email_merger is a simple program for sending out customised e-mails, using Makefile-esque substitution on a template e-mail, to multiple addresses.


email_merger is released under a BSD / MIT style licence.

Download email_merger 0.7 (8 April 2007) (5Kb)

You can also view email_merger's online git repository. Patches are always gratefully received.

Detailed description

email_merger is a simple program for sending out customised e-mails. It takes in a template e-mail and a TSV (Tab Separated Value) substitution file. The field names in the TSV file are substituted, using Makefile-esque syntax, in the template e-mail. Multiple e-mails can be sent, and each e-mail can be addressed to multiple people. E-mails are sent using the local sendmail program.

The template file should be a properly formatted e-mail message e.g. one or more headers followed by a blank line and then the message body. Substitution can occur in both the header and message body. A sample template file looks as follows:

From: Firstname Lastname <>
To: ${EMAIL}
Subject: Test

Dear ${NAME},

Blah blah blah

Keys are identified in the template file by the syntax ${X} where X is a name satisfying the following regular expression [_0-9a-zA-Z]+.

The substitution file starts with a tab separated list of substitution names which define keys which will be replaced in the template. Each subsequent line of the substitution file specifies particular values for these keys. Blank lines in the substitution file are ignored. A new e-mail will be generated and sent for each line in the substitution file.

If the -e flag is specified, each substituted e-mail is then passed to $EDITOR for editing. The user may edit any part of the e-mail, including the headers.

After substitution and any subsequent editing has occurred, the following headers are added to the outgoing e-mail if they are not present in after substitution:

Date: <date>
User-Agent: email_merger 0.07 (2007/04/08)
Note that if BCC header(s) are specified, they are stripped before the e-mail is sent.


Dummy run. Do everything except send e-mails.

Individually edit each e-mail with $EDITOR before it is sent.

-o <dir>
Save each e-mail being sent into dir.


email_merger can be customised via the optional $HOME/.email_merger file, which is a normal Python file. The following variables may be set:

sendmail. Default: /usr/sbin/sendmail -oem -oi
The location of the sendmail binary. To send e-mail via a remote machine, one can use ssh e.g. /usr/bin/ssh -q -C -l myusername /usr/sbin/sendmail -oem -oi

post_sendmail_delay. Default: 1
The length of time to delay, in seconds, after sending each e-mail.


email_merger is written in Python and therefore requires Python to be installed on your local computer. The email_merger Python script can then be copied to anywhere in $PATH.