# # Links to pages I've considered interesting at some time # # This file is intentionally maintained in a machine-readable form, but # data format is not guaranteed to remain stable over time # - period: 2024-06 links: - title: TechInfoDepot Wiki (hardware specs for wireless routers) url: https://techinfodepot.shoutwiki.com/wiki/Main_Page description: |- This knowledge base complements [OpenWRT docs](https://openwrt.org/docs/start) with a lot of hardware specific information. It is a fork of WikiDevi (shut down in 2019), similar to: - [Wireless CAT Wiki](https://wikidevi.wi-cat.ru/Main_Page) - [DeviWiki](https://deviwiki.com/wiki/) - title: Fight understanding decay with a rich Incident Summary by: Dan Slimmon url: https://blog.danslimmon.com/2024/06/14/fight-knowledge-decay-with-a-rich-incident-summary/ description: |- Role of _scribe_ during incident response is not only to keep track of _incident timeline_ but also to maintain an _incident summary_ for when new responders join the effort. - title: What is PID 0? by: Dave Anderson url: https://blog.dave.tf/post/linux-pid0/ description: |- > Unix PIDs do start at 0! PID 0 just isn’t shown to userspace through > traditional APIs. PID 0 starts the kernel, then retires to a quiet life > of helping a bit with process scheduling and power management. Also the > entire web is mostly wrong about PID 0, because of one sentence on > Wikipedia from 16 years ago. - title: The curious case of stalled squashfs reads by: Chris Down url: https://chrisdown.name/2018/04/17/kernel-adventures-the-curious-case-of-squashfs-stalls.html description: |- Facebook SRE debugs stalled squashfs reads down to a suboptimal kernel configuration. These days CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU is enabled by default in Debian, so the problem should not reoccur. In the last part of the article author recommends using btrfs for blockdevs with transparent compression in production environment. - period: 2024-05 links: - title: > "Is This Project Still Maintained?" by: Matt Palmer url: https://www.hezmatt.org/~mpalmer/blog/2024/05/14/is-this-project-still-maintained.html description: |- Some thoughts on maintainer responsibilities, user entitlement and personal projects. Also contains a draft of "The Open Source Maintainer's Manifesto" - title: IPv6 Prefix Lengths url: https://www.potaroo.net/ispcol/2024-04/ipv6-prefixes.html description: |- > I’m left with the observation that IPv6 is not in fact a 128-bit > address protocol in the same way as IPv4 is a 32-bit address protocol. > It’s a “64-bits plus a few extra interface identifier bits” address > protocol. - period: 2024-04 links: - title: DDC OLED (Driving OLED display via HDMI I2C pins) url: https://mitxela.com/projects/ddc-oled description: |- HDMI cables contain an i2c bus (yay backwards compatibility) which can be (ab)used for some fun projects. [Changing EDID serial] may have real world [applications], may be some devices for that already [exist]? [Changing EDID serial]: https://forum.espruino.com/conversations/325555/ [applications]: https://notes.alinpanaitiu.com/Weird%20monitor%20bugs [exist]: https://www.aten.com/global/en/products/professional-audiovideo/video-converters/vc081a/ - title: 'Passkeys: A Shattered Dream' by: William Brown url: https://fy.blackhats.net.au/blog/2024-04-26-passkeys-a-shattered-dream/ description: |- An apt description of why current hype around passkeys makes me uneasy - title: Linux Security Hardening and Other Tweaks by: blakkheim url: https://vez.mrsk.me/linux-hardening.html description: |- Many security-related sysctl options. Should probably consider adopting most of those after a review. - title: My deployment platform is a shell script by: Jes Olson url: https://j3s.sh/thought/my-deployment-platform-is-a-shell-script.html description: |- Not that I agree with everything the author says, but saving this anyways. Author is an interesting person with a good writing style. Will read more. Jes Olson is also involved in running a [hackerspace](https://layerze.ro/) and a [computer club](https://cyberia.club/) in Minneapolis. - period: 2024-03 links: - title: Timeline of the xz open source attack by: Russ Cox url: https://research.swtch.com/xz-timeline description: |- Over a period of over two years, an attacker using the name “Jia Tan” worked as a diligent, effective contributor to the xz compression library, eventually being granted commit access and maintainership. Using that access, they installed a very subtle, carefully hidden backdoor into liblzma, a part of xz that also happens to be a dependency of OpenSSH sshd on Debian, Ubuntu, Fedora, and other systemd-based Linux systems - title: Corel Netwinder - Linux ARM PC from 1999 url: http://www.netwinder.org/about.html description: |- An interesting relic of turn-of-millenium Internet describing an interesting piece of hardware. Some old user pages are still online, [~tinymoth](https://netwinder.osuosl.org/users/t/tinymoth/public_html/) contains photos of motherboard and chip identifiers. - period: 2024-02 links: - title: The power of two random choices by: Marc Brooker url: https://brooker.co.za/blog/2012/01/17/two-random.html description: |- A simple load balancing strategy that is surprisingly effective even when operating on cached data - title: How Doom didn't kill the Amiga by: Carl Svensson url: https://www.datagubbe.se/afb/ description: A detailed