Planet FSCI

April 01, 2025

• Bhavani Shankar Four stories for honing mental toughness

  If you suffer from difficult emotions like me, this post can help. After exploring pragmatic beliefs, I long to share these four stories. These tales are a refuge during turbulent times. So, they are close to my heart. Most of these are extracted from discourses given by the Buddha.

  Ruminations of a dying king

  A king goes hunting in a forest and is shot with a poisoned arrow. His men rush him to the nearest village. The herbal doctor lays him down on a bed and starts dressing up his wound and offers an antidote. The king refuses the medicine and starts saying

  "I can't take the medicine until I know who shot me and why. Is he an enemy from a neighboring kingdom? What metal and wood is the arrow made of? Why did he shoot me there but not deeper in the jungle? ..."

  The doctor replies "If you don't take the medicine, not only will your questions remain unanswered, you will die".

  In the face of hardships that are beyond our control, we tend to sit in a corner and cry. Drowned in victim mindset, we ruminate over questions that lead nowhere — just like the king. Let go, and take the medicine.

  Two arrows of hurt

  Being hit by two arrows hurts much worse than just one. Buddha said the first arrow is what life throws at us — including pain, diseases, death of loved ones, disagreements, famine, and unfulfilled desires etc. This first arrow is unavoidable. It's a law of nature that we will be shot every once in a while.

  The 2nd arrow is us lamenting our fate and yearning for things to be different. This arrow hurts worse and lasts much longer. It is self inflicted — a conditioned response of our mind. Buddha says we can train our mind to diminish its effects until it no longer exists. Therefore, accept everything life gives us.

  Cow with a rare disease

  Imagine a cow that has no skin due to a rare genetic condition. As it grazes along the banks of a river, leeches, maggots, insects, and all kinds of parasites grasp onto its bare flesh and start feeding on it.

  Buddha says an untrained mind is like this cow. All kinds of filth gets into our minds through our senses like billboards, notifications, ads, gossip, criticism and cravings etc and rock it like a boat in a storm. This causes great suffering. Don't consume mindlessly. Use mindfulness as a sentinel that guards our senses and stills the mind.

  An absurdly tough ankle noose

  An elephant was captured when it was a baby. To keep it from escaping, the captor tied one of its ankles to a banana tree. The elephant struggled with all of its might to get loose. It kept trying for hours and realized it was of no use. Years passed by and the elephant grew into an adult. Every day the human would take the elephant for logging and at the end of the day, tie its ankle to the same banana tree with the same rope. The elephant can now easily break the rope or uproot the tree. But, it never tried to escape — not even once.

  Just like the elephant, we are carrying mountains of baggage — false beliefs and habits that limit us. Maybe something as simple as believing we are bad at math, social skills, and sports or being a hoarder due to growing up in poverty or suffering from a paralyzing fear of heights. We can recognize and unlearn everything. Meticulously question each belief, study your behavior, and cultivate an open mind.

---

March 29, 2025

• Bhavani Shankar A simple setup for distraction free writing

  I am at peace after purging Instagram, WhatsApp, and YouTube. Life is slower and incredibly mindful. I am settling comfortably into books, the small web and crafting this blog.

  Chosen tools for writing

  Worn down by configuration fatigue induced by abusing Emacs, Vim, and window managers for years, I am in search for simple tools that get things done. They have to be:

  1. Zero config - should have sane defaults and batteries included.
  2. Offline and privacy friendly - should not transmit my prose to privacy nightmares like Grammarly or OpenAI.
  3. Lightweight, fast - should run on tiny devices and give real-time feedback. LanguageTool (Java) and Electron based bloatware are out.

  Writing is fun in Helix

  Seduced by its minimalism, speed, and modal editing approach, I switched to the post-modern text editor - Helix. Here are the other packages I utilize for writing:

  1. Harper - a tiny grammar and spell checker
  2. Prettier - formats text and code snippets
  3. Zola - for generating websites and taking notes.

  To integrate these tools into helix, and enable text wrapping for prose, append the following into ~/.config/helix/languages.toml.

  # Check grammar with harper
  [language-server.harper-ls]
  command = "harper-ls"
  args = ["--stdio"]
  
  [[language]]
  name = "markdown"
  language-servers = [
    { name = "harper-ls" }
  ]
  
  # Enable soft wrapping of text
  soft-wrap.enable = true
  text-width = 80
  soft-wrap.wrap-at-text-width = true
  
  # Format markdown and code snippets with prettier
  formatter = { command = 'prettierd', args = [
    "--parser",
    "markdown",
    "--prose-wrap",
    "never",
  ] }
  auto-format = true
  

  Zola for note taking

  You may have noticed that some posts like "why start another blog?" link back to this page. That's because Zola can automatically show backlinks - making it a powerful knowledge management system like Obsidian. We just have to tweak its config.toml.

  bottom_footnotes = true # adds footnote backreference
  

  Use the internal linking format (that begins with @). Then, we can use this snippet in the footer template to display all backlinks.

  {% if page.backlinks %}
  <div class="backlinks">
  <h4>Links to this page</h4>
  <div>
  {% for bl in page.backlinks %}
    <div>
      <a href={{ bl.permalink }}>{{ bl.title }}</a>
    </div>
  {% endfor %}
  </div>
  </div>
  {% endif %}
  

  Bonus: clean reading without ads or spam

  I don't use my email to subscribe to newsletters. Now, I am all into RSS feeds and I don't take websites without it seriously. There is plenty of quality content and feeds to discover on Feedle and in the Fediverse. My favorite rss readers are:

  • Capyreader (Android)
  • Rssguard (Linux, Windows, MacOS)
  • Feedbro (Addon for Firefox, Chrome, and edge.)

