Pikchr (pronounced "picture") is a PIC-like markup language for diagrams in technical documentation. Pikchr is designed to be embedded in fenced code blocks of Markdown or similar mechanisms of other documentation markup languages.
Pikchr source code is released under a zero-clause BSD license.

This suite of open source tools is the software development platform you've been waiting for. We've taken the wisdom of the most successful open-source communities and turned it into a platform of efficient engineering tools.

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Sourcehut is currently (2020-09) available as a public alpha.
Note that it includes a Plan9(front) continuous integration service
https://sourcehut.org/blog/2020-05-11-sourcehut-plus-plan-9/

Recommended by Brett Gilio
https://brettgilio.com/posts/2020-10-01-why-self-host.html

David Rosenthal's blog. Other interesting articles include
https://blog.dshr.org/2020/05/the-death-of-corporate-research-labs.html
https://blog.dshr.org/2020/06/informational-capitalism.html
https://blog.dshr.org/2020/03/more-on-failures-from-fast-2020.html

ISA-L is a collection of optimized low-level functions targeting storage applications. ISA-L includes:
   Erasure codes - Fast block Reed-Solomon type erasure codes for any encode/decode matrix in GF(2^8).
   CRC - Fast implementations of cyclic redundancy check. Six different polynomials supported.
       iscsi32, ieee32, t10dif, ecma64, iso64, jones64.
   Raid - calculate and operate on XOR and P+Q parity found in common RAID implementations.
   Compression - Fast deflate-compatible data compression.
   De-compression - Fast inflate-compatible data compression.
BSD 3-Clause "New" or "Revised" License.
According to https://github.com/catid/cm256, ISA-L uses a O(N^3) Gaussian elimination solver for decoding. The CM256 decoder solves the linear system using a fast O(N^2) LDU-decomposition algorithm from "Pivoting and Backward Stability of Fast Algorithms for Solving Cauchy Linear Equations" (T. Boros, T. Kailath, V. Olshevsky), which was hand-optimized for memory accesses.
See also https://github.com/catid/leopard for a fast O(N log(N)) RS erasure decoder.

Welcome! Funtoo Linux (distrowatch) is a community-developed Linux meta-distribution based upon Gentoo Linux. Funtoo Linux is optimized for the best possible performance on the latest Intel and AMD hardware. Funtoo is led by Daniel Robbins, the creator of Gentoo Linux, and actively developed by the Funtoo community.
Funtoo does not use systemd, but OpenRC https://www.funtoo.org/FAQ:Do_You_Support_Systemd

VBinDiff (Visual Binary Diff) displays files in hexadecimal and ASCII (or EBCDIC). It can also display two files at once, and highlight the differences between them. Unlike diff, it works well with large files (up to 4 GB).

Code is at
https://github.com/larsmagne/eval-server.el

The long term goal of the Software Heritage initiative is to collect all publicly available software in source code form together with its development history, replicate it massively to ensure its preservation, and share it with everyone who needs it. The Software Heritage archive is growing over time as we crawl new source code from software projects and development forges.

gphoto-sync is an open source command-line tool written in Python. It’s purpose is to backup Google Photos and Albums using the Google Photos Library API. Once setup, it can be run on a regular basis, to ensure all the pictures stored in the cloud are also stored locally on your own storage.

TinyScheme is a lightweight Scheme interpreter that implements as large a subset of R5RS as was possible without getting very large and complicated. It is meant to be used as an embedded scripting interpreter for other programs. As such, it does not offer IDEs or extensive toolkits although it does sport a small top-level loop, included conditionally. A lot of functionality in TinyScheme is included conditionally, to allow developers freedom in balancing features and footprint.