Project Oberon,<p><a href="https://www.projectoberon.net" rel="nofollow">https://www.projectoberon.net</a><p>The evolution of Oberon based OSes,<p>Ethos, <a href="https://www.research-collection.ethz.ch/handle/20.500.11850/140827" rel="nofollow">https://www.research-collection.ethz.ch/handle/20.500.11850/...</a><p>Active Oberon which is the Oberon variant I prefer,<p><a href="https://en.wikipedia.org/wiki/A2_(operating_system)" rel="nofollow">https://en.wikipedia.org/wiki/A2_(operating_system)</a>
<a href="https://en.wikipedia.org/wiki/Active_Oberon" rel="nofollow">https://en.wikipedia.org/wiki/Active_Oberon</a>
<a href="https://gitlab.inf.ethz.ch/felixf/oberon" rel="nofollow">https://gitlab.inf.ethz.ch/felixf/oberon</a><p>Some screenshots at my article, take it while the site still exists,<p><a href="https://www.progtools.org/article.php?name=oberon&section=compilers&type=tutorial" rel="nofollow">https://www.progtools.org/article.php?name=oberon&section=co...</a><p>SPIN, done in Modula-3<p><a href="https://www-spin.cs.washington.edu/external/overview.html" rel="nofollow">https://www-spin.cs.washington.edu/external/overview.html</a><p>Singularity,<p><a href="https://www.microsoft.com/en-us/research/project/singularity/?from=https://research.microsoft.com/en-us/projects/singularity" rel="nofollow">https://www.microsoft.com/en-us/research/project/singularity...</a><p><a href="https://github.com/lastweek/source-singularity" rel="nofollow">https://github.com/lastweek/source-singularity</a><p>Midori,<p>although no source code, the blog posts, existing talks and internal session at Microsof do provide some nice overview,<p><a href="https://joeduffyblog.com/2015/11/03/blogging-about-midori/" rel="nofollow">https://joeduffyblog.com/2015/11/03/blogging-about-midori/</a><p>"The Midori Operating System Overview"<p><a href="https://www.youtube.com/watch?v=37WgsoZpf3k" rel="nofollow">https://www.youtube.com/watch?v=37WgsoZpf3k</a><p>"Safe Systems Programming in C# and .NET"<p><a href="https://www.infoq.com/presentations/csharp-systems-programming/" rel="nofollow">https://www.infoq.com/presentations/csharp-systems-programmi...</a><p>"Safe Systems Software and the Future of Computing"<p><a href="https://www.youtube.com/watch?v=CuD7SCqHB7k" rel="nofollow">https://www.youtube.com/watch?v=CuD7SCqHB7k</a><p>Xerox PARC Mesa, used on the Xerox Star OS<p><a href="https://en.wikipedia.org/wiki/Mesa_(programming_language)" rel="nofollow">https://en.wikipedia.org/wiki/Mesa_(programming_language)</a>
<a href="https://en.wikipedia.org/wiki/Xerox_Star" rel="nofollow">https://en.wikipedia.org/wiki/Xerox_Star</a><p><a href="https://computerhistory.org/blog/xerox-alto-source-code/" rel="nofollow">https://computerhistory.org/blog/xerox-alto-source-code/</a><p>Xerox PARC Cedar, used on Dorado platforms<p><a href="http://toastytech.com/guis/cedar.html" rel="nofollow">http://toastytech.com/guis/cedar.html</a><p><a href="https://www.youtube.com/watch?v=z_dt7NG38V4" rel="nofollow">https://www.youtube.com/watch?v=z_dt7NG38V4</a><p><a href="https://bitsavers.trailing-edge.com/pdf/xerox/parc/cedar/The_Cedar_Manual_Version_4.2_Jun83.pdf" rel="nofollow">https://bitsavers.trailing-edge.com/pdf/xerox/parc/cedar/The...</a><p><a href="https://worrydream.com/refs/Swineheart_1986_-_A_Structural_View_of_the_Cedar_Programming_Environment.pdf" rel="nofollow">https://worrydream.com/refs/Swineheart_1986_-_A_Structural_V...</a><p><a href="http://www.bitsavers.org/pdf/xerox/parc/techReports/CSL-83-11_The_Cedar_Programming_Environment_A_Midterm_Report_and_Examination.pdf" rel="nofollow">http://www.bitsavers.org/pdf/xerox/parc/techReports/CSL-83-1...</a><p>Xerox PARC Smalltalk,<p>original documentation can be taken from <a href="http://stephane.ducasse.free.fr/FreeBooks.html" rel="nofollow">http://stephane.ducasse.free.fr/FreeBooks.html</a><p>- Smalltalk-80, Bits of History, Words of Advice<p>- Smalltalk-80: The Language and its Implementation<p>- Smalltalk-80, The Interactive Programming Environment<p>Squeak and Pharos linage,<p><a href="https://squeak.org/" rel="nofollow">https://squeak.org/</a><p><a href="https://pharo.org/" rel="nofollow">https://pharo.org/</a><p>Xerox PARC Interlisp-D, with Medley<p><a href="https://dl.acm.org/doi/pdf/10.1145/1056743.1056745" rel="nofollow">https://dl.acm.org/doi/pdf/10.1145/1056743.1056745</a><p><a href="https://interlisp.org/" rel="nofollow">https://interlisp.org/</a><p>House, written in Haskell<p><a href="https://programatica.cs.pdx.edu/House/" rel="nofollow">https://programatica.cs.pdx.edu/House/</a><p>MirageOS, written in OCaml, partially used by Docker (TCP/IP stack), and Xen Hypervisor<p><a href="https://mirage.io/" rel="nofollow">https://mirage.io/</a><p><a href="https://mirage.io/blog/2022-04-06.vpnkit" rel="nofollow">https://mirage.io/blog/2022-04-06.vpnkit</a><p><a href="https://xenproject.org/projects/mirage-os/" rel="nofollow">https://xenproject.org/projects/mirage-os/</a><p>AmigaOS,<p><a href="http://toastytech.com/guis/indexamiga.html" rel="nofollow">http://toastytech.com/guis/indexamiga.html</a><p><a href="https://en.wikipedia.org/wiki/Amiga" rel="nofollow">https://en.wikipedia.org/wiki/Amiga</a><p><a href="https://www.amigaos.net/content/1/features" rel="nofollow">https://www.amigaos.net/content/1/features</a><p><a href="https://aros.sourceforge.io/" rel="nofollow">https://aros.sourceforge.io/</a><p>Solo in Concurrent Pascal,<p>The solo operating system: A concurrent pascal program<p><a href="https://stacks.stanford.edu/file/druid:vb843ff4581/vb843ff4581.pdf" rel="nofollow">https://stacks.stanford.edu/file/druid:vb843ff4581/vb843ff45...</a><p>Lillith in Modula-2<p><a href="https://bitsavers.org/pdf/eth/lilith/ETH7646_Lilith_A_Workstation_Computer_For_Modula-2_1984.pdf" rel="nofollow">https://bitsavers.org/pdf/eth/lilith/ETH7646_Lilith_A_Workst...</a><p><a href="https://www.modula2.org/modula2-history.php" rel="nofollow">https://www.modula2.org/modula2-history.php</a><p>Now go out and explore, UNIX is not the be all, end all of how an OS is supposed to be, neither is C the ultimate systems programming language.