  In this way, you can write freely and avoid brain damaging ads and social media.

---

March 28, 2025

• Thejeshgn GN Weekly Notes 13/2025

  It's iftar time on Mosque Road in Bangalore. I went out for dinner with friends on Sunday evening. This time, we chose a restaurant instead of street food. Sharief Bhai had a special iftar meal for four. Even though it was for four people, it was a lot. We ate a lot and packed some food for home.

  

  • We spent Saturday at Boond, just outside Sarjapur. The road to Sarjapur is hell, but Boondh is quite calming. It rained pretty heavily on our back, which was nice as it lowered the temperatures. I love Bangalore's summer rains.
  • On Sunday, I was at MisInfoCon to give a talk. I missed it because the organizers sent the wrong schedule. I am not blaming them; I should have checked the website and not just depended on emails. Organizers are constantly under pressure and tend to make mistakes (from my experience as an organizer). But it was fun to attend some talks, meet people, etc.
  • Updates on this website: I updated the contact page to include chat as an option. I also updated the Keep Me Informed section of NMG to include details about the Friends of NMG.
  • I canceled my credit card last week because someone used it to do a fraudulent transaction at FARMER BOYS - DIAMOND 909-444-6800 CA. This is the first time it has happened to me. My card issuer calls me every time there is a suspicious transaction. In the last 10 years, it has never been useful. This time, I got a call in the middle of the night ( in India). Usually, I would ignore it, but this time, I picked up, and for sure, it was a fraudulent transaction. So, I canceled my current one, requested a new credit card, and raised a dispute. All this is to say that a new card has arrived. I haven't activated it yet. I am curious how the dispute/chargeback will be handled. Apparently, it takes time.
  • I am in Mumbai. It was a quick work trip on Thursday and Friday. Some interesting things are planned. Hopefully, I get to write about them someday. I did contribute to beaconDB during this trip. I also wrote a short post about it.
  • If you plan to build a CMS or Website, try Wagtail, especially if you are into a boring yet modern Python web stack. I have had a positive experience building a flexible CMS-based website with it. It is very developer-friendly. It has good REST and GraphQL APIs. Their support for a headless version is coming along well. The content management UI is very user-friendly.

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March 27, 2025

• Thejeshgn GN Contributing to beaconDB

  beaconDB is a public-domain wireless geolocation database. It replaces Mozilla Location Service, which, of course, was shut down in 2024. I used to contribute to MLS very regularly. I think I was on their contribution leader-board, too. Anyway, recently, I started contributing to it. Like I have written in WN 11/2025, I promised to contribute one Lakh unique beacons (wifi+cell+ble) to keep my competitive mind going.  

  

  beaconDB currently has a free API to access the resolved location (follows ichnaea's geolocate) if you send them the details of beacons around you with their power. Multiple beacons, with their location and power, are used to triangulate your location. Of course, their accuracy depends on the data and won't be as accurate as GPS. Yet, this could be useful when a real GPS can't be used. For example

  • Indoors
  • Places where GPS signals are weak or there is no direct line of sight
  • Devices that don't have GPSes like laptops or cheap controllers, etc

  Contributing is easy. You can install one of the suggested apps and configure the app to upload the collected data to BeaconDB. I used NeoStumbler, which is an updated version of MozStumbler. When you are ready, click the start scanning button, walk around and once done, stop it and send the reports. Easy. To use the geolocation resolver, you can configure your laptop or microG/Andoid to use beaconDB instead of the default ones.

  There are other fun ways to use this API, too. For example, in personal projects, you can use an ESP32 to log timestamps with nearby beacons and their signal strength while traveling. Once back home, query a beacon database using this data to estimate GPS locations. You can do this on a laptop, too.

  

  

  I hope I got your interested in contributing the data and/or using the geolocation APIs. While doing that, have fun.

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March 26, 2025

• Bhavani Shankar CSS tips: Gentle image filters for dark mode

  Viewing images in dark mode can hurt your eyes. This is because, while text is optimised for reading in low light reading automatically, images are often neglected. So, a bright image in the middle of prose causes discomfort. I mulled over this issue. Here are some solutions I came up with:

  Illustrations

  Diagrams, illustrations, comics, cartoons etc whose colors aren't constrained by reality fall in this category. We can just invert them and reduce some brightness.

  @media (prefers-color-scheme: dark) {
    .image-invertible {
      filter: invert(1) brightness(0.67);
    }
  }
  

  See it in action in my recursive universes post. Try toggling the theme using the button at the top and observe how the diagrams change.

  Photos

  Images captured by a camera look terrible when inverted. Reducing the brightness is the only thing we can do.

  @media (prefers-color-scheme: dark) {
    .image-non-invertible {
      filter: brightness(0.67);
    }
  }
  

  I used this method in my about me page. With tiny tweaks like this one, we can make huge leaps towards delighting our readers.

---

March 21, 2025

• Thejeshgn GN Weekly Notes 12/2025

  We returned from Langkawi on Wednesday after a week-long vacation. It was a good trip. I had nearly a thousand unread emails, both work and personal when we returned. Around 80% of them are non-critical - newsletters, alerts from GitHub, issue trackers, etc. But I believe in inbox zero, so I had to read the 20% and mark the rest as read. That's a lot of work. It took me almost a day.

