Decentralized meta-learning

AI Tools Pricing Comparison

Sat, 03 Jan 2026 00:00:00 +0000

This document provides a comprehensive comparison of pricing plans across AI coding agents, IDEs, and coding APIs that I frequently use.

Understanding Digital Certificates

Thu, 31 Jul 2025 00:00:00 +0000

A digital certificate, specifically an X.509 digital certificate, is a standardized electronic document that binds a public key to an identity. It's like a digital ID card, issued and signed by a trusted third party, the Certificate Authority (CA), to verify the authenticity of a public key.

ATM Implied Volatility for Constant Maturity Term Structure

Mon, 30 Jun 2025 00:00:00 +0000

A primer to Implied Volatility, Constant Maturity, Term Structure. Enjoy the presentation!

Warning: Prior options trading knowledge is needed! if you do not know how payoff diagram for a CALL option looks like then these slides are not for you.

OneRidge: Southern Carpathians

Wed, 30 Apr 2025 00:00:00 +0000

The Southern Carpathians (also known as the Transylvanian Alps) extend approximately 300km from the Prahova Valley in the east to the Iron Gates in the west, forming the highest and most rugged section of Romania's Carpathian chain.

Bonds summary

Fri, 28 Mar 2025 00:00:00 +0000

The bond market uses several important rate/date/price concepts that investors need to understand. Here's an explanation of the most significant ones.

OneRidge: Western Carpathians

Thu, 27 Feb 2025 00:00:00 +0000

The Western Carpathians (Apuseni Mountains) form a distinct mountain group in northwestern Romania, separated from the main Carpathian chain by the Transylvanian Plateau.

Unit Testing Elixir

Fri, 31 Jan 2025 00:00:00 +0000

Tips & tricks for testing Elixir applications… there are tons of libraries for testing, each one with different syntactic sugar, runtime (sync vs. async) and implementation details but all we need for unit testing are these 3: ExUnit, Hammox and Mimic.

OneRidge: Eastern Carpathians

Sat, 21 Dec 2024 00:00:00 +0000

The Eastern Carpathians stretch approximately 600km through northeastern Romania, running through the historical regions of Maramures, Bukovina, and Moldova.

The Power of Mnesia

Thu, 21 Nov 2024 00:00:00 +0000

Mnesia is the master-less distributed storage built-in Erlang and by default it inherits all the goodies of Erlang cluster distribution. Lets give it a try.

OneRidge

Wed, 30 Oct 2024 00:00:00 +0000

Uniting the Carpathians through a continuous trekking route

The mission of OneRidge project is to design and establish a continuous trekking route(s) that spans the length of Romania’s Carpathian Mountains, starting from the Iron Gates in the southwest and stretching all the way to the northern border with Ukraine.

Click, Percent, Zscore changes

Wed, 18 Sep 2024 00:00:00 +0000

As a wise man once said:

beginners think in $ change,
intermediates think in % change,
pros think in Z change.

Introducing new Tradingview Outlier changes alert indicator that calculates click (price change), percentage change, and Z-score (standard deviation multiple) changes while displaying outliers based on defined ranges.

SSL-offloader for Dokku

Tue, 26 Sep 2023 00:00:00 +0000

I use Dokku as Platform As A Service (PaaS) tool, which is very convenient until you have dozen of apps deployed (like I do) and hit Let's Encrypt limits.

Functional architecture

Tue, 14 Mar 2023 00:00:00 +0000

A functional architecture design with a "functional core" layer for business logic, then a "state servers" layer for state management and finally an "imperative shells" layer for side-effects.

Personal VPN server

Tue, 28 Feb 2023 00:00:00 +0000

I was not a big fan of traditional VPN services (which are highly centralized and slow) until Wireguard has arrived and was merged into Linux Kernel; a VPN for this century, peer to peer with state of the art cryptography.

Risk-adjusted performance metrics

Fri, 27 Jan 2023 00:00:00 +0000

You can easily double the investment and also double your return right? Not really… read on to see a few metrics that I use.

Wildcard SSL certificate

Mon, 19 Dec 2022 00:00:00 +0000

Self-generated certificate is good for bootstrapping purpose but sooner than later we need a valid SSL certificate for all services (IMAPS, HTTPS, DoT etc).

