The GITHUB_* keys are for a gittip-dev application in the Gittip organization on Github. It points back to localhost:8537, which is where Gittip will be running if you start it locally with make run. Similarly with the TWITTER_* keys, but there they required us to spell it

You probably don't need it, but at one point I had to set this to get psycopg2 working on Mac OS with EnterpriseDB's Postgres 9.1 installer:


If you wish to use different username or database name for the database, you should change the DATABASE_URL using the following format:

DATABASE_URL=postgres://<username>@localhost/<database name>

Testing Testing

Please write unit tests for all new code and all code you change. Gittip's test suite is designed for the nosetests test runner (maybe it also works with py.test?), and uses module-level test functions, with a context manager for managing testing state. As a rule of thumb, each test case should perform one assertion.

Assuming you have make, the easiest way to run the test suite is:

$ make test

However, the test suite deletes data in all tables in the public schema of the database configured in your testing environment, and as a safety precaution, we require the following key and value to be set in said environment:

YES_PLEASE_DELETE_ALL_MY_DATA_VERY_OFTEN=Pretty please, with sugar on top.

make test will not set this for you. Run make tests/env and then edit that file and manually add that key=value, then make test will work. Even just importing the gittip.testing module will trigger deletion of all data. Without this safety precaution, an attacker could try sneaking import gittip.testing into a commit. Once their changeset was deployed, we would have ... problems. Of course, they could also remove the check in the same or even a different commit. Of course, they could also sneak in whatever the heck code they wanted to try to sneak in.

To invoke nosetests directly you should use the swaddle utility that comes with Aspen. First make tests/env, edit it as noted above, and then:

[gittip] $ cd tests/
[gittip] $ swaddle env ../env/bin/nosetests


The Gittip API is comprised of these endpoints:

  • /about/paydays.json (source)—Returns an array of objects, one per week, showing aggregate numbers over time. The charts page uses this.

  • /about/stats.json (source)—Returns an object giving a point-in-time snapshot of Gittip. The stats page displays the same info.

  • /%participant_id/public.json (example, source)—Returns an object with these keys:

    • "receiving"—an estimate of the amount the given participant will receive this week

    • "my_tip"—logged-in user's tip to the Gittip participant in question; possible values are:

      • undefined (key not present)—there is no logged-in user
      • "self"—logged-in user is the participant in question
      • null—user has never tipped this participant
      • "0.00"—user used to tip this participant
      • "3.00"—user tips this participant the given amount


Account Elsewhere - An entity's registration on a platform other than Gittip (e.g., Twitter).

Entity - An entity.

Participant - An entity registered with Gittip.

User - A person using the Gittip website. Can be authenticated or anonymous. If authenticated, the user is guaranteed to also be a participant.

See Also

Here's a list of projects we're aware of in the crowd-funding space. Something missing? Ping @whit537 on Twitter or edit the file yourself (add your link at the end). 😀

Note: there are comprehensive directories that can complement this list, such as's and's