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+Who I am (it's a little bit relevant to understand my previous knowledge)
+- telecommunication engineer (EEE equivalent)
+- Freelance engineer/programmer at ElenQ.Tech
+- Guix user and contributor
+
+Recently:
+- Interested in small computing
+- Lisp, specially scheme, specially small scheme implementations
+
+The early beginnings:
+- Started a very small scheme compiler for small machines, and thought
+  about RISC-V. I decided to target RISC-V assembly (following:
+  https://compilers.iecc.com/crenshaw/)
+- I studied RISC-V via [riscvbook]
+- I studied several scheme implementations
+- Nothing happened out of this, I gave up when I read about continuations but I
+  learned some stuff.
+
+The random events
+- One day a friend tells me guix mailing list is looking for help to make a
+  RISC-V port. I decide to raise my hand.
+- Now I'm involved in RISC-V porting effort somehow.
+- One day Andy Wingo, the Guile maintainer, mentions it would be interesting
+  to port Lightening, Guile's JIT code generation library to RISC-V.
+
+Now I'm working on Lightening: things learned
+- Code is data -> I'm a lisp guy, I already knew that!
+- Some cool GDB debugging I already forgot (disassemble)
+- Now I'm able to hand-assemble instructions too
+- Machine code generation is not that complex
+- Relocations and large immediates are painful
+
+Lightening RISC-V is passing all the tests, next step is to give it a serious
+try and see if it works! Cross fingers!
+
+Stage0
+- There was a chance to work on the bootstrap system of Guix via NlNet and the
+  guys involved in the porting effort helped me prepare a proposal.
+- I had to learn about all the steps around so I started with Stage0.
+
+Stage0's steps:
+hex0 -> hex1 -> hex2 -> M0 (macro system) -> M2-Planet [ -> Gnu Mes ]
+
+Hex0
+- Hex0 are hex files that contain what the ELF executable would, but encoded in
+  Hexadecimal text.
+- I started with hex0, porting it to RISC-V (RV64). Thankfully, I was
+  developing a RISC-V assembler (I never finished) that helped me generate the
+  instructions by hand.
+- Took the ELF headers from the wikipedia.
+- It worked!!
+
+Effects of this effort
+- Other people at Bootstrappable took this work and finished the whole chain
+  of Stage0!
+
+A random afternoon:
+- I was bored and the Hex0 for RV32 was missing. Looked the headers in the
+  wikipedia and 20 minutes later it was added to the project. Another starting
+  point solved!
+
+Now:
+- Took the NlNet grant and now I'm going to contribute to the full source 
+  bootstrap ecosystem. So now this is kind of my job.
+
+Conclusions:
+- This is just random work
+- Embrace the randomness of life, stay curious and you may reach interesting
+  places.
+
+
+
+---
+
+
+My blogposts about this process:
+https://ekaitz.elenq.tech/lightening.html
+https://ekaitz.elenq.tech/hex0.html
+https://ekaitz.elenq.tech/machine-code-generation.html
+
+RISC-V:
+http://riscvbook.com/
+
+Bootstrap related:
+http://bootstrappable.org
+https://github.com/oriansj/stage0
+https://github.com/oriansj/bootstrap-seeds
+
+GUILE
+https://www.gnu.org/software/guile/
+https://gitlab.com/wingo/lightening/-/merge_requests/14/commits
+
+---
+
+We are excited to announce a devroom on Declarative and Minimalistic
+Computing at FOSDEM on 5th and 6th of February, 2022, online!
+
+FOSDEM is one of the most important free software conferences and is
+hosted annually at Université libre de Bruxelles in Brussels,
+Belgium. Unfortunately again this year FOSDEM will not run a physical
+conference but will be online only. Talks will be pre-recorded with
+some live content including Q&A sessions and discussion panels.