5kW off-grid photovoltaic system

Thu, 17 Nov 2022 00:00:00 +0000

DoItYourself photovoltaic 5kW off-grid system with components, references, specifications, materials, cost breakdown by each component and more.

Annapurna circuit - the aftermath

Mon, 31 Oct 2022 00:00:00 +0000

Here is day by day itinerary with trekking information, cost for food/drinks/accommodation and also a few DOs/DONTs…

Firewall, monitor, ban. Repeat.

Wed, 07 Sep 2022 00:00:00 +0000

Having an internet facing public server requires a bit of monitoring and security to keep bad actors out.

Annapurna circuit - the training

Wed, 17 Aug 2022 00:00:00 +0000

Here is the 4-week training plan for Annapurna Circuit, a bit different than Gasherbrum2 training plan for a few reasons:

Annapurna circuit - the gear

Mon, 08 Aug 2022 00:00:00 +0000

Here is the final gear list for Annapurna Circuit keeping in mind that we will experience multiple climates:

Personal DNS server

Mon, 01 Aug 2022 00:00:00 +0000

After personal Email server the next thing to setup is a Domain Name Server (DNS) server for costan․ro domain with DNSSEC, TLS and everything in between.

Annapurna circuit - the plan

Thu, 28 Jul 2022 00:00:00 +0000

Here is the initial plan for Annapurna Circuit, segment by segment with highlights, notes and everything that is interesting along the way. Updates as I do more research.

BLS signature scheme

Tue, 28 Jun 2022 00:00:00 +0000

From a high level perspective this is how BLS (also known as Boneh–Lynn–Shacham) signature scheme works.

Schnorr and taproot by hand

Wed, 15 Jun 2022 00:00:00 +0000

References

BIPs

Reminiscences of ... a loss

Thu, 26 May 2022 00:00:00 +0000

Never ask a trader how much he makes but how much he lost… here is a story…

Personal email server

Wed, 27 Apr 2022 00:00:00 +0000

Given that GMail with cease to provide free hosting service for custom domains I've decided to deploy a fully featured personal email server and migrate everything to my Arch Linux box.

SSH keys on USB

Tue, 15 Mar 2022 00:00:00 +0000

This is how I keep my SSH key(s) secure and offline, stored on encrypted USB flash-drive. After restart, unlock the drive on USB insert, automatically load the key then umount, lock, back to safety.

Completion system

Tue, 22 Feb 2022 00:00:00 +0000

Completion system

… vertico, consult, posframe, orderless, marginalia, projectile … corfu, cape, eglot, kind-icon … Ohhh my!

Chess vs. trading

Tue, 11 Jan 2022 00:00:00 +0000

Just for fun (and maybe some profit) let's do a comparison (a bit far fetched) between chess and trading.

From HDD to SSD w/ EFI boot

Tue, 21 Dec 2021 00:00:00 +0000

Oh, Oh! Santa is back in town and I bought myself a small gift to upgrade my Arch Linux garage server from HDD to SSD, here is the step-by-step how to…

Segwit transaction by hand

Thu, 25 Nov 2021 00:00:00 +0000

Lets hand craft a SegWit transaction using only built-in Python3 functions for hex/bytes manipulation and Sagemath for elliptic curves arithmetic.

Price (HLC) breaks indicator

Sat, 16 Oct 2021 00:00:00 +0000

Maybe one of the most effective indicator that I use on daily basis, Price breaks.

Again and again you can see how previous day/week/month's high/low and especially close act as support/resistance and how price bounces off these levels.

Use Linux kernel module

Thu, 30 Sep 2021 00:00:00 +0000

In Part 1 I wrote a simple Linux kernel module, called World, in Part 2 I configured that module, now it's time to use that module from within kernel space (another kernel module).

Linear vs log returns

Tue, 14 Sep 2021 00:00:00 +0000

The curse and the blessing of returns … additive vs. compounding land and what are the PROs/CONs between them.

Gasherbrum2 - the web app

Fri, 27 Aug 2021 00:00:00 +0000

One of the most important things in mountaineering is the weather, so ladies and gentlemen, I present you Gasherbrum2 web app (not very inspired name, but it is what it is).