account of the rise and fall of an Amiga zealot - period: 2024-01 links: - title: What is the difference between /dev/ttyUSB and /dev/ttyACM? by: Samuel Tardieu url: https://rfc1149.net/blog/2013/03/05/what-is-the-difference-between-devttyusbx-and-devttyacmx/ description: |- Microcontroller based USB devices often present themselves as a modem instead of using a proper USB-to-UART device signature. Looks like CDC (Communications Device Class) is simpler to implement in firmware. Here is a [relevant comment] regarding CDC-ACM implementation [relevant comment]: https://old.reddit.com/r/linux/comments/11y07qn/w/jd81taw/ - period: 2023-12 links: - title: Paged Out! (magazine) url: https://pagedout.institute/ description: |- Web zine with one-page articles about programming, hacking, security, demoscene, etc. - title: Solving the Looming Developer Liability Problem by: James Bottomley url: https://blog.hansenpartnership.com/solving-the-looming-developer-liability-problem/ description: |- Current _no warranty_ clauses may not be enough to limit developer liability under new legislation, for example EU Cyber Resilience Act. New clauses may be required to add indemnification to existing licenses. - period: 2023-11 links: - title: How to build a plugin system on the web and also sleep well at night by: Figma url: https://www.figma.com/blog/how-we-built-the-figma-plugin-system/ description: |- Running untrusted and potentially unsafe code in your application is difficult. Figma considered multiple options and went with Javascript Realms Shim. They have had to [migrate] to a separate JS interpreter compiled to WASM after [vulnerabilities] have been discovered in Realms Shim. [vulnerabilities]: https://agoric.com/blog/technology/realms-shim-security-updates [migrate]: https://www.figma.com/blog/an-update-on-plugin-security/ - period: 2023-10 links: - title: getaddrinfo() on glibc calls getenv(), oh boy by: Rachel Kroll url: https://rachelbythebay.com/w/2023/10/16/env/ description: |- This affects Go when it's used with CGO_ENABLED (`netdns=cgo`), i.e. by default. - title: Stealing power out of PC RS-232 port by: Tomi Engdahl url: https://www.epanorama.net/circuits/rspower.html description: |- An awful awful idea to use RS-232 signal lines as power source. I love it! Turns out you can steal 3-5mA per line (times three for DTR, RTS, TD) before triggering short circuit protection - which gives you an ample power budget of 40-90mW! - title: Finding the Best Block Filesystem by: Michael Opdenacker url: https://bootlin.com/pub/conferences/2023/eoss/opdenacker-finding-best-block-filesystem/opdenacker-finding-best-block-filesystem.pdf description: |- Comparison of mainline Linux filesystems for use as rootfs in embedded devices. EROFS provides some extra read performance but the advantage is not significant. Squashfs still wins on image size, especially with zstd compression. - period: 2023-09 links: - title: Useful settings for grub on Debian by: Ansgar Wiechers url: https://www.planetcobalt.net/sdb/grub_settings.shtml description: |- `panic=2` in kernel cmdline will trigger automatic reboot after kernel panic. Useful for one-off kernel tests and for unattended machines - title: Protecting SSH authentication with TPM 2.0 by: Nicolas Iooss url: https://www.sstic.org/media/SSTIC2021/SSTIC-actes/protecting_ssh_authentication_with_tpm_20/SSTIC2021-Article-protecting_ssh_authentication_with_tpm_20-iooss.pdf description: |- Page 19: > This confirms that tpm2-pkcs11’s database contains an encrypted version > of the private key, stored in attribute CKA_TPM2_PRIV_BLOB of the > PKCS#11 object associated with the private key. This attribute is > encrypted using the seedValue of the used SRK, which is a secret > supposed to never leave the TPM. Therefore this analysis also confirms > that only the TPM itself can decrypt this attribute. See also: [slides](https://www.barbhack.fr/2021/slides/barbhack2021_tpm_auth.pdf) - period: 2023-08 links: - title: Using Ed25519 signing keys for encryption by: Filippo Valsorda url: https://words.filippo.io/using-ed25519-keys-for-encryption/ description: Ed25519 keys may be converted to X25519 keys to be used for encryption. Unfortunately, this requires access to raw private key material and will not work for keys stored in ssh-agent - period: 2023-07 links: - title: Cap'n Proto - cerealization protocol url: https://capnproto.org/ description: |- Binary serialization protocol used extensively at Cloudflare. Is faster and feels cleaner than protobufs. - title: Understanding SSH url: https://containerssh.io/development/containerssh/ssh/ description: |- An introductory overview of SSH protocol. Helpful if you're implementing your own SSH server - period: 2023-05 links: - title: The TTY demystified by: Linus Åkesson url: https://www.linusakesson.net/programming/tty/ description: |- Good introduction into the world of ttys. Explains the relationship between ttys, ptys, line discipline and mixes in a sidebar on Unix signals. - period: 2023-03 links: - title: Hexagonal Grids - Cube Coordinates url: https://www.redblobgames.com/grids/hexagons/#coordinates-cube description: |- How to reason about hexagonal tiles when programming - period: 2023-01 links: - title: Golang is evil on shitty networks url: https://withinboredom.info/blog/2022/12/29/golang-is-evil-on-shitty-networks/ description: |- With a folow up: [The Cargo Cult of