  

  • Also, this vacation was good for my neck, even though it wasn't planned for that. I see and recognize how being away from the screens has helped recovery. Pain intensity has reduced considerably; it is at zero while wearing a cervical collar and very low when I am not wearing it. I am still wearing a collar to help me recover. I have yet to start on neck exercises, which I plan to do next week after the next consultation with the doctor.
  • It's Echo's gotcha week. I can't believe it's been five years. He is a fantastic dog and an amazing elder brother to Uma and Pathu. Anju baked a cake to celebrate for both Echo📷 and Pathu📷. It took 30 seconds for Echo to finish it.
  • I have shut down my Mastodon instance and go back to social.lol/@thej
  • NMG application for 2025 is closed. We have received 100+ applications for 4.5 Lakh rupees this year. In terms of grant money, this is our biggest year. I will start going through the applications on Monday.
  • An interesting thing I noticed this week on Grammarly is that when it fails (for whatever reason), Instead of showing an error message, it defaults to telling you everything is correct—a misleading false positive.
  • AWS Bedrock (LLM, etc.) serverless APIs seem like a good place to access running LLM models, especially if you are experimenting and don't have enough money to run a dedicated GPU-based machine to run Ollama+Models. Sadly enough, it doesn't provide OpenAI-compatible API (now defacto API standard for chatting with LLMs on the web). However, Amazon provides an OpenAI-compatible RESTful API translator as a docker image; you can run it or use litellm proxy. Then, add Bedrock to your project or your Open WebUI instance.
  • LLMs are evolving fast, so I'm trying many tools, formats, and standards. A few have stood out despite the churn—like Ollama, Open WebUI, lilellm proxy, and the OpenAI API format. For me, all the magic happens behind the APIs or downstream. I love standard interfaces, whether it's UI or API. What's the AI toolset that has stayed with you?

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March 20, 2025

• Thejeshgn GN Shutting down my Mastodon instance

  I was using Masto.host hosted Mastodon instance at social.thej.in for a year (Week 07/2024). I am shutting it down for now and returning to social.lol/@thej account.

  There are a couple of reasons for doing this.

  1. Cost: It started at $6/pm, and now I pay $19/pm + taxes. Running a federated social media platform just for yourself (It keeps copies on your server just for you) costs more. It is a waste of energy compared to running it for a bigger group or community. I wish there were a society or NPO that would run this for us for a fee, of course.
  2. Usage: I am using less and less social media; also, what I post on social media has value in a time-bound way and doesn't require archival as such. Anything important goes on this blog or thej.in
  3. Community: I like omg.lol/social.lol community. I would like to continue to support and participate. They are very affordable. And have a very friendly community.

  So what changes

  1. For most of my followers, nothing should change. Mastodon has good followers/following migration. So, for all of you, it should work as it is.
  2. I wish there were a way to map individual accounts on any server to a DNS name in Mastodon. Hopefully, one day, we will have it. As of now, I have used webfinger discovery to forward the account. So @thej@social.thej.in should reach @thej@social.lol. It uses a simple static site for this.
  3. There will be link rots to individual post URLs, mainly on Twitter, which, frankly speaking, I don't care.
  4. Anything significant will be backed up and archived on thej.in

  

  Sorry about all the confusion. It's part of a hosting experiment, I guess.

  Thank you.

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---

• Bhavani Shankar Strange paradoxes of recursive universes

  I couldn't believe my own answer to this puzzle. After thinking hard to disprove it, I finally understood it.

  Imagine being in a large box with your box lying on the floor beside you. Your box contains a smaller copy of you and a smaller box inside and so on ad infinitum. You reach your hand into your box and pull out the smaller box. As you do this, you see a bigger hand coming from above and taking your box. Note that all the infinite copies of you have done the same. The boxes and the hands can pass through each other. So, there are no collisions.

  Then, you put the box in your hand on the floor where the old box was. Where is your box now?

  

  In this picture, your box is colored. The box that you pulled out is shown with a thick border. Dots indicate that the pattern continues forever.

  The solution

  As insane as this sounds, your box is now infinitely far away.

  Let's derive the answer. To keep track, we will assign numbers to the boxes. Your box is 0. The boxes inside will be labeled 1, 2, 3, 4, .... You are inside the box -1. We label the outer boxes -2, -3, -4, .... Here's what it looks like:

  

  Let's use a simple notation to indicate that we can grab box 2 through box 1 (or that 2 is inside 1)

  [1] -> [2]

  Then, the original configuration of the boxes looks like the following.

  ... [-2] -> [-1] -> [0] -> [1] -> [2] -> [3] -> [4] -> [5] ...

  You pulled box 1 into -1, 0 was pulled into -2, -1 was pulled into -3, -2 was pulled into -4 and so on. We can observe the emergence of two chains - one for odd numbers and one for even numbers.

  ... [-5] -> [-3] -> [-1] -> [1] -> [3] -> [5] ... (odd numbers)

  ... [-6] -> [-4] -> [-2] -> [0] -> [2] -> [4] ... (even numbers)

  And this is the final result. From your perspective, the even numbered boxes including your box are nowhere to be seen!

  

  We are left with a rather disturbing mystery. Are half of the boxes really gone and when exactly? Can't we just reverse our actions to get them back?

  Resolving the mystery

  Being a recursive arrangement of boxes within boxes, the connections between boxes were constrained. To reach an inner box, you have to go through the boxes in the middle. So, if one of the boxes in the middle cannot be reached, you lose access to all the boxes inside it - exactly what has happened here. The moment you placed the smaller box on the floor and let it go, you ended up creating two parallel universes. By going inside or outside a box you cannot jump into the other universe.