Gasherbrum2 - the aftermath

Thu, 12 Aug 2021 00:00:00 +0000

To make a long story short I am going to lay down only a few DOs/DON'Ts (as a reminder for myself), the raw and uncut (but spellchecked) journal, and the expenses for the curious minds.

Gasherbrum2 - how to compare gear

Thu, 27 May 2021 00:00:00 +0000

I need to choose between a 229 EUR down hoody that weights 319g and one that is 269 EUR and 420g… which one will you go for?

Gasherbrum2 - gear list

Mon, 10 May 2021 00:00:00 +0000

Always changing gear list, updated for high altitude mountaineering Gasherbrum2 expedition.

Naming conventions:

type - product category, REQUIRED (e.g. sleeping bag)
brand:

Gasherbrum2 - training plan

Thu, 15 Apr 2021 00:00:00 +0000

With only two months remaining until the Gasherbrum2 expedition I put together a training plan, kind of writting in stone, let's see how it goes.

New Market Wizards

Wed, 07 Apr 2021 00:00:00 +0000

The second market wizards book, named simply New Market Wizards was actually published before the Hedge Fund Market Wizards book, a bit older but as the saying goes… oldies but goldies.

Bias vs. Variance

Tue, 30 Mar 2021 00:00:00 +0000

I don't know about others but when I started digging into machine-learning I had some problems understanding bias-variance until I found a nice target shooting analogy.

Historical volatility

Wed, 17 Mar 2021 00:00:00 +0000

Historical volatility (also called realized volatility) measures how far the normal standard deviation is from expected mean, over a given period of time.

Whale alert

Sat, 27 Feb 2021 00:00:00 +0000

Very simple pivot-point indicator that tries to detect whales' presence by checking the spikes in volume at the same UTC hour for the last 3 days.

Incomplete guide to Options Greeks

Tue, 16 Feb 2021 00:00:00 +0000

Greeks or Options Greeks are tools/statistics which measure sensitivity (responsiveness, calculus anyone?) of option price to changes in various parameters: underlying price, volatility, time, etc…

Black-Scholes formula

Thu, 28 Jan 2021 00:00:00 +0000

Black-Scholes formula… maybe not as important and well-known as compounding interest-rate but still the most famous formula among options traders. Here are the formulas that you will find in financial books.

Year 2020

Tue, 05 Jan 2021 00:00:00 +0000

Pam, pam, pam !!!

Bloody fucking year, 2020, one of a kind, already in history books.

Ternary (trinary) vs. binary

Wed, 30 Dec 2020 00:00:00 +0000

We all know the binary system but a few heard about ternary (trinary) system; one of the first computer in Soviet Russia was using ternary system but it went out of fashion and binary system took over.

Generate IOTA address

Mon, 28 Dec 2020 00:00:00 +0000

Generate IOTA address using plain old Python, starting with random seed, derive private key, and finally the checksum and address.

Interest rate

Tue, 24 Nov 2020 00:00:00 +0000

Compound interest is the eighth wonder of the world

He who understands it… earns it!
He who doesn't … pays it!

– Albert Einstein

Algebraic structures: Set, Group, Ring

Wed, 11 Nov 2020 00:00:00 +0000

The easiest way to understand algebraic structures, starting with basic structure called Set and incrementally add properties on top of it to build more complex structures.

Generate Ethereum Address

Tue, 27 Oct 2020 00:00:00 +0000

Generate Ethereum address from private key using plain old Python3, Elliptic Curve multiplication from SageMath and of course Keccak hash function.

Session breaks

Fri, 09 Oct 2020 00:00:00 +0000

The most successful indicator so far is "Session breaks" that renders vertical lines for open hour of each trading session.

First USA visit

Fri, 25 Sep 2020 00:00:00 +0000

It's been 20 fuckin' years since I set foot on the US soil for the very first time…

Hash functions

Tue, 15 Sep 2020 00:00:00 +0000

In simple terms, hash functions transform input data of arbitrary size (e.g. text, binary, etc) to fixed-length output (called hash value, hash code, fingerprint, message digest or simply hash) in a deterministic way. What else?