TCP_NODELAY](https://withinboredom.info/blog/2023/01/03/the-cargo-cult-of-tcp_nodelay-when-to-use-it/) This article notices and explains an opinionated Golang's default of setting TCP_NODELAY on all TCP sockets. It's used to improve throughput over datacenter-grade links (Ethernet) but may result in poor performance on unreliable networks (WiFi, mobile). Userspace IO buffering may help to work around this problem because raw socket is not easily exposed in Golang (to revert this setting in case it's required). - period: 2022-12 links: - title: Go is not an easy language url: https://www.arp242.net/go-easy.html by: Martin Tournoij description: |- Even though Go is _simple_, often it is not _easy_ - title: Your problem with Vim is that you don't grok vi url: https://stackoverflow.com/a/1220118 description: |- A StackOverflow answer that could have been a long blog post. Good explanation of some vi intricacies I didn't understand before. - period: 2022-11 links: - title: What Colour are your bits? url: https://ansuz.sooke.bc.ca/entry/23 description: |- Information (bits) may have some properties that are not possible to calculate from data alone. Does this transmission violate copyright? Is this file infected by a virus? Is this number random? - title: Everything I wish I knew when learning C url: https://tmewett.com/c-tips/ description: |- This is why I don't write C - title: Everything you should know about certificates and PKI but are too afraid to ask url: https://smallstep.com/blog/everything-pki/ description: |- Ground up explanation of X.509 public key infrastructure. SSH and PGP PKI's are mentioned but not described. - title: Mataroa Blog Collection url: https://collection.mataroa.blog/ description: |- Curated list of personal blogs. I've found some blogs there with just two or three entries each, all of them interesting. That's two or three entries better that an average blog (in my experience). - title: The Great Noun List by: Desi Quintans url: http://www.desiquintans.com/nounlist description: |- List of 6700+ most popular English nouns. Useful for all kinds of things. Dedicated to public domain, no usage restrictions, no attribution required. - title: >- SSH: Uniqueness of User Certificates Serial Numbers url: https://yaobinwen.github.io/2021/03/26/SSH-X509-cert-serial-numbers.html description: |- Uniqueness of SSH user certificate serial numbers is left up to issuer to implement. For a low volume CA golang's UnixNano() seems not bad. - period: 2022-10 links: - title: Next GitLab Runner Auto-scaling Architecture (RFC) url: https://docs.gitlab.com/ee/architecture/blueprints/runner_scaling/ description: |- At this moment one of our core products - GitLab Runner - and one of its most important features - ability to auto-scale job execution environments - depends on an external product that is abandoned. - title: Bottom-up eBPF url: https://medium.com/@phylake/bottom-up-ebpf-d7ca9cbe8321 description: |- This article shows where `SEC` macro comes from but I'm still not sure if similar `__section` macro is its accepted successor. It's certainly seen more often in the wild. - title: Custom BPF firewalls for systemd services url: https://kailueke.gitlab.io/systemd-custom-bpf-firewall/ description: |- Unfortunately, `net_cls` was deprecated and dropped in cgroups v2, so writing custom eBPF programs appears to be the only way to achieve per-unit firewalling with systemd. See also: - [Similar thought process in Gnome bug tracker](https://gitlab.gnome.org/GNOME/gnome-software/-/issues/1038) - [Writing cgroup/skb BPF program in Rust](https://aya-rs.dev/book/programs/cgroup-skb/) - [Well-commented example of cgroup/skb program](https://github.com/mk-fg/fgtk/blob/master/bpf/cgroup-skb.nonet.c) - [Using Cilium libraries to interact with eBPF program from Go](https://nfil.dev/coding/security/ebpf-firewall-with-cgroups/) - [Where packet mark is stored in sk_buff](https://unix.stackexchange.com/a/467164/5255) - [eBPF __sk_buff is not kernel's sk_buff](https://medium.com/@c0ngwang/understanding-struct-sk-buff-730cf847a722) - man 7 bpf-helpers -> bpf_setsockopt -> SO_MARK; man 7 socket -> SO_MARK - ['uknown function' when loading a BPF program may mean that helper is just not allowed](https://stackoverflow.com/a/62173263/3275560) - period: 2022-09 links: - title: How to create an SSH certificate authority url: https://jameshfisher.com/2018/03/16/how-to-create-an-ssh-certificate-authority/ by: Jim Fisher description: |- SSH certificates and surrounding infrastructure are tough to get a handle on. Especially these days when every article tries to push their _access plane single sign-on RBAC solution._ Jim Fisher's explanation just clicked for me. SSH cert authority is simply another SSH key pair. - title: Signing arbitrary data with SSH keys url: https://www.agwa.name/blog/post/ssh_signatures description: |- Using ssh-keygen instead of PGP to sign arbitrary data is easier and (seems to be) as safe. Namespaces are a neat feature that prevents signature reuse across protocols. - title: Create ED25519 certificates for TLS with OpenSSL url: https://blog.pinterjann.is/ed25519-certificates.html description: |- It is possible to sign X.509 certificates (HTTPS / TLS) with a ED25519 key even though no root CA does that. Useful for selfsigned certs though - title: Exfiltration by encoding data in pixel colour values url: https://www.pentestpartners.com/security-blog/exfiltration-by-encoding-data-in-pixel-colour-values/ description: |- I've had the same idea last night. Unsurprisingly, someone else had thought of it 5 years ago and had already coded a proof-of-concept. It's a shame that GitHub repo is just a ZIP dump. *Note*: RDP is not a pixel perfect protocol, it modifies color values in a way not perceptible for humans. This makes theoretical density of 24 bits per pixel impossible. Article author had settled for mere 3 bits per pixel (with a large safety margin). Author estimates that 15 bits per pixel should be achievable on a good connection - title: Immutable Linux OS with a hermetic /usr partition url: https://0pointer.net/blog/fitting-everything-together.html by: Lennart Poettering description: |- Thoughts on how to build an immutable Linux OS with automated A/B rootfs image upgrades. Notable mentions: - [mkosi](https://0pointer.net/blog/mkosi-a-tool-for-generating-os-images.html) - [systemd-nspawn](https://www.freedesktop.org/software/systemd/man/systemd-nspawn.html) - period: 2022-08 links: - title: DuckCorp - a non-profit Magical Organization url: https://users.duckcorp.org/index.php/A_bit_of_History description: |- I always admire (and envy) friend groups which set out to build something and then _actually_ build something. DuckCorp is an endearing example of such. Started at a student dorm and still alive and evolving 20+ years later, they run some IT infrastructure and provide software and services to members. - title: Johnny.Decimal system url: https://johnnydecimal.com/ description: |- A personal system for information/knowledge/data classification and management. Applicable to file system hierarchy, emails, note taking apps and even to IRC logs. I doubt I'll ever implement something like this for myself, but it never hurts to have an option. - title: Contributor-maintainer-project fallacy url: https://www.reddit.com/r/opensource/comments/wxozko/comment/ilslpdb/ description: |- That's where the contributor-maintainer-project rhetoric comes in. Calling the key people in this scenario (you, and that other person who is using your code) "maintainer" and "contributor", and the software you wrote a "project", is highly suggestive; it implies a few things that, while not true, create big expectations - title: How NAT traversal works url: https://tailscale.com/blog/how-nat-traversal-works/ by: Tailscale description: |- A systematic review of firewall hole punching (with and without NAT and/or CGNAT in between). Tailscale uses that to build their VPN mesh but the article is applicable to any P2P communication over UDP. - title: ToolJet - low code CRUD app builder url: https://docs.tooljet.com/docs/ description: |- ToolJet (AGPLv3) allows hand-crafting SQL queries and applying Javascript transformations to process the data. That's a nice feature many competitors are lacking. I did not try ToolJet yet. Bookmarking to return to this later. Also consider: - [Baserow](https://baserow.io/) (MIT Expat + EULA for some components) - [AppSmith](https://www.appsmith.com/) (Apache-2.0) - [Budibase](https://budibase.com/) (GPLv3 mostly) - [Lowdefy](https://github.com/lowdefy/lowdefy) (Apache-2.0) - period: 2022-07 links: - title: USB WiFi adapters in Linux url: https://github.com/morrownr/USB-WiFi/blob/main/home/USB_WiFi_Chipsets.md description: |- To summarize: Drivers are a big problem. In-tree kernel support is even bigger problem. 2.4GHz recommendation seems to be Ralink rt5370, for 5GHz there are reports of success with mt7612u, mt7610u Beware: mt7601u on Linux does not support AP mode See also: - title: On github as a social network by: Eric Bower url: https://erock.io/2022/06/03/github-as-social-network.html description: |- Why do I get so excited when I receive stars on my projects hosted on github? I am constantly trying to come up with new projects to build, but do I actually want to build them? Or do I just want social currency? I’m not sure I can tell the difference anymore. Github isn’t just a code repository, it’s a social networking site. - title: Software freedom isn’t about licenses – it’s about power by: Alyssa Rosenzweig url: https://rosenzweig.io/blog/software-freedom-isnt-about-licenses-its-about-power.html description: |- Licensing does matter; user autonomy is lost with subscription models, revocable licenses, binary-only software, and onerous legal clauses. Yet these issues pertinent to desktop software do not scratch the surface of today’s digital power dynamics. Today, companies exert power over their users by tracking, selling data, psychological manipulation, intrusive advertising, planned obsolescence, and hostile Digital “Rights” Management (DRM) software. These issues affect every digital user, technically inclined or otherwise, on desktops and smartphones alike. - period: 2022-06 links: - title: Incarceration in Real Numbers url: https://mkorostoff.github.io/incarceration-in-real-numbers/ description: |- An infographic showing just how disproportional incarceration is in the USA. - title: >- "Idle chitchat" vs "smalltalk" url: https://news.ycombinator.com/item?id=31880345 description: |- It took me probably 7 years after moving out of my parent’s place to learn that “smalltalk” and “idle chitchat” are not necessarily the same thing [...] In my taxonomy, “idle chitchat” is talking about things. “Smalltalk” is learning about each other. “The weather sure is nice