+
+We accept talks from languages that attempt to minimize use of hardware
+and software while trying to make systems simpler, more robust and more
+secure. If you are working on improving today's systems taking
+declarative/minimalistic approaches feel free to submit a talk
+proposal. Examples include the Scheme/Lisp family of programmings
+languages. In past editions, this devroom has received presentations
+from a varied number of language communities, including Forth, Guile,
+Lua, Nim, Racket, Raku and Tcl as well as several experimental projects
+that push minimalism in new directions.
+
+Minimalism and declarative programming are two important topics for
+this devroom. Minimalism matters. Minimalism allows for smaller
+systems that take less resources and consume less energy. More
+importantly, free and open source minimalism allows for secure systems
+that are easy to understand. Declarative programming is a programming
+paradigm that expresses the logic of a computation without describing
+its control flow. Many languages that apply this style attempt to
+minimize or eliminate side effects by describing what the program must
+accomplish in terms of the problem domain, rather than describe how to
+accomplish it as a sequence of the programming language primitives.
+
+Finally, in this year's virtual conference we will honor the late Professor
+[https://en.wikipedia.org/wiki/John_McCarthy_(computer_scientist) John
+McCarthy] as the founder of AI and the inventor of LISP. McCarthy with
+his work pioneered artificial intelligence, developed the Lisp
+programming language family and kickstarted our modern computing world.
+
+We want to invite you to submit a talk on declarative and minimalistic
+computing that fits that description. We are especially happy to
+receive talk submissions from members of groups underrepresented in
+free software.
+
+If you have something you’d like to share with your fellow developers,
+please E-mail us! Talks considered for the devroom will have to
+be entered in
+
+   - https://penta.fosdem.org/submission/FOSDEM22
+
+The deadline for submission is December 20th. If you have a FOSDEM
+pentabarf account from a previous year, please use that
+account. Otherwise add one on
+https://penta.fosdem.org/user/new_account. Reach out to
+pjotr.public456@thebird.nl or manolis837@gmail.com if you run into any
+trouble.
+
+When submitting your talk make doubly sure to select "Declarative and
+Minimalistic Computing devroom" as track (if you don't we won't find
+it), and include the following information:
+
+   * The title and subtitle of your talk
+   * A short abstract of one paragraph
+   * A longer description if you wish to do so
+   * Links to related websites/blogs etc
+   * Presentations has to be pre-recorded and streamed before the event.
+   * Start recording early!
+
+To see what a final talk looks like see
+
+   https://archive.fosdem.org/2021/schedule/event/gnumes/
+
+For accepted talks
+
+   * Once your talk was accepted, we will assign you an organizer to
+help you to produce the pre-recorded content.
+   * The organizer will review the content and ensure it has the
+required quality. He is also responsible for ensuring the content is
+into the system and ready to broadcast.
+   * During the stream of your talk, you must be available online for
+the Q/A session
+
+Let's make this a fun day!
+
+= Organizers =
+
+Pjotr Prins, Manolis Ragkousis, Ludovic Courtès, Amirouche Boubekki,
+Hisham Muhammad, Jan Nieuwenhuizen, Ricardo Wurmus, Alex
+Sassmannshausen, William Byrd, Oliver Propst, Efraim Flashner, Julien
+Lepiller
+
+= Code of conduct =
+
+   - https://fosdem.org/2022/practical/conduct/
+
+= Original proposal =
+
+   - https://libreplanet.org/wiki/FOSDEM2022-devroom-proposal
+
+= Important dates: =
+
+   - Dec 20th 2021:  submission deadline for talk proposals
+   - Dec 31th 2021:  announcement of the final schedule
+   - Jan 14th 2021:  submission deadline for recordings
+   - Feb  5th 2022:  FOSDEM!
+
+= Links: =
+
+    -
+https://libreplanet.org/wiki/FOSDEM2022-devroom-declarative-and-minimalistic-computing-cfp
diff --git a/Fosdem2022/contents.md b/Fosdem2022/contents.md
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+---
+title: "A year of RISC-V adventures: embracing chaos in your software journey"
+
+subtitle: How I started from zero and ended up porting a JIT compilation library and assembling files by hand
+
+license: CC-BY-SA
+author: Ekaitz Zárraga
+links-as-notes: true
+lang: spanish
+polyglossia-lang:
+    name: english
+how-to: pandoc -f markdown+smart -t beamer contents.md -o beamer.pdf --pdf-engine=xelatex --template=template.tex
+...
