Cyber//Core; HACK is a game by Lone Colossus Games and was included in the Indie Bundle for Abortion Funds, otherwise it's $4.99. From their page.
Cyber//Core; HACK is a rules-light TTRPG for running quick one-shots or episodic cyberspace hacking missions. In this game, you will play as an elite hacker, taking on only the most difficult and dangerous missions. If it were simple, they wouldn't be hiring you. This also means that you are by no means guaranteed to succeed, and you'll need to use your resources wisely to see each mission through.
Let's get into this ten page PDF.
First thing's first, it's recommended to use this for short games, or even as a drop in rule set for hacking in other games. It can also be run as a 1-GM-1-Player style game, or even GM-less. I wanna keep that in mind because if it's better than Shadowrun's nonsense...
Your core stats are Attack (Brute Force), Defend (Protecting yourself) and Infect (Subtlety). Pretty stock standard, but effective. You start with an attribute set to 1, to 2, and to 3. You will also get to pick a specialization from a list to differentiate you from the other Hackers.
This game uses d4s! 15 goddamn caltrops! This is your default pool of resources to use on a mission. You roll a number of dice equal to your attribute you're using for the check. If you run out of dice, you either suffer some sort of damage (personal/hardware primarily), an d are booted out of the system. You can also lower a stat by 1 for the remainder of the mission to recover some dice. Additionally, before a roll you can Overclock, and increase a stat by 1 for the roll by spending 1 die.
Because it's a D4, you have 4 levels of success: Absolute Failure, Failure, Success, and Critical Success. I'm sure you can imagine what number they relate to on the die. Something neat is that the effect of Failure/Critical Failure has a rider effect depending on the attribute you rolled. If you fail/crit fail on a Defend roll, for example, you lose twice as many dice as you would normally. For Infect/Attack your Detection Level goes up by 1.
Tracking rounds is important here too. You get one Action per round. Attack and Defend actions cost 1 turn, while Infect is 2 turns. Infect Actions appear to mess with difficulty levels, dice pools, and Detection levels. If your Detection level exceeds 2+your Infect, you now have to Defend every turn as security tries to remove you from the server. Getting Detected also raises other hackers' Detection level by 1, due to the host being on higher alert, so you can't quite use a distraction method in cyberspace.
Right off the bat, I like that this puts a timer on your hacking. It gives that sense of urgency that you're racing against the clock.
A lot of actions you can take are Difficulty 0, but some have higher Difficulty. Difficulty subtracts dice from your pool on a roll equal to the Difficulty rating, minimum 0 dice in the pool. You can then Overclock to add a die the pool to roll something.
Each mission is comprised of a cyberspace constructed as "nodes". They compare each node to a room in a dungeon crawl, so they shouldn't be cleared with a single roll. The book mentions several different ways to handle running the Mission, from putting in Turn limits, Turn limits per node, failure limits, and what could be the result of taking too long or spending too much time in a node. Examples given were losing additional Core Dice from the pool, or becoming automatically Detected.
It is a little too vague for how to build a Mission for my tastes, but the game is pretty rules-light and seems to know what it's doing. I like a lot of what it' doing but something feels like it's missing and I can't put my finger on what.