  This concept is often encountered in data structures like linked lists. A linked list is a chain of nodes. Each node contains a number and the address of the next number. If you remember the starting node, you can keep jumping to the next node's address and see all the numbers. But, if you cut the linked list in the middle or take alternate nodes and link them together into 2 linked lists (like above), you cannot reach all nodes starting from any one node.

  Simpler example

  Sometimes it helps to look at a smaller (finite) example. Imagine there are just 8 boxes.

  [-4] -> [-3] -> [-2] -> [-1] -> [0] -> [1] -> [2] -> [3]

  The first 2 boxes (-4, -3) are not moved. Both -2 and -3 will be inside -4. -2 has all the even boxes inside and -3 has all the odd boxes inside.

  [-4] -> [-2]  -> [0]  -> [2]
    ↓  
  [-3] -> [-1] -> [1] -> [3]
  

  Aha! The largest box still connects the odd and even numbered boxes. But, that connection was pushed away to infinity in our puzzle.

  This is a modified version of a puzzle created by Michael Savage.

---

March 18, 2025

• Thejeshgn GN Langkawi

  We wanted a birthday trip like last year. I also wanted it to be less buzzy and toddler-friendly. So I started searching for a holiday place within 8 hours of travel time and a single hop. Langkawi turned up in the search results. I didn't know about it, but the more I read, the more I liked it. It seemed like a perfect place for us.

  Indigo had the perfect flight (3 hr and 20 mins), though at odd hours. We reached Langkawi at 10:30 AM. The small airport reminded me of HAL airport. We caught a Grab taxi to our stay at Frangipani Langkawi Resort. My first impression of the island was that it was small, silent, traffic-free, and had friendly people. Apparently, you can drive a self-drive car or bike with an Indian license. I saw lots of boards advertising car and bike rentals. For now, we decided to take Grab everywhere. But looking at the traffic, I could see myself driving.

  For now, you don't need a visa to visit Langkawi (Malaysia). You just need to fill out the arrival card before landing in Langkawi.

  Frangipani Langkawi Beach Resort

  We planned a week-long vacation, so we wouldn’t have to do multiple things in one day, allowing Uma enough rest. We booked and stayed at Frangipani for the whole week. If you are experimental, you can split your stay across multiple parts of Langkawi. But I found staying in one place useful, especially with a toddler. Frangipani is a beach resort close to Cenang Beach, with its own beach and beach restaurant. You can spend your day in the water or sitting by the restaurant. It's also a good place to watch the sunset.

  

  

  

  

  

  

  

  The cottage we got was big enough, though it didn’t come with a kitchenette. The internet/WiFi across the resort was surprisingly stable and seamless. The staff was helpful and generous. There are grocery stores, car/bike rental places, and restaurants nearby, making it convenient.

  Langkawi Wild Park

  I didn’t think Uma would enjoy it, but she loved it. It was a great success. We did too.

  

  

  

  

  

  Langkawi Underwater World

  Uma didn’t enjoy this as much as I thought she would. Maybe because she still can’t differentiate between one type of fish and another. A slightly older kid would have loved it.

  

  Dinner at Rimba at Ambong Pool Villas

  We had most of our breakfasts (included in the room cost) and dinners at the resort. But one day, we went out for dinner at Rimba at Ambong Pool Villas. The restaurant has amazing sunset views. The service was impeccable—attentive without being intrusive. The staff genuinely cared about our experience. The food was great, and we loved every dish. They even dropped us back at our resort. It was a memorable evening. Thank you, Prem. I gave them five stars.

  Mangrove Tour

  We mostly did this for ourselves. We wanted to see the geoparks and the mangroves. We took an organized tour. It was comfortable, covering the popular itinerary. However, I would have loved to spend more time just watching the mangrove forests.

  

  

  

  

  

  

  

  Langkawi Night Market

  Langkawi has night food markets every day in different parts of the city. They sell a variety of street food at very affordable prices. We went to one, packed food, and ate a lot.

  

  

  

  

  

  SkyBridge - SkyCab

  A standard visit to SkyCab and SkyBridge. Almost all tourists go there. The views are good. The tickets are quite expensive, but I think it’s okay for one visit.

  

  

  

  Citizen Science

  I couldn’t do much OSM this time. But I did report a couple of observations to iNaturalist and GlobeAtNight. I also submitted many reports to BeaconDB using NeoStumbler. I will write about BeaconDB in a separate post, but if you're interested, check out their website or read about the now-shutdown Mozilla Location Services, which it replaces.

  

  

  End Note

  We couldn’t go on a hike; it was too hot, and with a toddler who can’t walk much, it would have been difficult. We also missed visiting other geoparks in Langkawi. Maybe we can come here again in a different season, drive around, hike, and watch mangroves. We loved how we spent this week. I’m sure we would love to be here again.

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• Bhavani Shankar Sudoku solver in 100 lines of Rust

  Sudoku is an addictive number placement puzzle that is logic-based. To win, you should fill the missing cells such that all rows, columns and each of the nine 3x3 boxes contain all numbers from 1 to 9. A well-posed Sudoku has only one solution.

  

  After conquering basic algorithms, a Sudoku solver feels like a rite of passage to be a good coder. So, let's write a program that can solve any Sudoku puzzle in less than a second, starting from scratch.

  Algorithm

  To solve any problem, we should begin by designing an algorithm. Let's see -

  1. Check if the Sudoku puzzle is valid.

  2. Find an empty cell and guess a number.

  3. Continue with (1) until either:

     a. No empty cells are left - we found a solution!

     b. We cannot proceed - We made wrong guesses. Then, we should step back and try and continue (1) with a different guess.

