Eta (letter) Updated 2025-07-16
gothinkster/realworld Updated 2025-07-16
Ahh, you can't have new ideas anymore!
Basically puts together every backend with Front-end web framework to create the exact same website.
The reference live demo can be found at: demo.realworld.io/#/ It is based on Angular.js as it links to: github.com/gothinkster/angularjs-realworld-example-app TODO backend?
There are however also live demos of other frontends, e.g.:Note that all those frontends communicate with the same backend.
- React: react-redux.realworld.io. But note that tag addition at post creation is broken there as of March 2021, but not on master: github.com/gothinkster/react-redux-realworld-example-app/issues/151#issuecomment-808417846 so they forgot to update the live server.
- Vue.js: vue-vuex-realworld.netlify.app
As of 2021 Devs are seemed a bit too focused on monetizing the project through their "how to use this project" premium tutorial, and documentation could be better: just getting the hello world of the most popular backend with the most popular frontend is not easy... come on.
github.com/gothinkster/realworld/issues/578 asks for community support, as devs have moved on since unfortunately.
Remember:
- by default, the frontends hardcode the upstream public data API:
https://conduit.productionready.io/apiso you have to hack their code to match the port of the backend. And each backend can have a different port. - when you switch between backends, you must first manually clear client-side storage cookies/local new run will fail due to authentication issues!
Important missing things from the minimum base app:
- server-side rendering:
- github.com/arrlancore/nextjs-ssr-real-world-app-example. As advertised, that global instance does render with JavaScript disabled! Proposed for upstream at: github.com/gothinkster/realworld/issues/423
- github.com/gothinkster/realworld/issues/266
- no javaScript bi-directional communication library built-in... come on: github.com/gothinkster/realworld/issues/107
- email notifications however as tested on the live demo: demo.realworld.io/#/
- error handling is broken/missing/inconsistent across apps
First you should the most popular backend/frontend combination running, which is the most likely to be working. We managed to run on Ubuntu 20.10, React + Node.js Express.js as described at github.com/gothinkster/node-express-realworld-example-app/pull/116:Then just:on both server and client, and then visit the client URL: localhost:4100/
- github.com/cirosantilli/node-express-realworld-example-app/tree/mongo4 which has a simple patch on top of github.com/gothinkster/node-express-realworld-example-app/tree/ba04b70c31af81ca7935096740a6e083563b3a4a for MongoDB 4 supportThis requires you to first install MongoDB on Ubuntu and ensure you can login to it from the command line.
- github.com/gothinkster/react-redux-realworld-example-app/tree/9186292054dc37567e707602a15a0884d6bdae35 patched to use the correct server host/port
localhost:3000:diff --git a/src/agent.js b/src/agent.js index adfbd72..e3cdc7f 100644 --- a/src/agent.js +++ b/src/agent.js @@ -3,7 +3,7 @@ import _superagent from 'superagent'; const superagent = superagentPromise(_superagent, global.Promise); -const API_ROOT = 'https://conduit.productionready.io/api'; +const API_ROOT = 'http://localhost:3030/api'; const encode = encodeURIComponent; const responseBody = res => res.body;
npm install
npm startYou have to hit the Enter key to add tags, it's terrible: github.com/gothinkster/react-redux-realworld-example-app/issues/151#issuecomment-808417846
One cool thing is that the main repo has unified backend API tests:so the per-repository tests are basically useless, and that single test can test everything for any backend! There is no frontend testing however: github.com/gothinkster/realworld/issues/269 so newb.
git clone https://github.com/gothinkster/realworld
cd realworld
git checkout e7adc6b06b459e578d7d4a6738c1c050598ba431
cd api
APIURL=http://localhost:3000/api USERNAME="u$(date +%s)" ./run-api-tests.sh The CSS of Ciro Santilli's website looks broken Updated 2025-07-16
That which does not exist, cannot be broken.