today, isn’t it?” => idle chitchat. You’re not likely to understand a person from that starting point, except that “wow look, we both like the sun”. “Where are you from? What brings you here?” => smalltalk. You’re encouraging the person to reveal some small amounts of information about themselves which you can use to probe further and hopefully find something fascinating [...] Now I take conversations with strangers (or anyone really) as a sport, as a challenge. “How can I use these precious moments we strangers share to discover something new? To leave one of us pondering something novel later in the evening” [...] _A comment from [Hacker News thread](https://news.ycombinator.com/item?id=31859072)_ - title: 13 Propositions on an Internet for a “Burning World” url: https://pure.mpg.de/rest/items/item_3390006_1/component/file_3390007/content description: |- However, up until then, we live in a burning world, i.e., one evaporating under the human-made climate emergency and countless other shifts we find ourselves in at the moment. The Internet of today will certainly neither be sustainable nor resilient in the future we are heading towards. Tobias Fiebig and Doris Aschenbrenner wrote down these thoughts in a paper in the form of “13 propositions”, which will appear in the proceedings of the joint workshops on “Technologies, Applications, and Uses of a Responsible Internet” and “Building Greener Internet”. _Also published in a series of [blog posts](https://doing-stupid-things.as59645.net/burning/world/resillience/2022/06/27/propositions-part-1.html)_ - title: Notes on the small web url: https://felix.plesoianu.ro/web/in-the-small.html description: |- There still exists a web like the one I browsed when I was a teenager. It's just not as visible anymore with all the loud giants grabbing most of attention first. - period: 2022-05 links: - title: Marginalia Search url: https://search.marginalia.nu/ description: |- Remember when you used to explore the Internet, when you used to discover cool little websites made by people and it wasn't just a bunch of low effort content mill listicles and blog spam? I want to show you that the Internet you used to go exploring is still very much there. There are still tons of small personal websites, and a wealth of long form text from both the past and the present. So it's a search engine. It's perhaps not the greatest at finding what you already knew was there. Instead it is designed to help you find some things you didn't even know you were looking for. - title: Beej's Guide to Unix IPC url: https://beej.us/guide/bgipc/html/multi/index.html description: |- These documents are meant to springboard the aforementioned user into the realm of IPC by delivering a concise overview of various IPC techniques. This is not the definitive set of documents that cover this subject, by any means. Like I said, it is designed to simply give you a foothold in this, the exciting world of IPC. - title: Google Chrome loses all saved passwords on Linux url: https://bugs.chromium.org/p/chromium/issues/detail?id=1251355 description: |- A bug from 2021 that affects about 5% of Linux Chrome installations. Password sync errors out when it encounters just one mangled row in SQLite database. Check if you're affected by this error: `chrome://sync-internals/` (look for red/green row for 'Passwords' on the right side of screen), workaround: enable `chrome://flags/#clean-undecryptable-passwords`, then toggle sync off/on. - title: Science Abridged Beyond the Point of Usefulness url: https://www.smbc-comics.com/covid/files/miniSciWebv6.pdf description: |- Aristotle said a bunch of stuff that was wrong. Galileo and Newton fixed things up. Then Einstein broke everything again. Now, we’ve basically got it all worked out, except for small stuff, big stuff, hot stuff, cold stuff, fast stuff, heavy stuff, dark stuff, turbulence, and the concept of time. _(The book is licensed under CC-BY-NC-3.0)_ - title: Cirros Linux url: https://github.com/cirros-dev/cirros description: |- _(Via [OpenStack images](https://docs.openstack.org/image-guide/obtain-images.html))_ - A minimal Linux distribution that was designed for use as a test image on clouds such as OpenStack Compute. Comes with cloud-init out of the box and supports insecure login by default (user: `cirros`, password: `gocubsgo`) - period: 2022-04 links: - title: Caroline url: https://jonathanalland.com/caroline.html description: A short story about friendship, imagination and growing up. Well written. Sad. - period: 2022-02 links: - title: Dave Gauer's Notebook System url: http://ratfactor.com/notes description: |- Looking back at ten years of logging each day into paper notebooks, transcribed into text files later (with vim plugins and shell scripts for automation) - period: 2022-01 links: - title: Extrepo url: https://grep.be/blog/en/computer/debian/Announcing_extrepo/ description: |- Manage Debian external repositories in a safe manner. Google Chrome and GitLab runner are already added into [repository database](https://salsa.debian.org/extrepo-team/extrepo-data) - title: |- GitHub stars history for my projects url: https://star-history.com/#sio/Makefile.venv&sio/LibPQ&sio/bash-complete-partial-path&Date - title: A Minimum Viable Computer, or Linux for $15 url: https://bbenchoff.github.io/pages/LinuxDevice.html description: |- A single developer designs and builds a cheap Linux handheld