How I Managed to Install a Workable GnuCash

There is a lot of advice here and elsewhere about how to install applications. Purism has taken steps to protect their users from any software that infringes on their privacy and freedom. That said, there are two points to be noted at the start:

  1. Purism says any debian package can be installed on PureOS. It’s in the FAQ.
  2. GnuCash already respects your privacy and freedom. And it supports online banking.

OK, so how can one install GnuCash? GnuCash must be the most difficult software package to install on any linux distro. I searched for .deb files. I found deb files that contained only source. No way I can do that. I found deb files that contained binaries. I downloaded gnucash, gnucash-common, gnucash-docs, aqbanking and everything else I could find and when I used apt to install i was left with uninstalled dependencies listing at about twenty yards of text output.
I tried flatpak. Everything worked like a charm, except that aqbanking and help files were not included. aqbanking is the external tool that GnuCash uses to do online banking.
The last step, which worked, was to add two repositories to Software & Updates. I think only the stretch repo was required for GnuCash 2.6.15 to be installed but it worked, installed all the dependencies and included online banking.
Adding a repo to PureOS is tricky. If the repo doesn’t work, the tool won’t tell you. If the repo does work, the entry in the Software & Updates changes its appearance and you are asked to update the new repo as you close the tool.
To install stretch:
Select Type as binary
Set the URI to http://deb.debian.org/debian (other URIs may also work)
Set the distribution to stretch
Set the components to main
Then close the tool selecting update option.
I used apt to install

sudo apt -s install gnucash
will let you test the install
sudo apt install gnucash
will do the installation

I also installed the testing repo with
Type set to Binary
URI set to http://ftp.us.debian.org/debian (other URIs may also work)
Set distribution to testing
Set components to main contrib

Trying to install using the term “buster” (which is the current testing) failed for me. I would recommend only installing the testing repo in case it is needed for gnucash, but I think gnucash is complete in the stretch repo. Stretch is the version of Debian prior to buster. Stretch is stable and buster is still in testing as it was explained to me.

So there you are. Getting GnuCash into the PureOS distro should not be too hard for Purism and it should happen as buster gets to stable, if I understand the progression. You only need to move your .gnucash file over to the librem to migrate from Windows. That one file contains all your accounts and transactions. You will have to setup your online banking again, so be sure to write down all the user and account info from your old installation on Windows.
To reiterate Purism’s position, adding software from these repositories might not respect your privacy and freedom. I’m only using them for GnuCash.

Online banking refused to work with gnucash on linux. So I ended up switching to kMyMoney which comes in the pureos repository. Online banking worked easily and I think I like it better. There should be something in the wiki along those lines.
I disabled the debian repositories and am using only the pureos repo.