Config Linux kernel module

Tue, 25 Aug 2020 00:00:00 +0000

In Part 1 I created a simple World module, now it's time to configure it and there are 3 main ways to do it:

Organizing work/life projects

Tue, 11 Aug 2020 00:00:00 +0000

Here is my simple yet powerful organization style, it might not work for every person but it works for me and this is the most imporant after all, to find your own productivity style.

Hedge Fund Market Wizards

Tue, 28 Jul 2020 00:00:00 +0000

An actionable, bullet points summary for one of my favorite, all time best-seller and trading bible: Hedge Fund Market Wizards book, released in 2012.

Generate Monero address

Sat, 18 Jul 2020 00:00:00 +0000

Generate Monero address from the root private key using plain old Python, Edwards curve's ed25519 implementation, Keccak-256 hashing and Monero's Base58 encoding.

Outpost, Toong, Clockin coworking

Wed, 24 Jun 2020 00:00:00 +0000

A very short review of 3 coworking spaces in 3 countries by 4 different criteria: space, crowd, amenities, and location.

BigO complexity with graphs

Thu, 04 Jun 2020 00:00:00 +0000

Overview

Big-O notation or Big Omicron (e.g. Ο(n)) also called "asymptotic growth" notation is used to represent the worst-case scenario (the upper bound) for a given algorithm.

High-end Maldives

Sat, 23 May 2020 00:00:00 +0000

The one and only, Maldives! With private islands, luxury resorts, water/beach villas and fine dining, is one of the most expensive destination on Earth.

COVID-19 indicators

Thu, 07 May 2020 00:00:00 +0000

I wrote a few indicators showing COVID-19 daily change/momentum for the entire world, EU vs. US and for most affected countries that have either more than 10k confirmed cases or more than 1k deaths.

Introducing Huveragy

Mon, 27 Apr 2020 00:00:00 +0000

A simple Hugo partial template that renders a world coverage map using jVectorMap SVG library and dataset from Natural Earth.

Files/windows navigation

Sat, 04 Apr 2020 00:00:00 +0000

In Part 1 of Emacs series I presented the movement (or navigation within a single buffer/window), in this part I am going to demo the navigation between multiple windows/files/buffers.

Write Linux kernel module

Tue, 24 Mar 2020 00:00:00 +0000

I am thinking to start a Linux Kernel series and write about modules, device drivers, proc and sysfs, unit test with kunit and so on; here is the first one, a simple World module.

Protect your digital life

Tue, 10 Mar 2020 00:00:00 +0000

This is how I keep all my data secure, encrypted and in sync between 2 phones (ePhone, my Google-free phone and one iPhone), 2 laptops (Lenovo, my Linux machine and a Macbook) and one desktop (an older iMac).

Commitment schemes

Tue, 25 Feb 2020 00:00:00 +0000

A cryptographic commitment scheme is a way of committing to a statement without revealing the statement itself or reveal it at a later time.

Bech32 segwit address

Mon, 10 Feb 2020 00:00:00 +0000

This is how to generate a Bech32 native segwit address in just a few lines of ZSH shell.

Diving Palawan

Tue, 21 Jan 2020 00:00:00 +0000

I stayed 3 weeks on Palawan island (El Nido in the north and Puerto Princesa in the south) in Philippines and spent 1600 EUR.

Year 2019

Mon, 06 Jan 2020 00:00:00 +0000

Another year … another year passed by, I am getting older, getting wiser, here are the highlights of the year.

Backpacking Viet Nam

Sat, 21 Dec 2019 00:00:00 +0000

I backpacked northern Vietnam for about 3 weeks and spent 988 EUR.

As far as prices go, Vietnam is a bit cheaper than Bali, you can get small beer for less than 1 EUR, a coffee for less than 2 EUR and a traditional Pho Bo (beef soup) for about 2 EUR. Also, transporation is important in backpacking and on average I paid about 10 EUR for a 6h sleeper bus trip.

Month breaks

Mon, 16 Dec 2019 00:00:00 +0000

A very simple TradingView indicator that marks the start of every month with a vertical line. By default the vertical line is gray with 80% transparency but you can customize the style/color/transparency as you like.