computer (Allwinner F1C100s, 533MHz, 32-64MB DDR, Buildroot) - title: Bufferbloat Test by: Waveform url: https://www.waveform.com/tools/bufferbloat - title: Constraint Programming url: https://en.wikipedia.org/wiki/Constraint_programming description: |- A concept that might be useful for some programming projects. There are several known algorithms with good opensource implementations, no need to attempt to solve this alone. - period: 2021-11 links: - title: The Gradual Extinction of Softness by: Chantha Nguon with Kim Green url: https://hippocampusmagazine.com/2021/11/the-gradual-extinction-of-softness-by-chantha-nguon-with-kim-green/ description: |- An essay about first hand experience of Kambodian revolution (Khmer Rouge) and fleeing to Saigon. Going from a middle class 9-year old girl to a woman in a refugee camp to a founder of Women's Development Centre back in Cambodia. - title: b4cksp4ce url: https://0x08.in/ description: A hackspace in St. Petersburg - title: Bird flew from Alaska to Australia non-stop, 8,100 miles in 239 hours url: https://www.audubon.org/news/these-mighty-shorebirds-keep-breaking-flight-records-and-you-can-follow-along description: |- Amazing that our state of the art technology is a fragile device that can fly for 30 minutes, while this ancient entity can fly nonstop, deriving energy from bugs and water, fly through storms, self repair any damage, has self navigation and local avoidance, and even can self replicate [(more comments)](https://news.ycombinator.com/item?id=29225729) - title: A philosophy for productive instant messaging url: https://drewdevault.com/2021/11/24/A-philosophy-for-instant-messaging.html description: |- An approach to instant messaging I agree with. Will probably link to this if topics comes up - period: 2021-10 links: - title: Terminal Server on a Budget url: https://blog.lasseter.org/posts/2020/07/terminal-server-on-a-budget/ description: |- Using `conserver` for out-of-band (OOB) management of whitebox servers via serial console. See also: - [Conserver](https://www.conserver.com/) - [Zonker's Greater Scroll of Console Knowledge](https://www.conserver.com/consoles/) - [Serial Console Server for the Poor](https://blog.zugschlus.de/archives/707-Serial-Console-Server-for-the-Poor-I.html) - udev rules - Using serial for out-of-band access and OS reinstallation: [FreeBSD/Ubuntu](https://adventurist.me/posts/00308), [dualboot](https://adventurist.me/posts/00307) - period: 2021-09 links: - title: Teleport Access Plane url: https://goteleport.com/ description: |- Certificate authority and access plane for SSH, kubernetes, web apps etc. Issues short-lived certificates after web based authentication. Supports session recording, access requests, live session view - period: 2021-08 links: - title: LCD Scaler Board url: https://www.display-solution.com/en/lcd-panel-control-boards/hdmi-dp-lcd-tft-scaler-board/ description: |- Turn any laptop screen into a proper monitor with a simple cheap board. Inputs: DC power, HDMI/VGA signal. Outputs: LVDS, backlight. - period: 2021-07 links: - title: SAS2Flash Utility url: https://docs.broadcom.com/doc/12355769 description: |- Quick reference guide for flashing LSI SAS controllers (SAS 2008, SAS 2308) - title: Virtualization Best Practices url: https://documentation.suse.com/sles/15-SP1/pdf/article-vt-best-practices_color_en.pdf description: |- A guide from SUSE documentation. Good explanations of Kernel Samepage Merging (KSM), memballoon, hugepages plus sane checklists for Windows guest configuration. - title: Linux routing for multiple uplinks/providers url: https://tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.rpdb.multiple-links.html description: A straightforward explanation of dual WAN setup on a Linux router - title: 'Salary Negotiation: Make More Money, Be More Valued' url: https://www.kalzumeus.com/2012/01/23/salary-negotiation/ - period: 2021-06 links: - title: Which Azure VMs support nested virtualization url: https://docs.microsoft.com/en-us/azure/virtual-machines/acu description: |- Check this list for instances marked with `***` to indicate support for nested virtualization. Best fit for my purposes are `E4ds_v4`, `D4ds_v4`, `E4s_v3` (D4 means general purpose with 4 vCPU, E4 offers extended memory with 4vCPU) - title: Inserting cage nuts in server rack without a tool url: https://www.reddit.com/r/homelab/comments/nyus92 description: |- Use two screwdrivers to save your fingers even if you don't have the special tool - title: How to run X server using xserver-xorg-video-dummy driver url: https://techoverflow.net/2019/02/23/how-to-run-x-server-using-xserver-xorg-video-dummy-driver-on-ubuntu/ description: |- Sometimes you need to use X server on a machine without a video card. Dummy driver helps in such cases - period: 2021-04 links: - title: Surprisingly Slow url: https://gregoryszorc.com/blog/2021/04/06/surprisingly-slow/ description: |- A writeup on possible performance bottlenecks with modern computing: - Automated environment detection - New process overhead - Closing file handles on Windows - Writing to Terminals - Thermal throttling / ACPI C-state, P-state - Interpreter overhead - Storage I/O - Unnecessary compression (zlib vs zstandard vs no compression) - Old baseline for x86_64 binaries - Inefficiend diff implementations (sometimes lower algorithm complexity does not result in faster runtimes) - title: Why Is Payroll Hard