And of course:
Continuous spectrum (functional analysis) Updated 2025-07-16
Unlike the simple case of a matrix, in infinite dimensional vector spaces, the spectrum may be continuous.
The quintessential example of that is the spectrum of the position operator in quantum mechanics, in which any real number is a possible eigenvalue, since the particle may be found in any position. The associated eigenvectors are the corresponding Dirac delta functions.
Controlled quantum gate Updated 2025-07-16
Controlled quantum gates are gates that have two types of input qubits:These gates can be understood as doing a certain unitary operation only if the control qubits are enabled or disabled.
- control qubits
- operand qubits (terminology made up by Ciro Santilli just now)
Generic controlled quantum gate symbol
. Source. When the operand has a conventional symbol, e.g. the Figure "Quantum NOT gate symbol" for the quantum NOT gate to form the CNOT gate, that symbol is used in the operand instead.
Why is COVID-19 so serious in some people but not in others? Updated 2025-07-16
There are a few possibilities:
- genetics
- bibliography:
- www.science.org/doi/10.1126/scitranslmed.abj7521 Identification of driver genes for critical forms of COVID-19 in a deeply phenotyped young patient cohort by Carapito et al. (2021)
- bibliography:
- state of the immune system based on disease history
- age
csvtool Updated 2025-07-16
A compiled executable under
/usr/bin/csvtool, has an Ubuntu 23.04 package: manpages.ubuntu.com/manpages/lunar/en/man1/csvtool.1.htmlThere seems to be no sane filtering mechanism however: stackoverflow.com/questions/46540752/using-csvtool-call-to-filter-csv-in-bash
Electronvolt Updated 2025-07-16
Filter (signal processing) Updated 2025-07-16
Homeobox gene Updated 2025-07-16
Intermediate filaments Updated 2025-07-16
Linux Unified Key Setup Updated 2025-07-16
Pythagorean triple Updated 2025-07-16
Quantum Mechanics for Engineers by Leon van Dommelen (2011) Updated 2025-07-16
Looks very impressive! Last update marked 2011 as of 2020.
Goes up to "A.15 quantum field theory in a Nanoshell", Ciro have to review it to see if there's anything worthwhile in that section.
Personal page says he retired as of 2020: www.eng.fsu.edu/~dommelen/ But hopefully he has more time for these notes!
And he appears to have his own lightweight markup language that transpiles to LaTeX called l2h: www.eng.fsu.edu/~dommelen/l2h/
Tearjerker Updated 2025-07-16
Why is COVID-19 more serious than the flu? Updated 2025-07-16
Firmware Updated 2025-07-16
Fujitsu Updated 2025-07-16
The japanese name literally means:
- 富士 fushi, from Mount Fuji, which itself has unknown origin
- 通 tong: telecommunications
Positive definite matrix Updated 2025-07-16
The dot product is a positive definite matrix, and so we see that those will have an important link to familiar geometry.
A quote by Ciro's Teacher R.:
Sometimes, even if our end goals are too far from reality, the side effects of trying to reach them can have meaningful impact.
If the goals are not ambitious enough, you risk not even having useful side effects so show in the end!
By doing the prerequisites of the impossible goal you desire, maybe the next generation will be able to achieve it.
This is basically why Ciro Santilli has contributed to Stack Overflow, which has happened while was doing his overly ambitious projects and notice that all kinds of basic pre-requisites were not well explained anywhere.
This is especially effective when you use backward design, because then you will go "down the dependency graph of prerequisites" and smoothen out any particularly inefficient points that you come across.
There are of course countless examples of such events:
- youtu.be/qrDZhAxpKrQ?t=174 Blitzscaling 11: Patrick Collison on Hiring at Stripe and the Role of a Product-Focused CEO by Greylock (2015)
The danger of this approach is of course spending too much time on stuff that will not be done enough times to be worth it, as highlighted by several xkcds:
xkcd 1319: Automation
. Source. There are unlisted articles, also show them or only show them.



