I'm considering becoming a full time indie game developer within the next two years. I plan to perform most of the work myself. I work as a programmer and would likely use Unity to create a 2D side scrolling game. I've been working on my artistic skills for the last 6 years, so I plan to create the art as well.

The main concern I have is the possibility of getting in over my head. What I need to know is what's a feasible scope of game for one person to complete in 12-15 months? Are their any examples of indie 2D side scrolling games created by one developer within that time frame?

One bit of advice I learned several years ago is to grow into this gradually.

Estimate what you can do in one month. Then set a date of 30 days away. Build your project for 30 days. When you get to the end of 30 days, stop.

Evaluate what you did in 30 days. DO NOT CONTINUE THAT PROJECT. It is done.

Based on your experience, estimate what you can do in one month. Then set another date for 30 days away. Build for 30 days. After 30 days, stop.

Again, evaluate what you did in 30 days. Do not continue that project. It is done.

Repeat this for about six months.

Now you will have a solid understanding of what you can do in a given amount of time. Now you can start yet another project. It is okay to plan this one a little bigger, maybe have aspirations for it to be four or six months big, but only plan out for the first month. Plan out that single month knowing what the last six months have taught you, then build for one month. Then build another one-month plan, build it out for a single month. Repeat.

For more than two years I was on a team that was building products for a major online store. Each programming team would launch a new set of online objects about every month, so we would have releases every two weeks. At any given time each programmer would have two projects in various states of completion. One might be in design while another is being polished. One might be in main development while the other is in final verification and testing. Since there was exactly one person of each discipline on the team, and we were responsible for our own estimates, we very quickly learned how much we could accomplish.

After a few months each of us were adept at estimating exactly how long a feature would take. At the end of two years, because were working with a stable code base doing variations on the same task every two weeks, we could typically estimate within a few hours how long a particular task would take.

It is the best way I know to learn how much you can accomplish in a given length of time.

What is your backup plan, in case your project doesn't make any money?

Game development is a risky business investment, and chances are the first few projects you produce won't break even unless you're extremely lucky or a marketing genius. This being the case, do you have something to fall back on financially to keep you afloat during the bad times until you reach the good times?

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For a while the holy grail was get you game on steam but even that is probably not what it used to be. I remember watching the film about indie games and the Super Meat Boy guys were saying most of their sales would come from when they were on the front page of steam after initial release. I get the feel that green light will have broken that now as there is a tsunami of crap on steam now, most indie. So unless you have a unique breakout game it will be hard to rise above the rest

Going off famous two-man indie games according to Wikipedia:

* Braid took about 1 year to reach feature completion, but 3 years until it was released.

* Super Meat Boy took 3 months to prototype and 2 years to release.

So, smaller scope than those?

Yeah. It would have to be smaller. I don't know if I could work on a game for over two years on my own.

If I did try attempt making a game of the same scope as the ones you mentioned, you think people would be willing to buy games in 'episodes'? By this I mean breaking up a larger game into pieces that could be sold as updates. That way, the time between starting and completing something would be significantly reduced.

What is your backup plan, in case your project doesn't make any money?

Game development is a risky business investment, and chances are the first few projects you produce won't break even unless you're extremely lucky or a marketing genius. This being the case, do you have something to fall back on financially to keep you afloat during the bad times until you reach the good times?

I have a decent safety net. Assuming I could complete a game withing 1-2 years,I wouldn't be in the desperate situation you see in some indie game postmortems, even if it doesn't sell.

I get the feel that green light will have broken that now as there is a tsunami of crap on steam now, most indie.

That's not relevant. It doesn't hurt anyone for those extra games to be on there because they're rarely making it to the front page at all.

Also, this makes the fallacious assumption that 'my' work is losing out due to 'other' people's crap; but obviously every developer thinks their work is deserving and the other stuff is not. So now we get a pattern where someone release ssomething that everyone else thinks is crap, but complain that other people's crap is what stopped it selling.

Formerly, only good stuff was on there, so it sold pretty well. Those developers did well because their games were good; not because of the absence of bad games on there.