  This backtracking algorithm will enumerate all solutions. If you are familiar with graphs, you will notice it is identical to depth-first search.

  

  Each circle is an intermediate solution. You jump to the bottom circles by making a valid guess (arrow) and when you reached the bottom, you take a step back and explore other possibilities.

  Encoding

  To achieve a compact representation, we can write down a Sudoku row by row as an array of numbers. Empty cells are indicated with 0. Then, the above puzzle becomes:

  000000005000075060715000002074031006100706003600520970300000859020980000400000000

  Validating a region

  With this representation in mind, we can begin by writing a check for all Sudoku constraints - all rows, columns and 3x3 boxes should contain 1 to 9 exactly once. Let's call each one of them regions. A region can be one particular row or a column or a box.

  fn is_valid_region(region: [u8; 9]) -> bool {
      let mut seen = [false; 10];
  
      for n in region {
          if n != 0 && seen[n as usize] {
              return false;
          }
          seen[n as usize] = true;
      }
  
      true
  }
  

  The function is_valid_region checks if the numbers 1-9 occur only once.

  Extracting regions

  Fetching the nth row of a Sudoku is straightforward. In our representation, the 1st row is 0, 1, 2, ..., 8. The 2nd row is 9, 10, 11, ..., 17 and so on. So, the nth row is:

  With a similar approach, we can deduce the patterns for nth column and the nth box. To keep the code simple, I hard coded the 1st box and the offsets to get the other boxes.

     // Get nth row of a sudoku
     fn get_row(sudoku: [u8; 81], row_index: usize) -> [u8; 9] {
         let mut row = [0; 9];
         for i in 0..9 {
             row[i] = sudoku[i + row_index * 9];
         }
         row
     }
       // Get nth column of a sudoku
     fn get_column(sudoku: [u8; 81], column_index: usize) -> [u8; 9] {
         let mut column = [0; 9];
         for i in 0..9 {
             column[i] = sudoku[i * 9 + column_index];
         }
         column
     }
       // Get nth box of a sudoku
     fn get_box(sudoku: [u8; 81], box_index: usize) -> [u8; 9] {
         let mut box_region = [0; 9];
         let first_box = [0, 1, 2, 9, 10, 11, 18, 19, 20];
         let box_offsets = [
             0,
             3,
             6,
             9 * 3,
             9 * 3 + 3,
             9 * 3 + 6,
             9 * 6,
             9 * 6 + 3,
             9 * 6 + 6,
         ];
      
         for i in 0..9 {
             box_region[i] = sudoku[first_box[i] + box_offsets[box_index]];
         }
         box_region
     }
  

  Validating Sudoku

  To check if a Sudoku is valid, we just need to extract all 27 regions and verify that they are consistent.

  // Returns true if a sudoku is valid.
  fn is_valid_sudoku(sudoku: [u8; 81]) -> bool {
      for i in 0..9 {
          if !(is_valid_unit(get_row(sudoku, i))
              && is_valid_unit(get_column(sudoku, i))
              && is_valid_unit(get_box(sudoku, i)))
          {
              return false;
          }
      }
      true
  }
  

  Solving

  The backtracking algorithm that we designed looks like this in Rust:

  /// Recursively enumerates all solutions of a sudoku puzzle
  pub fn solve_sudoku(sudoku: [u8; 81]) -> Vec<[u8; 81]> {
      let mut solutions = Vec::new();
   
      fn solver(solution: [u8; 81], solutions: &mut Vec<[u8; 81]>) {
          let mut empty_cell_found = false;
       
          for i in 0..81 {
              if solution[i] == 0 {
                  empty_cell_found = true;
               
                  for n in 1..10 {
                      let mut new_solution = solution;
                      new_solution[i] = n;
                      if is_valid_sudoku(new_solution) {
                          solver(new_solution, solutions);
                      }
                  }
                  break;
              }
          }
       
          if !empty_cell_found {
              solutions.push(solution);
          }
      }
   
      solver(sudoku, &mut solutions);
      solutions
  }
  

  We find an empty cell, make a valid guess and call solver recursively. We keep exploring deeper and deeper until we cannot proceed further. If all the cells are filled up, then it's a solution. We add it to our list. We continue searching the remaining paths in this graph.

  This worked beautifully. It printed out the solution to the above puzzle in 0.0s.

  534678912672195348198342567859761423426853791713924856961537284287419635345286179

  Here's another example:

  let sudoku = [
      6, 4, 5, 9, 0, 0, 0, 0, 0,
      0, 7, 3, 1, 0, 0, 0, 5, 0,
      2, 0, 0, 0, 5, 0, 0, 0, 0,
      5, 9, 0, 0, 3, 7, 6, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 4, 5, 8, 0, 0, 3, 9,
      0, 0, 0, 0, 7, 0, 0, 0, 3,
      0, 3, 0, 0, 0, 4, 1, 9, 0,
      0, 0, 0, 0, 0, 1, 8, 2, 7,
  ];
  
  let solutions: Vec<[u8; 81]> = vec![
      [
          6, 4, 5, 9, 2, 8, 3, 7, 1,
          9, 7, 3, 1, 4, 6, 2, 5, 8,
          2, 8, 1, 7, 5, 3, 9, 4, 6,
          5, 9, 8, 4, 3, 7, 6, 1, 2,
          3, 2, 7, 6, 1, 9, 5, 8, 4,
          1, 6, 4, 5, 8, 2, 7, 3, 9,
          8, 1, 9, 2, 7, 5, 4, 6, 3,
          7, 3, 2, 8, 6, 4, 1, 9, 5,
          4, 5, 6, 3, 9, 1, 8, 2, 7,
  ]];
  
  assert_eq!(solve_sudoku(sudoku), solutions);
  

---

March 16, 2025

• Bhavani Shankar Moving my family to conversations (XMPP)

  Conversations is really awesome. It is a secure, private and decentralized chat app. There is no privacy invading ads company like meta running the service. I was sold and wanted to try it out with my family. Only one small issue - conversations costs ₹550 in the play store. People don't like paying for software in our country. They would say:

  "I can eat for a week with 500 rupees. Let meta have my data and give me WhatsApp for free."