Surviving Bali

Tue, 19 Nov 2019 00:00:00 +0000

I survived a month in Ubud, Bali, Indonesia with 2112 EUR :) I like the word survive but there is nothing to survive in Bali, especially in Ubud.

In-file navigation

Thu, 07 Nov 2019 00:00:00 +0000

Here are my Emacs in-file navigation goodies that I use on daily basis, splitted into 3 main categories:

Configuration management

Tue, 22 Oct 2019 00:00:00 +0000

Syncing configuration files across multiple machines is one thing but it is more important to track the config changes and figure out what went wrong when the system breaks. Here is my setup for both user's dotfiles and system's configuration files.

Leaving Apple, leaving Google

Tue, 08 Oct 2019 00:00:00 +0000

I've finally broken the corporation cage and I am Apple and Google-free.

From MacOS to Linux was an easy jump, bought new laptop, installed Arch Linux and done but phone is a different story and moving from Apple to Google is like going from bad to worst, it does not feel right.

Elliptic curves

Wed, 25 Sep 2019 00:00:00 +0000

The easiest way to understand Elliptic Curve (EC), point addition, scalar multiplication and trapdoor function; explained with simple graphs and animations.

Package management

Tue, 10 Sep 2019 00:00:00 +0000

I've finally put together a fast, reliable and non-intrusive way to install/query/clean pretty much any software package on the planet in 3 easy steps.

Zero-knowledge proofs

Mon, 26 Aug 2019 00:00:00 +0000

Zero-knowledge is a method to prove that you know a secret ``x`` (e.g. a password, private key, piece of knowledge, etc) without revealing that secret.

Zero-knowledge proofs

Mon, 26 Aug 2019 00:00:00 +0000

— layout: post title: "Zero-knowledge proofs" subtitle: Cryptography date: 2019-08-26 tags: ["cryptography", "zero-knowledge-proof", "math", "python", "zcash"] —

Password management

Mon, 12 Aug 2019 00:00:00 +0000

The very first problem you encounter when moving from one platform to another is password migration. Being an Apple user for so many years it was natural to leverage their tools and store my passwords in iCloud.

3 Days Project

Thu, 18 Jul 2019 00:00:00 +0000

Introducing 3 Days Project aka 3DP, a new Rails app generator template that adds and configures all the cool libraries/services that are needed to bootstrap new projects in no time.

Back to my first love

Fri, 05 Jul 2019 00:00:00 +0000

Here is my current system and my long journey in Linux, the operating system of a life time with all the good and the bad, on and offs.

EC-Schnorr

Tue, 25 Jun 2019 00:00:00 +0000

Overview

EC-Schnorr, as the name suggests, is a Schnorr-type digital signature scheme over elliptic curve, it's ECDSA's little sister and Schnorr's big brother implemented in the upcoming MuSig in Bitcoin.

Schnorr

Wed, 19 Jun 2019 00:00:00 +0000

Schnorr is another digital signature scheme known for its simplicity, no division, no inversion, just plain old multiplication. Here is my simple 16 lines implementation in Python.

Slices of Bitcoin

Fri, 31 May 2019 00:00:00 +0000

My second TradingView indicator in this series is Slices of Bitcoin, a very simple indicator that shows how many times a currency fits into Bitcoin. Here is the source code.

Ruby library for Deribit API

Fri, 03 May 2019 00:00:00 +0000

I just want to introduce the new open-source Ruby library for Deribit API.

Here is a short intro, for more information please check the source code repo and documentation.

From Jekyll to Hugo

Thu, 18 Apr 2019 00:00:00 +0000

Since nobody wants to embrace the dark side of Wordpress anymore, the easiest way (that I knew of) to bootstrap a personal website was Jekyll and Netlify. I am a huge advocate of getting things done fast, no fluff, just real stuff and this is what I did, but quite soon I realized that static Jekyll is not enough anymore and I needed to find new home.

ECDSA

Tue, 09 Apr 2019 00:00:00 +0000

Elliptic curve cryptography (ECC) and digital signature algorithm (ECDSA) are more complex than RSA or ElGamal but I will try my best to hide the hairy math and the implementation details.