url: http://wiki.c2.com/?WhyIsPayrollHard description: A real world description of why business logic is almost never algorithmic - period: 2021-03 links: - title: Wealth shown to scale url: https://mkorostoff.github.io/1-pixel-wealth/ description: |- A comparison infografic with 1px = $1000 showing the scale of Jeff Bezo's fortune and that of top 400 Americans. - title: Raspberry Pi Cluster url: https://darrylcauldwell.github.io/post/homelab-pi/#finished-rack description: Laser cut aluminium case for RasPi cluster - period: 2021-02 links: - title: Girl & Computer url: https://rmurphey.medium.com/girl-computer-31ecd328bc53 description: |- A woman reminiscing about all the events leading to her working full time as a programmer, starting with her parents buying a computer in 1982, when she was a 5 year girl. - title: 'Do-nothing scripting: the key to gradual automation' url: https://blog.danslimmon.com/2019/07/15/do-nothing-scripting-the-key-to-gradual-automation/ description: |- A good idea on gradual introduction on automation into checklist/runbook-style workflows - title: On the design on text editors url: https://arxiv.org/pdf/2008.06030.pdf description: |- A short research paper that highlights numerous possibilities of text/code editor improvement with modern technology. - period: 2020-11 links: - title: Can EARLIER be used in DAX measures? url: https://javierguillen.wordpress.com/2012/02/06/can-earlier-be-used-in-dax-measures/ description: A workaround to create a row context when calculating DAX measures. - period: 2020-10 links: - title: OpenBSD Home Router url: https://0xc45.com/blog/openbsd-home-router/ description: 'A guide to building a home router from scratch: firewall, dhcp, dns' - title: PXE booting a Raspberry Pi 4 url: https://riscj.dev/projects/rpirack/posts/01.html description: Hand-on guide to setting up PXE boot for multiple clients - period: 2020-08 links: - title: What to do with a lot of on-prem compute? url: https://www.reddit.com/r/homelab/comments/iel5gz/ description: |- A group of people bought several thousand dollars worth of compute equipment and just now are thinking about how to create a profitable business out of it. - title: Tunshell url: https://github.com/TimeToogo/tunshell description: |- Easy remote shell for inaccessible hosts (e.g. double-NATed) - title: Ventoy url: https://www.ventoy.net/ description: Boot multiple live ISOs from a single USB drive - period: 2020-07 links: - title: 'TinyPilot: Build a KVM Over IP for Under $100' url: https://mtlynch.io/tinypilot/ description: |- Use Raspberry Pi to emulate mouse/keyboard via USB OTG port and to capture and broadcast video signal with HDMI-USB dongle. - title: |- Declassified writings of German generals written for training of US military immediately after World War II by: Center for Military History url: https://history.army.mil/catalog/browse/title.html description: |- - [Warfare in the Far North](https://history.army.mil/html/books/104/104-24/index.html) - [Military Improvisations in the Russian Campaign](https://history.army.mil/catalog/pubs/104/104-1.html) - [Effects of Climate on Combat in European Russia](https://history.army.mil/html/books/104/104-6/index.html) - title: Myth of the clean Wehrmacht url: https://en.wikipedia.org/wiki/Myth_of_the_clean_Wehrmacht - period: 2020-06 links: - title: Изготовление печатной платы с холодным переносом тонера url: http://myowndevice.ru/index.php/theory/item/12-delaem-pechatnuyu-platu description: |- Перенос тонера с помощью ацетона (1 часть ацетона, 2 части жидкости для снятия лака без ацетона), травление перекисью водорода и лимонной кислотой. - period: 2020-05 links: - title: Systemd service hardening url: https://github.com/alegrey91/systemd-service-hardening description: |- A short guide on how to use `systemd-analyze security` and how to harden your systemd units - title: Systemd, 10 years later url: https://blog.darknedgy.net/technology/2020/05/02/0/ description: A large essay on the history and internals of systemd - period: 2020-04 links: - title: Enabling Hyper-V enlightenments with KVM url: https://blog.wikichoon.com/2014/07/enabling-hyper-v-enlightenments-with-kvm.html description: |- KVM offers some special features that make Windows guests run faster. See also: [synic, stimer](https://bugzilla.redhat.com/show_bug.cgi?id=1610461), [hpet, hypervclock](https://www.reddit.com/r/VFIO/comments/80p1q7) - title: 'Endlessh: an SSH Tarpit' url: https://nullprogram.com/blog/2019/03/22/ description: |- Delay incoming SSH connections for weeks to trap attacker's resources. Implemented in C with a proof of concept draft in asynchronous Python. Also features a draft of HTTP tarpit. - period: 2020-03 links: - title: A half-hour to learn Rust url: https://fasterthanli.me/blog/2020/a-half-hour-to-learn-rust/ description: |- An introduction to Rust that is enough to read and understand the code you see online - title: Thin Clients Hardware database (ParkyTowers) by: David Parkinson url: https://www.parkytowers.me.uk/thin/ description: |- A thorough database of thin client hardware, with detailed photos of internal layout, description of extension capabilities and Linux support - period: 2020-02 links: - title: Why are we so bad at software engineering? url: https://www.bitlog.com/2020/02/12/why-are-we-so-bad-at-software-engineering/ description: |- Our industry’s mindset grew in an environment where