+
+# Who I am
+- Telecommunication engineer (EEE equivalent)
+- Freelance engineer/programmer at [ElenQ.Tech](https://elenq.tech)
+- Guix user and contributor
+
+## Recently
+- Interested in small computing
+- Lisp, specially Scheme, more specifically small Scheme implementations.
+
+
+
+# The beginnings
+- Started a very small scheme compiler for small machines, and thought about
+  RISC-V. I decided to target RISC-V assembly following ["Let's Build a
+  Compiler" by Jack Crenshaw](https://compilers.iecc.com/crenshaw/)
+- I studied RISC-V with: ["The RISC-V Reader: An Open Architecture
+  Atlas"](http://riscvbook.com/)
+- I studied several scheme implementations and read some papers
+- Nothing happened out of this, I gave up when I read about continuations but I
+  learned some stuff.
+
+
+
+# Chaos starts
+- One day a friend (the same guy who introduced me to Guix) tells me the Guix
+  mailing list is looking for help to make a RISC-V port. I decide to raise my
+  hand.
+- Now I'm involved in RISC-V porting effort somehow.
+- One day Andy Wingo, the Guile maintainer, mentions it would be interesting to
+  port Lightening, Guile's JIT code generation library to RISC-V.
+
+
+
+# Now I'm working on the Lightening port somehow
+
+Lightening is a machine code generation library. It's a fork of GNU Lightning,
+made for Guile, that aims to be simple.
+
+## The experience
+- My C programming skills are rusty
+- 0 documentation: only the one inherited from GNU Lightning
+- Dead code
+- Andy Wingo helped me take the good direction and made everything easier
+
+# Lightening: Things learned
+- How to assemble instructions by hand *
+- Code is data. I'm a lisp guy, I already knew that! *
+- Some cool GDB debugging tricks I already forgot
+- Machine code generation is not that complex
+- Relocations and immediates are painful[^more]
+
+[^more]: Read more: <https://ekaitz.elenq.tech/machine-code-generation.html>
+
+# Lightening: Assemble by hand
+
+```
+addi a0, zero, 56
+```
+
+- Opcode `addi`: `0010011`
+- Destination register `a0`: `01010`
+- `funct3`: `000`
+- Source register `zero`: `00000`
+- The immediate `56`: `000000111000`
+
+`000000111000 | 00000 | 000 | 01010 | 0010011`
+
+All together: `00000011100000000000010100010011`  
+(In hex: `0x3800513`)
+
+
+# Lightening: Code is data
+
+``` c
+#include<stdint.h>
+#include<stdio.h>
+
+typedef int f0(void);
+
+int main(int argc, char* argv[]){
+    uint32_t instructions[2];
+
+    instructions[0] = 0x03800513; // addi a0, zero, 56
+    instructions[1] = 0x00008067; // jalr zero, ra, 0
+
+    // Reinterpret the array address as a function
+    f0 *load_56 = (f0*) instructions;
+
+    int a = load_56();
+    printf("%d\n", a);
+}
+```
+
+
+# Moving to the bootstrap system
+
+There was a chance to work on Guix's RISC-V support via NlNet and the
+guys involved in the porting effort told me I should send a proposal.
+
+I had to learn about the full-source bootstrap project for this so I ended up
+taking part on it.
+
+The proposal was rejected, but the learning was already done. *And what now?*
+
+# Stage0
+
+Stage0 is a full source bootstrap system.
