I reached the boss but couldn't finish, unfortunately the very traditional "go to last checkpoint after dying" mechanic contributes negatively here due to how overly prolonged and uneventful the stages are... 

In terms of feedback I think other commenters (and your replies) pointed out most or all issues already, so I won't go into too much detail, though I think the fact that the entire game is written in C from scratch is an impressive feat. The visuals are also solid, only held back by the stage design and lack of variety in objects. Despite the shortcomings it's pretty awesome that you were able to implement all this in just 10 days

Awesome presentation! Got a lot of R - Type vibes from this!

The visuals are fun! The game progression felt empty-ish to me - I didn't feel I was having progress in the game. Mostly I could just avoid the enemies. It felt polished, the only thing I noticed was the restarting music, but making a loop is not trivial. Small peeve - a spaceship shouldn't be able to "move" back and pick up an item while flying forward!!11 :D And the flight felt "slow" to me, but honestly I have no idea how to make it better without making the game needlessly hard when navigating tight spaces.

Btw, an impressive engineering feat! Extra thanks for sharing the source, it was great checking out a modern game written in C.

The visuals and music were really nice, and it's impressive that you programmed it in C. That being said I felt like the enemy design was a bit lacking. There wasn't that many of them on screen and it was really easy to just fly past them. The only time they felt like somewhat of a threat was right near the end when the corridors got narrower. 

I’m impressed that you wrote this from scratch using C. It’s rare to see things like that in a game jam, but it’s always a commendable accomplishment. The visuals remind me of early 90s shoot-em-ups such as Salamander / Life Force, and they perfectly fit the shrunken-down theme. The ship slid around more than I thought, but it was manageable. Other than that, this is an impressive entry!

Fun and solid gameplay !
Normally I really like the visuals but i played in web version and there is no fullscreen button in that version. That`s why I must play with background image and I felt little bit pain for my eyes because of that :D 
Moving narrow places that was good but action felt like litte bit slower. There is not so much enemies actual difficulty came from narrow places for me. 
Overall it`s a fun game ! Congrats.

This is very impressive for a jam, making a game in C is already impresive for me, I've always used an engine, but doing it from scratch? That's another level. The art is really great, and the level design is very fun, the cover art is also quite good, like one of those retro games from early 90s. I think the controls are a bit too slippery which makes controlling the ship for specially cramped places very difficult, and restarting the level every time is also a bit punishing, especially when the levels are long enough. Those two things are the only things I didn't like, but over all it was a nice experience, especially navigating the levels avoiding the walls, it was very fun.

Its so cool how you made this game from scratch using C! However, I feel like the theme of "Shrink" could've been used more in the game. I know it might have been hard to do something like that tho (no experience with C so idk). It was a nice game nonetheless :D

I like this retro-style shooter games. The parallax effect is very nice too! I really like this game. Good job!

Really striking visuals!

I agree with everyone that there needs to be more to do, though i think the more important critique is in the gameplay. I ran into one of those bone spikes innitially because i mistook it for a background element, and i got a fully upgraded machine gun, only to get a laser powerup that instantly reset me to 1 projectile, the next stage a machine gun powerup dropped ontop of me and it rewrote my laser power up with a basic 1 shot machinegun, which was frustrating. only other thing is that an auto fire or holding down the button would have been nice for the arthritic in the audience.

This has a lot of style! i would love to see more! c:

I am all in for a retro gameplay, it was addictive to play.  initially in the game starting I realised you could basically dodge majority of the enemy, now just my personal choice, but I like having high threat gameplay right from the beginning. But, it was good.