ElGamal

Tue, 26 Mar 2019 00:00:00 +0000

ElGamal is a public key cryptosystem that is used in encryption , digital signature and homomorphic cryptography.

Here is my take in 12 lines of Python code:

RSA

Sat, 16 Mar 2019 00:00:00 +0000

RSA (Rivest-Shamir-Adleman) needs no introduction, it is well known and most used public-key cryptosystem that governs our digital lives.

Weekly/monthly close

Thu, 28 Feb 2019 00:00:00 +0000

I’ve decided to release a few personal indicators that I use in day by day trading and here is the first one: Weekly/Monthly close.

Open-sourcing Actihunt project

Thu, 14 Feb 2019 00:00:00 +0000

Project is NOT MAINTAINED/DEPLOYED anymore

I’ve decided to open-source an old and rusty project called Actihunt that sits there for more than 3 years.

Idiomatic Ruby library for BitMEX API

Mon, 28 Jan 2019 00:00:00 +0000

Fully featured, idiomatic Ruby library for BitMEX API. Support for both REST and Websocket APIs as described in API Overview.

Year 2018 in review

Wed, 02 Jan 2019 00:00:00 +0000

Back to annual review after 8 years, hopefully for real this time with the goods and the bads of 2018:

Introducing Cryptos-ruby project

Tue, 11 Dec 2018 00:00:00 +0000

I just want to announce the very first release [v0.0.3] of Cryptos-ruby project, a simple and very easy to use Ruby API to manipulate multiple crypto coins.

Bitcoin transaction by hand

Sun, 11 Nov 2018 00:00:00 +0000

This is Part 2 of ‘The hard way - Bitcoin’ series and I will start with ’the easy way’ section first because even this gets a bit complex, then will continue with the hard stuff, crafting a Bitcoin transaction from scratch using basic math and cryptography.

Bitcoin address

Tue, 09 Oct 2018 00:00:00 +0000

This article will present two ways of generating a Bitcoin address: the hard way using simple math and the easy way using an existing Bitcoin library.

Year 2010 in review (imported from old Blogspot)

Sun, 02 Jan 2011 00:00:00 +0000

Here we go … 2010:

Travel: visited 2 countries: UAE (Dubai, Abu Dhabi, Al Ain), France (Paris)
Trading: 22% profit in hedging account
eXtreme Sports: snowboarding - training mostly jumps and spinning
Workout/Sports: unfortunately not much here :(, shame, shame, shame
Professional: worked on my own on tennisaddiction.com, the other projects: zuppler.com and tvguide consulting go pretty well.
Family: moved into new house in Sep, all nice and good so far

C ya in 2012.

Year 2009 in review (imported from old Blogspot)

Sun, 03 Jan 2010 00:00:00 +0000

I am thinking to write down some things I’ve done in 2009, mostly for me as history. I remember I did it last year also but it was an offline doc and I lost it :). Stupid.

Mon, 01 Jan 0001 00:00:00 +0000

— title: "Elliptic curves" subtitle: Cryptography date: 2019-09-25 tags: ["cryptography", "elliptic-curve", "math", "sagemath", "python"] —

The easiest way to understand Elliptic Curve (EC), point addition, scalar multiplication and trapdoor function; explained with simple graphs and animations.

Mon, 01 Jan 0001 00:00:00 +0000

Device driver

Lifecycle of a device driver:

init
open
commands
- read/write
- ioctl
release
exit

  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/cdev.h>

  static char *world_name = "world";
  static int world_major = 6;
  static int world_minor = 0;

  struct world_device {
          char *whom;
	  size_t size;
	  struct cdev cdev;
  };

  void world_print(char* greet)
  {
	  printk(KERN_ALERT "%s, %s\n", greet, whom);
  }
  EXPORT_SYMBOL(world_print);

  struct file_operations world_fops = {
	  .owner = THIS_MODULE,
	  /* .read = world_read, */
	  /* .write = world_write, */
	  .open = world_open,
	  .release = world_release,
  };

  static int __init world_init(void)
  {
	  printk(KERN_ALERT "Init, World\n");