+
+Stage0's steps:
+
+1. Hex0: Hex encoded raw ELF file with comments
+2. Hex1: Hex0 + one character labels and some extras
+3. Hex2: Hex1 + proper labels and reasonable basics
+4. M0 (macro system): A simple macro system
+5. M2-Planet: A C subset that uses M0 as output
+6. C compilers (i.e. GNU Mes's `mescc`)
+
+
+# Stage0
+
+## The experience
+
+![](img/better_documentation.png)
+
+# Hex0
+
+Hex0 is a simple assembler written in Hex0. It just converts a Hexadecimal
+encoded ELF file to binary.
+
+It's heavily commented so anyone can decode the instructions and make sure that
+it works as expected. It looks like this:
+
+```
+# :_start ; (0x0600078)
+
+; Open input file and store FD in s2
+93 08 80 03    # RD_A7 !56 ADDI      ; sys_openat
+13 05 C0 F9    # RD_A0 !-100 ADDI    ; AT_FDCWD
+93 05 06 00    # RD_A1 RS1_A2 MV     ; input file
+13 06 00 00    # RD_A2 MV            ; read only
+73 00 00 00    # ECALL
+13 09 05 00    # RD_S2 RS1_A0 MV     ; Save fd
+
+```
+
+# Hex0
+
+I wanted to make the first version of the POSIX based Hex0 for RV64. I just
+needed to:
+
+1. Write it in assembly first
+2. Assemble everything by hand...
+
+![](img/drake.jpg)
+
+
+
+# Hex0: Abandoned projects that add entropy: pysc-v
+
+While I was working on Lightening I started a RISC-V assembler in Python.
+
+*[I abandoned the project](http://git.elenq.tech/pysc-v/)*
+
+But the backend was reusable so I could generate all the instructions in the
+Hex0 with the format I wanted!
+
+
+# Hex0: disassembly tricks
+
+I still need to calculate addresses by hand though.
+
+*But wait!* I learned how to disassemble when I worked on Lightening so I could
+obtain each instructions address easily, without all the counting.
+
+# Hex0
+
+## The experience
+
+- It was rewarding to see that I could write assembly.
+- I reused all the GDB tricks from Lightening to check that everything was
+  working correctly.
+- The documentation is weird and there are too many subprojects that make the
+  project hard to understand for newcomers. It's hard to understand the reasons
+  behind some decisions and everything looks fragile.
+- But `#bootstrappable` at `libera.chat` is a good place to ask questions and
+  learn from others.
+
+
+# Hex0 extra: embrace boredom
+
+Sunday morning. I'm bored.
+
+I reviewed the status of the project and saw RV32 is not ready yet, even if it
+is similar to RV64.
+
+I start a discussion on IRC and in less than half an hour and with the help of
+the Wikipedia we replace the ELF headers and make the Hex0 support for RV32.
+
+
+# Status of the projects
+- **Lightening**: is passing all the test but needs testing. [The
+  code][lightening] is available for anyone to read and improve.
+- **Stage0**: included [my small RISC-V contribution to Hex0][stage0] and other
+  contributors expanded my work to every stage.
+
+[lightening]: https://gitlab.com/wingo/lightening/-/merge_requests/14/commits
+[stage0]: https://github.com/oriansj/bootstrap-seeds/pull/2
+
+
+
+# My status
+
+I tried again with NlNet, with a proposal for some RISC-V porting efforts on
+GNU Mes and other bootstrap related projects.
+
+They look interested on a full-source-bootstrap for RISC-V!
+
+*I might end up working on a compiler*
+
+
+# Conclusions
+- All this is just random work, done without a plan or purpose
+- Embrace the chaos of life, stay curious and you may reach interesting places
+- If you can, learn from people: it's faster and better
+- You don't need to be a genius: most of the things are easy once you know the
+  context.
+
+---
+
+## Just try, and let it happen
diff --git a/Fosdem2022/img/better_documentation.png b/Fosdem2022/img/better_documentation.png
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diff --git a/Fosdem2022/img/drake.jpg b/Fosdem2022/img/drake.jpg
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diff --git a/Fosdem2022/template.tex b/Fosdem2022/template.tex
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