  I have lost this argument many times. Fine, we need not pay for it right now. So, I told my brother about F-Droid - an app store with only free apps. Since our parents cannot install the app by themselves, he would set up their accounts too. I live away. So, I had to guide him through each step on the phone. Little did I know that this would turn out to be much harder than I had anticipated.

  Installing F-Droid

  My brother opened Chrome in his phone and searched for F-Droid. He found the website and clicked "download apk". He told me it had disappeared. That's weird. I told him to download it again. This time, it asked "Do you want to download this file again?". Huh. Maybe it was already downloaded, so we went searching for it in files. We found it after some digging. I then got him to "allow unknown sources" and to install it. It was buried in the ginormous list of bloatware apps that came with his phone.

  Installing conversations

  F-Droid greeted us with an empty list of apps. We pressed the refresh - nothing. After waiting for 5 minutes, we hung up the phone. I called him back after a couple of hours. The repository has synced by then. We were elated to finally see a list of apps and install conversations.

  Setting up accounts

  My brother comes home every Sunday. So, we had to do this today. He created 3 accounts - one for each of their phones. But, he made our parents accounts on the wrong phones by mistake. So, he had to log out the account from each of their phones and login to the right accounts. But there was catch:

  He forgot their passwords. He wrote the passwords down on a piece of paper, but our mom locked it away for safety and went out.

  I could have killed myself here, but I restrained. We decided to update the profile names instead. I couldn't see their updated names until I deleted their contacts and added them back.

  Conclusion

  I later found Quicksy in the play store. It is the same as Conversations, but with the convenience of registering an account with a phone number - no need of user IDs and passwords. Instead of going through all this trouble, I should have asked them to install Quicksy. Sending SMS is costly. Then, why is this app free but not conversations? Why don't they have just one app that lets you register using both options?

  I now understand the UX barrier to open source technologies a bit better. Open source needs to invest in design and simplify user onboarding. Otherwise, the unethical counterparts will keep winning.

---

March 14, 2025

• Ravi Dwivedi Libreoffice Conference 2024 in Luxembourg

  Last year, I attended the annual LibreOffice Conference in Luxembourg with the help of a generous travel grant by The Document Foundation (TDF). It was a three-day event from the 10th to the 12th of October 2024, with an additional day for community meetup on the 9th.

  Luxembourg is a small (twice as big as Delhi) country in Western Europe. After going through an arduous visa process, I reached Luxembourg on the 8th of October. Upon arriving in Luxembourg, I took a bus to the city center, where my hotel — Park Inn — was located. All the public transport in Luxembourg was free of cost. It was as if I stepped in another world. There were separate tracks for cycling and a separate lane for buses, along with good pedestrian infrastructure. In addition, the streets were pretty neat and clean.

  

  

  My hotel was 20 km from the conference venue in Belval. However, the commute was convenient due to a free of cost train connection, which were comfortable, smooth, and scenic, covering the distance in half an hour. The hotel included a breakfast buffet, recharging us before the conference.

  

  Pre-conference, a day was reserved for the community meetup on the 9th of October. On that day, the community members introduced themselves and their contributions to the LibreOffice project. It acted as a brainstorming session. I got a lovely conference bag, which contained a T-Shirt, a pen and a few stickers. I also met my long time collaborators Mike, Sophie and Italo from the TDF, whom I had interacted only remotely till then. Likewise, I also met TDF’s sysadmin Guilhem, who I interacted before regarding setting up my LibreOffice mirror.

  

  The conference started on the 10th. There were 5 attendees from India, including me, while most of the attendees were from Europe. The talks were in English. One of the talks that stood out for me was about Luxchat — a chat service run by the Luxembourg government based on the Matrix protocol for the citizens of Luxembourg. I also liked Italo’s talk on why document formats must be freedom-respecting. On the first night, the conference took us to a nice dinner in a restaurant. It offered one more way to socialize with other attendees and explore food at the same time.

  

  

  On the 11th of October, I went for a walk in the morning with Biswadeep for some sightseeing around our hotel area. As a consequence, I missed the group photo of the conference, which I wanted to be in. Anyway, we enjoyed roaming around the picturesque Luxembourg city. We also sampled a tram ride to return to our hotel.

  

  

  The conference ended on the 12th with a couple of talks. This conference gave me an opportunity to meet the global LibreOffice community, connect and share ideas. It also gave me a peek into the country of Luxembourg and its people, where I had good experience. English was widely known, and I had no issues getting by.

  Thanks to all the organizers and sponsors of the conference!