failure is cheap and we are incentivized to move quickly. Our processes are poorly applied when the cost of a redo is high or a redo is impossible. - title: Docker and the PID 1 zombie reaping problem url: https://blog.phusion.nl/2015/01/20/docker-and-the-pid-1-zombie-reaping-problem/amp/ description: |- A good explanation of why PID 1 has extra responsibilities (cleaning up adopted defunct processes), plus a working example of simple init process written in Python - title: Rethinking PID 1 by: Lennart Poettering url: http://0pointer.de/blog/projects/systemd.html description: The article that started systemd era - title: Testing your Ansible roles with Molecule by: Jeff Geerling url: https://www.jeffgeerling.com/blog/2018/testing-your-ansible-roles-molecule description: Overview of automated testing for Ansible roles - title: Using molecule with GitLab CI url: https://univers-libre.net/posts/ansible-molecule-gitlab-ci.html description: Hands-on example of implementing Molecule tests in GitLab CI - title: Continuous Infrastructure with Ansible, Molecule & TravisCI url: https://blog.codecentric.de/en/2018/12/continuous-infrastructure-ansible-molecule-travisci/ description: 'A three-part series of blog posts on Molecule: scenarios, drivers, linters.' - period: 2020-01 links: - title: A philosophy of project governance by: Drew DeVault url: https://drewdevault.com/2020/01/17/Effective-project-governance.html description: |- Reflections on software projects being intrinsically social systems that can not be programmed. Good arguments on why Code of Conduct must not be elevated to the position of highest authority. - period: 2019-11 links: - title: Rate limiting algorithms url: https://en.wikipedia.org/wiki/Rate_limiting description: |- Multiple approaches to implementing rate limits in your code. - [Token bucket](https://en.wikipedia.org/wiki/Token_bucket), also: in use with Python [aiohttp](https://quentin.pradet.me/blog/how-do-you-rate-limit-calls-with-aiohttp.html) - [Leaky bucket](https://en.wikipedia.org/wiki/Leaky_bucket) - Fixed window counter - Sliding window log - [Sliding window counter](https://medium.com/figma-design/an-alternative-approach-to-rate-limiting-f8a06cf7c94c) - period: 2019-10 links: - title: Detecting the use of "curl | bash" server side url: https://www.idontplaydarts.com/2016/04/detecting-curl-pipe-bash-server-side/ description: |- Piping curl to shell may be detected via HTTP fetching delays even if User Agent is masked. Requires lots of null-byte padding though. - title: Patch workflow with Mutt by: Greg Kroah-Hartman url: http://kroah.com/log/blog/2019/08/14/patch-workflow-with-mutt-2019/ description: |- Detailed description of email based kernel dev workflow. Notable references: [isync/mbsync](http://isync.sourceforge.net/), [aerc](https://aerc-mail.org/) - title: Noto Color Emoji Font url: https://www.google.com/get/noto/#emoji-zsye-color description: |- Add this to `~/.fonts` to enable emoji rendering in Debian 9. Available in Debian repos for Buster+ (10+) - period: 2019-08 links: - title: Software Usability II, Tom Davis url: http://www.art.net/%7Ehopkins/Don/unix-haters/tirix/embarrassing-memo.html description: |- Internal SGI memo (1993) regarding performance issues in their latest release. The problems highlighted there are not unique to that company or that time period, they frequently appear in all large software development projects nowadays. *This article is part of Unix Haters Handbook*. - title: Packaging Python projects url: https://hynek.me/articles/testing-packaging/ description: |- Turns out there is a technical reason for putting Python code under `src/` directory in your repo. It makes easier to spot errors in `setup.cfg` and `MANIFEST.in`. See also: [Packaging a Python library](https://blog.ionelmc.ro/2014/05/25/python-packaging/#the-structure) - title: C Is Not a Low-level Language url: https://queue.acm.org/detail.cfm?id=3212479 description: |- C was a good low-level abstraction in the era of PDP-11 but it is less so now. Parallel programming should not be hard, future hardware could make it better by dropping some C compatibility. - period: 2019-07 links: - title: Consider Using Asciidoctor for Your Next Presentation url: https://matklad.github.io/2019/05/19/consider-using-asciidoctor-for-your-next-presentation.html description: |- Asciidoc is a nice format to write documentation, this is what it can do for presentations. - title: Nifty Assignments by: Stanford University url: http://nifty.stanford.edu/ description: |- A collection of unusual and interesting assignments for learning programming - title: RISC Is Fundamentally Unscalable url: https://erikmcclure.com/blog/risc-is-fundamentally-unscalable/ description: |- Overview of upcoming issues in microprocessor design when current scaling techniques will stop working. Wow moment: the speed of light is now a limiting factor when designing CPUs. Includes some hints that VLIW architecture might be the future (see: Intel Itanium project) - period: 2019-06 links: - title: Мошенники и ЭЦП url: https://habr.com/ru/post/453596/ description: |- Использование поддельной электронно-цифровой подписи для мошенничества (создание юридических лиц, сделки с недвижимостью) - title: 'A belief in meritocracy is not only false: it’s bad for you' url: https://bigthink.com/politics-current-affairs/a-belief-in-meritocracy-is-not-only-false-its-bad-for-you