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btreut
a2
Modula-22016–2026
btreut / a2

a2

Active Oberon System (AOS), aka A2, and Bluebottle OS

5Distinct people
13Mentions
0Explicit recommenders
96GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Active Oberon System (AOS), aka A2, and Bluebottle OS

GitHub

Where it is used

No documented product use has been verified yet.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 9:28:18 AM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year13 dated mentions

Observed mentions: 2016-03-19 20:38:14 UTC to 2026-08-09 18:33:56 UTC.

01232016-01-01 00:00:00 UTC to 2017-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments20162017-01-01 00:00:00 UTC to 2018-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments20212022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2026-01-01 00:00:00 UTC to 2027-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments. Incomplete calendar period.2026*

* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20162016-01-01 00:00:00 UTC2017-01-01 00:00:00 UTC101
20172017-01-01 00:00:00 UTC2018-01-01 00:00:00 UTC202
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC303
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC000
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC202
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC000
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC303
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC101
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC000
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC000
2026 (partial)2026-01-01 00:00:00 UTC2027-01-01 00:00:00 UTC101

What Hacker News says

2 sources
It's been done in the past. OS's come to dominate mostly for marketing rather than technical reasons. Much like startups. Integration with legacy systems and rapid development increase chance they'll get uptake. The existing stuff is mostly C, C++, etc. So, the new stuff that dominates tends to reuse that. Redoing it all in a safe language will be a lot of work. That's why high-assurance security has focused on redoing the smallest, most-trusted parts of the stack or working on transformations of legacy code like Softbound+CETS or CHERI CPU that address root problems. Although I doubt we'll see a big one, there's already smaller projects that do useful stuff with safer languages. ExpressOS comes to mind given the kernel is C# and Dafny running Android apps that are Java. The L4 kernel and Linux remain in the system with L4 replaceable by
Read the rest
safe stuff like Muen in SPARK language. Replacing Linux will be a lot harder. ;) However, if wanting mobile or other apps that aren't Android compatible, one might be able to use work like Redox, JX, or Oberon to eliminate unsafe language entirely. https://haohuim.appspot.com/static/pubs/expressos-asplos13-s... Another in alternative OS's is A2 Bluebottle from Wirth's people at ETH written in an Oberon dialect. Main Oberon OS is designed for simplicity and teaching. A2 is a batteries-included OS with a GUI designed to be useful. When I tried it, it ran snappy fast with networking, editor, compiler, and so on. Very minimal given only a few students worked on it but it is usable and extendable. Below was first link I found in Google so I haven't vetted it. https://github.com/Ignat99/a2 Redox OS in Rust can do a lot currently. They plan to expand it more. Already has a GUI, shell, networking, and the standard library of Rust. http://redox-os.org/
In A survey of BSD kernel vulnerabilities [pdf]

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