It can be hard for an addon developer to keep an addon compatible with all permutations and combinations of c5 versions, other addons, and host environments.

Even those of us that are very proactive about supporting addons cannot achieve perfection all of the time. That is just the nature of software.

So:

1. If an addon developer does not respond to pre-sales questions, do not buy with any false expectation. That is common sense. If someone does not respond to a pre-sales question, can you expect them to respond to post sales support request?

2. If an addon developer supplies an addon in good faith, and you experience problems, open a support request and give them a chance to work with you to solve the problems.

3. The c5 marketplace includes a refund policy for marketplace addons. If after purchasing, then giving a developer a chance to help solve problems, it still does not work out, then a good developer should offer you a refund or support your request for a refund. But please give a developer a chance to solve any problems first. Also, please bear in mind that the issue may not be with that specific addon, but with a previous addon that has broken the rules. The ideal is that you purchase in good faith and developers supply in good faith.

4. When a new version of c5 is released, there are invariably stability issues for some sites. All of us (developers, site owners etc.) need to give each other an opportunity to resolve such issues. Such a cooperative attitude is (to me) what open source software is all about. We may gripe, but collectively we need to work together to solve it.

5. Unfortunately there will always be some addons in the marketplace that have effectively been abandoned or neglected by their developers (as per 1). That is an unfortunate reality of any marketplace such as concrete5. Collectively, we need to identify such addons. In some cases another developer can take them over and continue support and development.

6. If, after all that, something does still not work and cannot be resolved, then Frnz et.al at concret5 will enforce a refund.

Ofcourse, I agree with every point you made. And my initial post I probably should have been a bit more specific. I actually thought to go back and edit, but was hoping that one would assume that, for instance, an addon not working 'due to my environment, or changes I have made that function outside of the way the core does' could cause the addon to not work in MY case, is obviously an issue that I wouldn't and couldn't hold the dev responsible for.
I was meaning much more narrow as in the addon right out of the box didn't work with say 5.6 when it was 100% with earlier C5 ver. How would something specific as that be handled. Like, I already have my list of your addons at the top of my priority list :) And seeing that you are active as well as responsive to presales, well, there's no question I'm getting them.. hell, the Magic Data for a person like myself with no strong knowledge of ajax / js will have me toying for days with some of the things I can accomplish now lol!
So, I totally get the points you made, but like said previously, my points were a bit more narrow in reference to addons that maybe dont work right out of the box and not working with no alterations of C5 core or any overrides etc.

I still do think that per addon page should supply those looking to purchase to:
1. Have a way to bookmark them as favs / watch list (I'm doing it with my browser bookmarks), but I think being able to have a list in the 'my C5 account profile' situation would be faster and more intuitive.
2. Indication of some sorts as to last or most recent vers of C5 is the addon KNOWN to be 100% with.
3. Optionally, dated release notes / version history would be ideal. Could also indicate, 'this addon MAY just be out-dated' because it hasn't been updated or version history says 2011. Ofcourse that doesn't mean it doesn't work or couldn't even be made to work.. it would just let me know that maybe I could purchase this other more recently updated addon that's similar to what I need from that out-dated one.
4. Optionally, if one could click a C5 version, say 5.6, and just the addons where dev indicates "This works with this version and lower", would be great.


I say this because not only have I been going through EVERY page of the docs numerous times, yours aswell JTF, before I jump into C5 like a cannonball dive.. I'm looking at every addon to see which ones, in 'my' case, will save me development time. And this is the one nagging thing about the addons portion that has me pondering, "Will this addon actually work with my core 5.6.2 my core 5.7" When infact, it stopped working with 5.4.
So it's not so much will I get my money back, whats way more important is I can't get the time back.. if you understand my point.

Something that John forgot to mention is that add-ons are developed for a minimum version of C5 meaning we have to specify the oldest version of C5 it will work with but not the newest. We have to do that in the market place but also in the code. The only way to tell users if it's compatible with the latest is to add a mention manually on the add-on page. And as John pointed out that can be a daunting task for someone with many add-ons especially complex ones.

Forgive me if I'm not totally understanding, and am honestly not trying to be difficult, but your comment has now peaked a curiosity outside of something as simple as if an addon doesn't work does one get a refund, I'm totally understanding that issue.

But in reference to your comment, specifically you said
I'm confused, your saying that when you dev a new addon you build it with precedence for an older version of C5 vs the latest version going backwards? I say I'm confused because if that's the case, that would leave a good amount of addons 'not working' for the later or latest versions of C5, especially if the core version has major changes or what about code that gets deprecated?

