We currently have Mono 4.8 in the ports tree, and Mono 5.2 is available and brings a lot a improvements:
* http://www.mono-project.com/docs/about-mono/releases/5.0.0/
* http://www.mono-project.com/docs/about-mono/releases/5.2.0/
David Naylor (dbn@) has started working on this.
His WIP ports are located in his [GitHub repository](https://github.com/DragonSA/ports) in the [mono-5.2.0.215](https://github.com/DragonSA/ports/tree/mono-5.2.0.215) branch
There is also a [related thread on mono@](https://lists.freebsd.org/pipermail/freebsd-mono/2017-August/002524.html)
```
# git log --oneline master..
1200250 (HEAD -> mono-5.2.0.215, github/mono-5.2.0.215) lang/mono: add acceptance tests back to distinfo
c17fa1a USES=mono: generate package lists by feed
fd71e67 devel/monodevelop: fix nuget fetching by feed
cbba91f lang/mono: automate certificate initialisation
773edb7 devel/monodevelop: fix installation of icons
6a9211d devel/monodevelop: download file required by AzureFunctions
89bfcdd devel/monodevelop: add all feed sources, packages
54ed12c USES=mono: various improvements
faa1e72 devel/msbuild: fix distinfo, python build depends
4be8ba4 lang/fsharp: fix distinfo
04bd243 lang/mono: fix distinfo, update monolite version
3d8841e lang/mono: fix rebasing error, regen distinfo
b032298 devel/monodevelop: initial support for full nuget restore
572b66e Uses=mono: support listing nuget files in a separate file
fb6c349 Uses/mono: add support for multiple sources
362e7d1 devel/msbuild: fix compiling with csc.exe
a334c22 x11-toolkits/gnome-sharp20: update to 2.24.4
086576f x11-toolkits/gtk-sharp20: update to 2.12.45
7d51ef7 lang/mono: increase test coverage
5a934d5 devel/msbuild: add unit test support
961cd5d devel/msbuild: fix changes in NUGET_PACKAGEDIR layout
fff1b7e lang/mono: update to 5.2.0.215
efb2093 lang/mono: update to 5.0.1.1
99972e7 lang/fsharp: update to 4.1.25
07654dc devel/msbuild: fix building of facades
1e190a2 devel/msbuild: fix version number
ef8a88c devel/msbuild: implement installation target
eb126c4 devel/msbuild: switch to self-generated project.lock.json files
00575c4 devel/msbuild: initial building version
```