Snap package development workflow

Martin Albisetti martin.albisetti at
Thu Apr 16 16:43:29 UTC 2015

On Thu, Apr 16, 2015 at 3:18 AM, "Thomas B. Rücker" <thomas at> wrote:
> Hi,
> I started looking deeper into core and snappy recently.
> tl;dr: How do I set up a development workflow with up to date tools and
> images. Sign packages? Import keys into core images?
> One thing I did was to try and get a feeling for things, so I decided to
> "follow the exact steps".
> I started at and went down the rabbit hole.
> At I decided to
> go with the KVM image and downloaded alpha2.
> Then I followed the link to .
> At that point I did update the image as told and half the commands
> stopped working as the new release uses a different syntax.
> Also the mentioned rollback failed: "Unable to determine bootloader"

Right, we are pushing to release a stable version of Snappy soon, so
there's some intermittent breakage, sorry.
This will be fixed soon and you will have a stable version of Snappy
to use, or a devel branch that changes daily.

> As described in the following part of that website, I tried to deploy
> the "hello world" example next:
> /******/
> /$ snappy-remote --url=ssh://ubuntu@ install
> ./hello-world.canonical_1.0.5_all.snap/
> /=======================================================/
> /Installing ./hello-world.canonical_1.0.5_all.snap from local environment/
> /ubuntu at's password:/
> /ubuntu at's password:/
> /ubuntu at's password:/
> /issues while running ssh command: Installing
> /tmp/hello-world.canonical_1.0.5_all.snap/
> /Signature verification failed with exit status 10
> ******
> /I then found out about:

While that bug is fixed, you can copy the snap package to the device,
ssh in and run snap install --allow-unauthenticated, rather than

> But that doesn't really help as there is no obvious way to put the image
> in a "developer mode". Why is such a demo image not in developer mode
> anyway?

I'll let Sergio, Loic or Michael reply here.

> If you don't upgrade the image then it will install if you enter the
> password several times, but why does the guide tell you to upgrade then?
> What bugs do I have to live with in alpha2? Why is the upgrade breaking
> things?

We are putting in place continuous integration and regression tests to
ensure this stops

> I went on IRC and asked for help, but nobody answered my question. Ogra
> replied but couldn't help. (I did not leave after 23 seconds and took
> the liberty to repeat part of my question after 10 hours or so.)
> I also queried the web search engine of my least distrust on the above
> topics but couldn't locate solutions nor different TFM than named before.

The Snappy team is currently sprinting together in the US, heads down
trying to fix many of the problems you describe above, so we haven't
been able to keep up with IRC.


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