Also, you said,
Forgive me, but thats a bit disturbing. I mean I totally get what your saying about it being a task to insure that a multitude of addons that you created may not work with the latest vers C5, atleast until you had the time to go through it and actually as the dev confirm it. BUT, when you put yourself in the shoes of a 'paying customer' or 'potential customer' of your addon, wouldn't you want to actually know that this not gonna work for me, and I'm talking about may not even work with the core C5.. and I won't know until after it's paid for. I mean thats literally like buying tires for a car, and not knowing there gonna fit until you've actually removed the others and are going to put the new ones on.. vs 'knowing' the size, and thus knowing exactly what tires to purchase.


My point is after reading your comment, when I look at the addons now, unless the dev actually states hey this works with vers x and earlier, theres a good chance that that addon may not work with my 5.6.2, and possibly a number of versions earlier? Meaning, I would buy it 'to see if it will work with my latest version of C5'?
Like I said, I get where your coming from, as a developer, but if this is the case, the least that should be at each addon's page is the version(s) it was/is working with confirmed by C5 devs or the addon's dev.

And please keep in mind the view of a user who says well let me build with C5, and looks to purchase addons, 'without' the notes that you and John have just pointed out. That could be a dilemma for someone, IF these points aren't stated there at the addon's page. Would you not agree, from the perspective of a new user to C5 and not the knowledgable dev that you and John are?

Lastly, I totally get that C5 and even the addons are ever evolving, probably on the daily basis.. I get that, but at the same time, so should other things that come along with the greatness of C5. I mean me, personally, I'm already sold lol! I would just hope that points like this do make it into what's obviously not code of C5, but is definitely an issue of C5 + addons. Because at the core (pun intended) of my point, is when one visits the addons page(s), without text saying otherwise, I 'was' and 'was assuming' that XYZ Addon would work with my C5 5.6.2!

I have read what you're saying, but it seems to me you're coming at the question from quite the wrong angle. I'm not an add-on developer, but I am a user, and I have bought a number of add-ons for a number of sites so far.
So bear with me from my users perspective. Where I have been up for purchasing an add-on, like John says, look at if the developer is active - see if they're still using the forums, and if necessary, ask a pre-sales question to make sure they're there. You could even ask if their add-on is compatible with the version of C5 you're using.
Outside of this, my experience has been that generally speaking, if the developer is responsive, and the minimum version stated for the add-on is lower than what you're using, it's safe to buy. Why? Because most add-ons will work no problems with later versions of concrete, and if they don't, the developer will work with you to resolve the problem or if worst comes to worst, refund your money. That is my experience.
Just yesterday, I upgraded one of my sites to the latest concrete version, and it affected part of how one of my add-ons worked. I immediately reported the issue on the add-on support page, and within a few hours the developer had been in touch with a temporary fix until the issue was diagnosed and fixed in the add-on code.
So I guess what it comes down to is that my approach presumes that given the conditions above, the add-on will work for me, rather than presuming that it won't work simply because the version of concrete I am using is newer than the minimum version stated.

Sorry I was not very clear in my explanation. What I meant is that when writing an add-on and submitting it to the market, we have to specify what is the oldest version of C5 the add-on will work with. That's why on the marketplace it states that the addon is compatible with 5.4+ or 5.5+. This allows your C5 install to check and to tell you whether your version can handle the add-on or not.

Now when we submit an addon to the marketplace, it goes through a rigorous check and it is tested against all the versions of C5 we said it worked with. The understanding is that the addon also works with the latest version of C5 AT THE TIME OF SUBMISSION. But because C5 evolves constantly, that can change.

However, C5 core doesn't go through drastic changes all the time. For instance, if an addon says it's compatible with 5.5 and up you can be sure that 99.9% of the time it is still ok with 5.6. If the addon says compatible with 5.4 and up there will probably problems because there are big differences between 5.4 and 5.5.

Ultimately, as John and Stretchrt have pointed out, communication with the developer is important in any case and a slow or non reponsive developer is a sure sign that you shouldn't buy the addon. Also having a message from the developer saying his addon is compatible with your version is an excellent to get your money back later on if the claim was erroneous.

To use your car image, every time you decide to buy the latest model, you don't know if the old model of wheels you use to use is still going to work for you. Except in this case, if the old model doesn't fit you still have a chance to get your money back.

Mnakaly and stretchrt have made all he points that need to be made here.
With 5.6.1.1 and then 5.6.1.2 coming out within a few days of each other, It will be a few days more before I can say categorically that all of my addons are 100% compatible. But they are all already tested in 5.6.1, so I don't anticipate needing to make any changes.

From 5.4 to 5.5, then 5.5 to 5.6, there were a lot of core changes to the way dashboard pages rendered, so I had quite a job on my hands at each of those c5 updates.

When 5.7 is released, I anticipate having to work on the edit dialogs of my addons to take advantage of the core improvements.