	  // register char device
	  devt = MKDEV(world_major, world_minor);
	  result = register_chrdev_region(devt, 0, world_name);
	  if (result < 0) {
		  printk(KERN_WARNING "world: can't get major %d\n", world_major);
		  return result;
	  }

	  // init/add char device
	  cdev_init(cdev, &world_fops);
	  cdev->owner = THIS_MODULE;
	  cdev->ops = &world_fops;
	  cdev_add(cdev, devt, 1);

	  return 0;
  }
  module_init(world_init);

  static void __exit world_exit(void)
  {
	  printk(KERN_ALERT "Exit, %s\n", whom);
  }
  module_exit(world_exit);

  MODULE_AUTHOR("Iulian Costan <kernel@costan.ro>");
  MODULE_DESCRIPTION("World char device driver");
  MODULE_LICENSE("Dual BSD/GPL");

Mon, 01 Jan 0001 00:00:00 +0000

— layout: post title: "Cryptography: Schnorr" date: 2019-06-19 tags: ["cryptography", "schnorr", "discrete-logarithm", "math", "sagemath"] —

Overview

"If you can't explain it simply, you don't understand it well enough" - Einstein

Schnorr is another digital signature scheme known for its simplicity, no division, no inversion, just plain old multiplication. Here is my simple 16 lines implementation in Python.

Mon, 01 Jan 0001 00:00:00 +0000

Startup

PROs:

implement basic features and release the MVP ASAP - as an old saying goes: "if you are not ashamed with your first release you are already too late"
setup initial users base and aim for 10x customer acquisition
roll-out new features and get into fail-fast feedback loop

CONs:

early optimizations/scale and security - the defaults provided by the framework is more than enough for initial bootstrapping stage
long scheduled releases - this kills the early feedback loop and might lead the project into wrong directions

About me

Mon, 01 Jan 0001 00:00:00 +0000

“I work for no one, I trust no one, I am a free man” - Julius Cornelius

FX

Mon, 01 Jan 0001 00:00:00 +0000

Inca trail

Mon, 01 Jan 0001 00:00:00 +0000

Gear

1. Shoes

| Type           | Brand      | Model       | Weight[g] | Required | Notes | TODO |
|----------------+------------+-------------+-----------+----------+-------+------|
| 1. Shoes       |            |             |      2310 |          |       |      |
| trekking boots | Garmont    | Rambler GTX |      1270 | yes      |       | FIX  |
| sport shoes    | LaSportiva |             |       690 |          |       |      |
| sandals        | Teva       | Universal   |       350 | yes      |       |      |

2. Clothing

2.1 Base layer - moisture wicking

| Type                  | Brand      | Model     | Weight[g] | Required | Notes | TODO |
|-----------------------+------------+-----------+-----------+----------+-------+------|
| 2.1 Base layer        |            |           |       495 |          |       |      |
| briefs                | Kalenji    |           |        84 | yes      | 2 pcs |      |
| boxers                |            |           |           | yes      | 2 pcs |      |
| midweight boxers      | Icebreaker | Anatomica |        64 |          |       |      |
| trekking socks        |            |           |           | yes      | 4 pcs |      |
| midweight socks       |            |           |           |          |       |      |
| t-shirt               |            |           |           | yes      | 2 pcs |      |
| midweight t-shirt     | Trespass   |           |       199 | yes      |       |      |
| long sleeve           |            |           |           | yes      | 2 pcs |      |
| midweight long sleeve | Mammut     |           |       148 | yes      |       |      |

2.2 Insulation layer - warmth

| Type                    | Brand | Model | Weight[g] | Required | Notes | TODO |
|-------------------------+-------+-------+-----------+----------+-------+------|
| 2.2 Insulation layer    |       |       |       388 |          |       |      |
| lightweight down jacket |       |       |           | yes      |       | BUY  |
| midweight fleece jacket | Milo  | Sella |       388 | yes      |       |      |