---

• Thejeshgn GN Weekly Notes 11/2025

  The first half of the week was busy, with most of the time, including some weekend hours, spent closing work TODOs. But now that we're in Langkawi, it's all good :)

  

  • I got to speak to another open data community in India, the India Open LandCover Initiative. It was a quick talk about my view on building communities as a DataMeet organizer.
  • One reason I hate multiple communication channels between the same folks is confusion. I recently received something on WhatsApp; a few days later, I searched my email inbox for 20 minutes to no avail. Then I found it on WhatsApp. Ideally, I think all business should be done by Email, which is searchable!
  • I finally watched Vaazhai by Mari Selvaraj. It's a slow and simple movie where the story is told through the eyes of the main character, Sivanaindhan, a school-going boy who works at a banana plantation during the weekends. Anything more will be a spoiler. I liked it, go watch it; you will like it too.
  • We reached Langkawi on Wednesday morning. First impressions - a small, clean island with friendly people. Lots of lovely beaches, the best place to do nothing. We will be here for a week; I will write more later.
  • I miss Pathu; she is with Stay Benaglore and Echo, and he is with his grandparents.
  • I have been contributing to BeaconDB, a public-domain wireless beacon location database. I used to be a serious contributor to Mozilla Location Service, which, of course, was shut down in 2024. Mozilla used to have a leader-board that made the contribution fun. BeaconDB does not have any such feature to keep contributors' details private. But to keep my competitive mind going, I have promised myself that I would contribute one Lakh unique beacons (wifi+cell+ble). I am far away from it with a unique count of wifi=5257, cell=1141, and ble=34 beacons. Traveling helps.
  • Nagarathna Memorial Grant – 2025 - Application closes tomorrow, March 15 anywhere on earth (AOE) time.

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March 13, 2025

• Bhavani Shankar Easy math puzzle with an unbelievable answer

  The answer to this puzzle is so surprising that it has lingered in my mind for decades. Try to solve it before looking at the answer. How would you explain the solution intuitively?

  In a class of 500 students, 99% are right-handed. How many right-handers should leave the class to make it 98%?

  Solution

  The class has 99% right-handers. So, the number of right-handed students is:

  The remaining 5 are left-handed.

  Say right-handed students left the class. Then the number of right-handed students left is:

  The total number of students left is:

  We know that the ratio of these two is 98%.

  When we substitute the values of and , we get:

  Cross multiplying,

  Let the answer sink in a bit. You have to remove half of the class to move the percentage of right-handers by just one percent - i.e. from 99% to 98%. How would you make sense of it?

  Intuitive explanation

  What if I asked you this question instead?

  Let's say you have a glass of sugar water. You leave the glass outside and let some water evaporate until its sweetness doubles. How much sugar water will be remaining in the glass?

  It is quite intuitive that exactly half of sugar solution will be left. This is the exact same puzzle as above. Just like the sugar, the concentration of left-handed students doubled from 1% to 2%.

  This problem came to be known as the famous Potato paradox. The "paradox" comes from the way this problem is poised - by focusing on water instead of the sugar. In math and in life, language and mulling over the wrong things can obscure the truth. When we rephrase, things becomes simple and transparent.

---

March 10, 2025

• Bhavani Shankar Designing effective types in Rust

  We use type systems to minimize the subset of valid inputs to an API. That's it. Nothing more. Thoughts are non-linear and messy. So, we make mistakes while turning our thoughts into code which needs to be precise. Using this guiding principle, we can often arrive at the best types for business logic.

  Diving into an example

  Let's say we are writing a university management software. We need to store a record of everyone who stays there.

  struct Professor {
    id: u64,
    name: String,
    email: String,
    department: Department,
  }
  
  struct Student {
    id: u64,
    name: String,
    email: String,
    courses: Vec<Course>,
  }
  
  struct Worker {
    id: u64,  
    name: String,
    job: Job,
  }
  

  How do we define a data type for a person who can be any of these 3 types? Three ways come to mind.

  Outer struct

  enum PersonType {
    Professor,
    Student,
    Worker,
  }
  
  struct Person {
    person_type: PersonType,
    id: i64,
    name: String,
    email: Option<String>,
    courses: Option<Vec<Course>>,
    job: Option<Job>,
  }
  

  In this approach, we turn all fields that are not common to every type into options and define an enum for person type. Person becomes a struct - a loose type that can contain invalid states. For example, we can create a Person of type Worker with the courses field.

  // Oh no! an invalid person.
  Person {
    id: 0,
    person_type: PersonType::Worker,
    name: String,
    courses: Vec::new(),
  }
  

  Outer enum

  To avoid this issue, we can write the person type using an Enum instead. Using this strict type, we have eliminated the invalid states. Yay!

  enum Person {
    Professor(Professor),
    Student(Student),
    Worker(Worker),
  }
  

  Which is better?

  Though our outer enum looks perfect, a hidden cost emerges from it - a verbose API. The outer struct has no nesting and can be directly stored in an SQL database. Using the enum requires pattern matching.

  // Constructing a person
  let person = Person::Professor(Professor {
    id: 0,
    email: "joe@example.gov",
    department: Department::Sciences(ScienceSubject {
      id: 0,
      name: "Computer Science",
      labs: Vec<Lab>,
      ...
    })
  });
  
  // accessing a field in person enum like email
  let email = match person {
      Person::Student(Student { email, .. }) | Person::Professor(Professor { email, .. }) => {
          Some(email)
      }
      Person::Worker(worker) => None,
  };
  

  When we compare the above to:

  // Constructing a person
  let person = Person {
    id: 0,
    person_type: PersonType::Professor,
    email: Some("joe@example.gov"),
    department: Department {
      id: 0,
      name: "Computer Science",
      labs: Vec<Lab>,
      ...
    })
  });
  
  // accessing a field in person enum like email
  let email = person.email;
  

  See how terse using the struct can be? The mixed approach has all the benefits of outer enum and is less verbose.

