From mirageos-devel-bounces@lists.xenproject.org Fri May 08 12:49:36 2026 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 08 May 2026 12:49:36 +0000 Received: from list by lists.xenproject.org with outflank-mailman.1303600.1576892 (Exim 4.92) (envelope-from ) id 1wLKdz-0000x0-Nk; Fri, 08 May 2026 12:49:27 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 1303600.1576892; Fri, 08 May 2026 12:49:27 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1wLKdz-0000wt-Kj; Fri, 08 May 2026 12:49:27 +0000 Received: by outflank-mailman (input) for mailman id 1303600; Fri, 08 May 2026 12:49:26 +0000 Received: from mx.expurgate.net ([195.190.135.10]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1wLKdx-0000wl-Iv for mirageos-devel@lists.xenproject.org; Fri, 08 May 2026 12:49:26 +0000 Received: from mx.expurgate.net (helo=localhost) by mx.expurgate.net with esmtp id 1wLKdw-0030F6-Rs for mirageos-devel@lists.xenproject.org; Fri, 08 May 2026 14:49:24 +0200 Received: from [10.42.69.5] (helo=localhost) by localhost with ESMTP (eXpurgate MTA 0.9.1) (envelope-from ) id 69fddbce-e002-0a2a0a5209dd-0a2a450596ac-8 for ; Fri, 08 May 2026 14:49:24 +0200 Received: from [213.73.89.200] (helo=mail.mehnert.org) by tlsNG-c201ff.mxtls.expurgate.net with ESMTPS (eXpurgate 4.56.1) (envelope-from ) id 69fddbd4-aaa8-0a2a45050019-d54959c8bd57-3 for ; Fri, 08 May 2026 14:49:24 +0200 Received: from [192.168.2.120] (unknown [195.52.17.150]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "hannes@mehnert.org", Issuer "mehnert root CA" (not verified)) by mail.mehnert.org (Postfix) with ESMTPS id DADD522A8F for ; Fri, 8 May 2026 14:49:23 +0200 (CEST) X-BeenThere: mirageos-devel@lists.xenproject.org List-Id: Developer list for MirageOS List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: mirageos-devel-bounces@lists.xenproject.org Precedence: list Sender: "MirageOS-devel" Authentication-Results: eu.smtp.expurgate.cloud; dkim=pass header.s=mail header.d=mehnert.org header.i="@mehnert.org" header.h="Date:To:From:Subject" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mehnert.org; s=mail; t=1778244563; bh=EeYwJgV/JkGmjvlX0LPHOv9UO3lU7UXPvEUYUXthSMM=; h=Date:To:From:Subject; b=NgwhIjUokLtRk/71iGrZsbrqt9oCnFqZr19CZ2e/1YgkjXZF4s2y9WEXZShRWW00H OUwDfFL+vURuMvcPd3kgFHvJ3lYfr6a4dsP7vbOcsY8Ik3qv1iGa7q97gLghMUFzKW xyS+6f97wg2m/xgKgNkVe29EPsagxM1uRf/mahMsgrN4KpTTx5tuJIMxEK4OKhRey+ PLkXg8hFqZ16kHSYSDP4jKqATycf/jcBmaWpmlnmu8vt0jd5gyxEZRbvBx1giwoZ7F kDhDEUPGrH+VFkjSbDiFs2luc4QaVNgpBi/dnfVgW0Yxax6PuT03aNNJnQXQ817GEK z1pWNLvHHkd5g== Message-ID: <464de050-20dc-4981-8c4e-e417e8cd6e02@mehnert.org> Date: Fri, 8 May 2026 14:49:23 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: mirageos-devel Content-Language: en-US From: Hannes Mehnert Subject: =?UTF-8?Q?Mirage_4=2E11=2E0_released!_With_built-in_support_for_?= =?UTF-8?Q?=C2=B5TCP=2C_and_DNS/log/everything_configuration_via_DHCP?= Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-purgate-ID: tlsNG-c201ff/1778244564-D9772443-43F38727/0/0 X-purgate-type: clean X-purgate-size: 3512 Dear MirageOS hackers, after the longer 4.10 line of mirage, we just released mirage 4.11.0. To summarize the changes within the last year (4.10 released September 2025): - µTCP can be used when `--utcp` is provided at configuration time (per network device, i.e. --utcp, --management-utcp, --private-utcp) https://github.com/mirage/mirage/pull/1636 - DHCP is now enabled by default, and is able to set the DNS server in the DNS stack (and of course other DHCP configuration options, not only IP address and routers) https://github.com/mirage/mirage/pull/1628 - each unikernel accepts a `--name` argument (available via Mirage_runtime.name ()) https://github.com/mirage/mirage/pull/1611; this is sent as requested Hostname in DHCP https://github.com/mirage/mirage/pull/1632 - unikraft target https://github.com/mirage/mirage/pull/1607 - there's a ~local_libs argument to Mirage.main to use local dune libs (https://github.com/mirage/mirage/pull/1609, see mirage-skeleton example https://github.com/mirage/mirage-skeleton/tree/main/tutorial/local-library) - Makefile now includes the output file extensions https://github.com/mirage/mirage/pull/1619 - breaking: --dhcp=true/false is now a flag --no-dhcp https://github.com/mirage/mirage/pull/1636 - ?tcp, ?dhcp_key, ?net_key have been removed from Mirage.