update readme

Author: FalsePattern

README.MD

@@ -1,7 +1,9 @@
 # JFunge
+
 A standard-conforming Funge-98 interpreter.
 
 ### Usage
+
 `jfunge [file] [--3d] [--version] [--license]`
 
 | argument             | usage                                                                                                                           |
@@ -12,17 +14,29 @@ A standard-conforming Funge-98 interpreter.
 | `--license`          | Prints the license of the program.                                                                                              |
 | `--maxiter <number>` | The maximum number of iterations the program can run for. Anything less than 1 will run until the program terminates naturally. |
 
-### References
-- [Esolang wiki article of Funge-98](https://esolangs.org/wiki/Funge-98)
-- [Official funge98 language specification](https://github.com/catseye/Funge-98/blob/master/doc/funge98.markdown)
-- [Mycology Befunge-98 test suite](https://github.com/Deewiant/Mycology)
+### Compatibility
+
+The interpreter's handprint is `0xfa15e9a7` (`-99227225` in decimal), which is a hexadecimal approximation of "`falsepat`" from FalsePattern.
 
-### Currently implemented fingerprints
+The version number given to befunge is `major * 256 * 256 + minor * 256 + patch`, where major, minor, patch are the 3
+primary version numbers in the standard semver format.
+
+The interpreter supports the following Funge-98 specification extensions:
+- The entire Befunge base syntax (tested against Mycology and Mycorand)
+- Buffered IO
+- File IO with `i` and `o`
+- System calls with `=` (paradigm 1, `system()`-like)
+- Concurrency (pseudo-multithreading) with `t`
+- Optional Trefunge mode (experimental)
+
+Additionally, the following fingerprints are currently supported (more to come):
 - [MODE](https://catseye.tc/view/funge-98/library/MODE.markdown)
 - [MODU](https://catseye.tc/view/funge-98/library/MODU.markdown)
 - [NULL](https://catseye.tc/view/funge-98/library/NULL.markdown)
 - [ROMA](https://catseye.tc/view/funge-98/library/ROMA.markdown)
 
-### Additional goals
-- [x] File IO
-- [x] Concurrency
+### References
+
+- [Esolang wiki article of Funge-98](https://esolangs.org/wiki/Funge-98)
+- [Official funge98 language specification](https://github.com/catseye/Funge-98/blob/master/doc/funge98.markdown)
+- [Mycology Befunge-98 test suite](https://github.com/Deewiant/Mycology)