Add docs

Makefile

@@ -2,7 +2,6 @@
 install: go.sum
 	go get -v -t
 
-
 .PHONY: build 
 build: install
 	go build -o sandy 

README.md

@@ -1,5 +1,61 @@
 # Sandy
 
-> A tiny sandbox to run untrusted code.
+> A tiny sandbox to run untrusted code. 🏖️
 
-This is a [WIP]. Bins and docs coming soon.
+Sandy uses Ptrace to hook into READ syscalls, giving you the option to accept or deny syscalls before they are executed.
+
+## Usage
+
+```
+Usage of ./sandy:
+
+  sandy [FLAGS] command
+
+  flags:
+    -h	Print Usage.
+    -n value
+        A glob pattern for automatically blocking file reads.
+    -y value
+        A glob pattern for automatically allowing file reads.
+```
+
+## Use cases
+
+1. You want to install anything
+
+```shell
+> sandy -n "/etc/password.txt" npm i sketchy-module
+
+  BLOCKED READ on /sketchy-module
+```
+
+```shell
+> sandy -n "/etc/password.txt" bash <(curl  https://danger.zone/install.sh)
+
+  BLOCKED READ on /sketchy-module
+```
+
+1. You are interested in what file reads you favourite program makes.
+
+Sure you could use strace, but it references file descriptors sandy makes the this much easier at a glance by printing the absolute path of the fd.
+
+```
+> sandy ls
+Wanting to READ /usr/lib/x86_64-linux-gnu/libselinux.so.1 [y/n]
+```
+
+1. You _don't_ want to buy your friends beer
+
+A friend at work knows that you are security conscious and that you keep a `/free-beer.bounty` file in home directory. With the promise of a round of drinks and office wide humiliation Dave tries to trick you with a malicious script under the guise of being a helpful colleague.
+
+You run there script with sandy and catch him red handed.
+
+```shell
+> sandy -n *.bounty bash ./dickhead-daves-script.sh
+
+  BLOCKED READ on /free-beer.bounty
+```
+
+**NOTE**: It's definitely a better idea to encrypt all your sensitive data, sandy should probably only be used when that is inconvenient or impractical.
+
+**NOTE**: I haven't made any effort for cross-x compatibility so it currently only works on linux. I'd happily accept patches to improve portability.