*stack* https://github.com/mirage/mirage/pull/1636 - boot arguments use "-" instead of "_" (i.e. "--dns-servers") https://github.com/mirage/mirage/pull/1638 - various cleanups and fixes https://github.com/mirage/mirage/pull/1612, https://github.com/mirage/mirage/pull/1615, https://github.com/mirage/mirage/pull/1614, https://github.com/mirage/mirage/pull/1613, https://github.com/mirage/mirage/pull/1620, https://github.com/mirage/mirage/pull/1622, https://github.com/mirage/mirage/pull/1623, https://github.com/mirage/mirage/pull/1625, https://github.com/mirage/mirage/pull/1628, https://github.com/mirage/mirage/pull/1635 There may be some further things that broke. Please let us know if you're stuck upgrading your unikernel. ## µTCP µTCP (https://github.com/robur-coop/utcp) is a TCP stack developed from scratch based on the HOL4 model (https://www.cl.cam.ac.uk/~pes20/Netsem/). The stack is purely in OCaml and value-passing style (sans-IO, as pioneered by OCaml-TLS [David Kaloper Meršinjak]). Already now we have another backend for µTCP that doesn't rely on lwt - something very hard to do with the existing "old" TCP stack from https://github.com/mirage/mirage-tcpip (src/tcp). There is still ongoing work on µTCP, but we are also testing it since more than a year on some production systems on the Internet with good results. It is smaller, allocates less, and (hopefully) easier to maintain than the old TCP stack. ## DHCP For deployments, we now fully support DHCP, such that configuration parameters (syslog sink, metrics, DNS server, ...) can be taken from DHCP. This required some restructuring of the DHCP stack, as well as some work on the mirage tool to provide DHCP configuration information to other subsystems (without them having to depend on the DHCP package). If you're interested in further details, don't hesitate to reach out via mail (on this list, or privately). We're in full momentum re-deploying our unikernel hive, removing the plasters we needed before we had these opportunities. Happy victory day (bomber harris do it again), Hannes From mirageos-devel-bounces@lists.xenproject.org Fri May 08 12:58:03 2026 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 08 May 2026 12:58:03 +0000 Received: from list by lists.xenproject.org with outflank-mailman.1303608.1576897 (Exim 4.92) (envelope-from ) id 1wLKmG-0002Q9-CD; Fri, 08 May 2026 12:58:00 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 1303608.1576897; Fri, 08 May 2026 12:58:00 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1wLKmG-0002Q2-9h; Fri, 08 May 2026 12:58:00 +0000 Received: by outflank-mailman (input) for mailman id 1303608; Fri, 08 May 2026 12:57:58 +0000 Received: from mx.expurgate.net ([195.190.135.10]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1wLKmE-0002Pw-7L for mirageos-devel@lists.xenproject.org; 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boundary="Apple-Mail=_CF76B1FD-1490-4E6C-A191-7FF487D3799C" Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.500.181\)) Subject: =?utf-8?Q?Re=3A_Mirage_4=2E11=2E0_released!_With_built-in_support?= =?utf-8?Q?_for_=C2=B5TCP=2C_and_DNS/log/everything_configuration_via_DHCP?= Date: Fri, 8 May 2026 13:57:40 +0100 In-Reply-To: <464de050-20dc-4981-8c4e-e417e8cd6e02@mehnert.org> Cc: mirageos-devel To: Hannes Mehnert References: <464de050-20dc-4981-8c4e-e417e8cd6e02@mehnert.org> X-Mailer: Apple Mail (2.3864.500.181) X-purgate-ID: tlsNG-33051d/1778245076-41F90938-D540EADE/0/0 X-purgate-type: clean X-purgate-size: 6954 --Apple-Mail=_CF76B1FD-1490-4E6C-A191-7FF487D3799C Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 > On May 8, 2026, at 1:49=E2=80=AFPM, Hannes Mehnert = wrote: >=20 > =C2=B5TCP (https://github.com/robur-coop/utcp) is a TCP stack = developed from scratch based on the HOL4 model = (https://www.cl.cam.ac.uk/~pes20/Netsem/). The stack is purely in OCaml = and value-passing style (sans-IO, as pioneered by OCaml-TLS [David = Kaloper Mer=C5=A1injak]). Already now we have another backend for =C2=B5TC= P that doesn't rely on lwt - something very hard to do with the existing = "old" TCP stack from https://github.com/mirage/mirage-tcpip (src/tcp). >=20 > There is still ongoing work on =C2=B5TCP, but we are also testing it = since more than a year on some production systems on the Internet with = good results. It is smaller, allocates less, and (hopefully) easier to = maintain than the old TCP stack. Great to see an alternative! How's the performance compared to = mirage-tcpip? Congestion control was very complex to stabilise in = mirage-tcpip back in the day. best, Anil= --Apple-Mail=_CF76B1FD-1490-4E6C-A191-7FF487D3799C Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8
On = May 8, 2026, at 1:49=E2=80=AFPM, Hannes Mehnert = <hannes@mehnert.org> wrote:

=C2=B5TCP (https://github.com/robur-coop/utcp) is a TCP stack developed from scratch = based on the HOL4 model (https://www.cl.cam.ac.uk/~pes20/Netsem/). The stack is purely in OCaml and = value-passing style (sans-IO, as pioneered by OCaml-TLS [David Kaloper = Mer=C5=A1injak]). Already now we have another backend for =C2=B5TCP that = doesn't rely on lwt - something very hard to do with the existing "old" = TCP stack from https://github.com/mirage/mirage-tcpip (src/tcp).

There is still ongoing work on =C2=B5TCP, = but we are also testing it since more than a year on some production = systems on the Internet with good results. It is smaller, allocates = less, and (hopefully) easier to maintain than the old TCP = stack.

Great to see an = alternative! How's the performance compared to mirage-tcpip? Congestion = control was very complex to stabilise in mirage-tcpip back in the = day.

best,
Anil
= --Apple-Mail=_CF76B1FD-1490-4E6C-A191-7FF487D3799C--