2.3 Outer layer - wind / rain

| Type              | Brand   | Model     | Weight[g] | Required | Notes | TODO |
|-------------------+---------+-----------+-----------+----------+-------+------|
| 2.3 Outer layer   |         |           |      1239 |          |       |      |
| convertible pants | Salomon | Elemental |       293 | yes      |       |      |
| windstop jacket   | Mammut  | Classic   |       486 | yes      |       |      |
| hardshell jacket  | Marmot  | Huntley   |       460 |          |       |      |
| rain jacket       | Quechua |           |           |          |       |      |

3. Accessories

| Type             | Brand  | Model  | Weight[g] | Required | Notes        | TODO |
|------------------+--------+--------+-----------+----------+--------------+------|
| 3. Accessories   |        |        |       456 |          |              |      |
| 3.1 Head         |        |        |       273 |          |              |      |
| hat              | LaFume |        |        58 | yes      | (with cover) |      |
| buff             |        |        |        95 |          |              |      |
| wool hat         |        |        |       120 | yes      | cold/sleep   |      |
| 3.2 Eyes         |        |        |        33 |          |              |      |
| sport sunglasses |        |        |        33 |          |              |      |
| 3.3 Face         |        |        |        78 |          |              |      |
| sunscreen        |        |        |        68 | yes      |              |      |
| lip balm         |        |        |        10 | yes      |              |      |
| 3.4 Hands        |        |        |        72 |          |              |      |
| fleece gloves    | Lowe   | Alpine |        72 |          | cold         |      |

4. Camping

| Type         | Brand         | Model      | Weight[g] | Required | Notes | TODO |
|--------------+---------------+------------+-----------+----------+-------+------|
| 4. Camping   |               |            |       794 |          |       |      |
| water bottle | Nalgene       | 1L         |       177 | yes      |       |      |
| thermos      | Primus        | 1L         |       524 |          |       |      |
| sleeping bag |               |            |           | yes      |       | RENT |
| headlamp     | Black Diamond | Revolt 350 |        93 | yes      |       |      |

5. Trekking

| Type           | Brand  | Model       | Weight[g] | Required | Notes | TODO |
|----------------+--------+-------------+-----------+----------+-------+------|
| 5. Trekking    |        |             |      2100 |          |       |      |
| backpack       | Osprey | Stratos 24L |      2100 | yes      |       |      |
| trekking poles |        |             |           |          |       | RENT |

6. Toiletries

| Type            | Brand      | Model | Weight[g] | Required | Notes         | TODO |
|-----------------+------------+-------+-----------+----------+---------------+------|
| 6. Toiletries   |            |       |       190 |          |               |      |
| toilet bag      | Deuter     |       |       190 | yes      |               |      |
| small towel     |            |       |           | yes      |               |      |
| small soap      |            |       |           | yes      |               |      |
| deodorant stick |            |       |           | yes      |               |      |
| toilet paper    |            |       |           | yes      | 1 roll/ 2 pax |      |
| wet wipes       |            |       |           | yes      |               |      |
| tooth brush     | Parodontax |       |           | yes      |               |      |
| tooth paste     | Sensodyne  |       |           | yes      |               |      |
| mouth water     | Listerine  |       |           | yes      |               |      |
| dental floss    |            |       |           | yes      |               |      |

7. Tech

| Type            | Brand   | Model            | Weight[g] | Required | Notes      | TODO |
|-----------------+---------+------------------+-----------+----------+------------+------|
| 7. Tech         |         |                  |      1084 |          |            |      |
| sport watch     | Garmin  | Forerunner 920XT |       186 |          | +usb cable |      |
| satellite phone | Thuraya | XT Pro           |       426 |          | +usb cable |      |
| cell phone      | OnePlus | T5               |       257 | yes      | +usb cable |      |
| power bank      | Asus    |                  |       215 |          |            |      |
| power adapter   |         |                  |           | yes      |            |      |

8. Misc

| Type             | Brand     | Model    | Weight[g] | Required | Notes | TODO |
|------------------|-----------|----------|-----------|----------|-------|------|
| 8. Misc          |           |          | 204       |          |       |      |
| first-aid kit    |           |          |           | yes      |       |      |
| drugs/medication |           |          |           |          |       |      |
| binocular        | Konus     |          | 161       |          |       |      |
| compass          | Trekmates | Explorer | 43        |          |       |      |

Options

Mon, 01 Jan 0001 00:00:00 +0000