  Mixed approach

  There is another strict type we can construct for this problem - extract the common fields into a struct and rewrite the data types as follows:

  struct StudentPart {
    email: String,
    courses: Vec<Course>,
  }
  
  struct ProfessorPart {
    email: String,
    department: Department,
  }
  
  struct WorkerPart {
    job: Job
  }
  
  enum PersonType {
    Professor(ProfessorPart),
    Student(StudentPart),
    Worker(WorkerPart),
  }
  
  struct Person {
    id: i64,
    name: String,
    person_type: PersonType
  }
  

  Updating fields in mixed approach

  The mixed approach has gotten a bit non-trivial. So, it is useful to think about the correct approach of implementing methods on it. I use traits for shared behaviors like updating a common field like email.

  // Use type implementation for unique fields
  impl Person {
    fn update_name(&mut self, name: &str) {
      self.name = name.to_owned();
    }
  }
  
  // email is shared by both Professor and Student so we can
  // use a trait for common behavior across shared fields
  trait EmailUpdate {
    fn update_email(&mut self, email: &str);
  }
  
  impl EmailUpdate for StudentPart {
    fn update_email(&mut self, email: &str) {
      self.email = email.to_owned();
    }
  }
  
  impl EmailUpdate for ProfessorPart {
    fn update_email(&mut self, email: &str) {
      self.email = email.to_owned();
    }
  }
  
  // Add implementations for other fields in StudentPart, ProfessorPart, WorkerPart
  // in a similar way.
  // ...
  

  If there were more attributes like email which are shared between StudentPart and ProfessorPart, I would consider segregating them into a struct and an inner enum too like we did with Person.

  Conclusion

  I prefer the mixed approach for Person type when it constructed and updated in many places without control. E.g. public APIs of a crate, forms, and common parts of a large crate etc. For small localized use like fetching an external API and caching the result in a database, I lean towards the flat struct. Shoutout, and thanks to Dusty Pomerleau for being kind enough to suggest some corrections.

  This principle of balancing strict types with API convenience requires careful thought for each use case.

---

March 07, 2025

• Thejeshgn GN Weekly Notes 10/2025

  Appa was down with a fever and an upset stomach for a couple of days. He recovered pretty fast. Now that Uma can make sentences of two or three words from different languages, their conversation is fun to hear. She probably has a combined vocabulary of 100 words in Malayalam, Kannada, and English. She combines words from all three without hesitation and with ease.

  

  • At work, it was a busy week. We are traveling to a different timezone next week, so I had to clear as many tasks as possible—so many more reviews, merges, deployments, meetings to remove blockers or dependencies, etc. While I'm usually available when traveling, my teams are reliable, and they rarely contact me on vacation, which makes me feel more responsible.
  • I talked to a bunch of folks about open data and its availability in India. It's good to be back talking about Open Data.
  • Subscribed to Anil Radhakrishna, thanks to Anand's post. I subscribed to another bunch, thanks to Sai's post. I am yet to update the blogring with these discoveries. I will this weekend.
  • I don't understand why we idealize kings and queens in the 21st century. They were self-appointed rulers who did whatever it took to stay in power—killing siblings, subjects, soldiers, and rivals. It was just business as usual. We are born and living in democracies and republics. We should strengthen these systems instead of fighting over monarchs and dividing society. Studying history is essential, but its lessons should be used to build the present society, not destroy it.
  • I've been reading Mike Masnick and TechDirt for over two decades. I love their coverage of tech, copyright, licenses, and the public domain. In a recent post, he noted that every tech discussion now is about democracy. I agree, but for us in India, this has been the case for over a decade. You could see the shift as soon as Aadhaar was forced upon us.
  • From a TED Talk by Simone: Certainly, we are all more than just workers. We're parents and friends and citizens and artists and travelers and neighbors. Much like an investor benefits from diversifying the sources of stocks in their portfolio, we, too, benefit from diversifying the sources of meaning and identity in our lives. But how do you actually go about doing so? I agree with Simone; we are a sum of many roles we play in this life.

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• Bhavani Shankar Being a chicken in a farm

  Consider a thought experiment that says a lot about the human condition:

  Imagine waking up as a chicken in a farm. You don't have any memories as a human, but you are intelligent. Observing the world around you, you start wondering about the meaning of your existence. You see a fence beyond which you cannot leave. There is a really powerful being (a human) taking care of you. Let's call him Bob. Who is Bob and what does he want?

  1. Bob is a kind being sharing his abundance of resources with you.
  2. Maybe he is evil. Bob is probably just using you for a cause.

  You have no idea which of these two hypotheses is likely to be true. What should you believe and talk to your friends about?

  Our circumstances in this universe is the same too. We wake up one day, look around and ponder our existence. A planet full of life and a vast empty space tingles our imagination. We see nature and powerful forces like gravity.

  Pragmatic beliefs

  Let's go back to Chi the chicken (I just gave her a name). Chi has 3 belief choices:

  1. That Bob is a compassionate being
  2. That Bob has malevolent intentions
  3. Stay skeptical of either

  Let's examine (2) which is the objective truth. Chi does not know. But if she believed it, she would feel fear, hatred, and helplessness every time Bob comes to feed her. Throughout her life, she would spread misery to her friends and family. So I would argue it is a wrong worldview.

  (3) is definitely an improvement over (2). Chi would live her life in doubt and its close friends - apathy and inaction.

  We know (1) is false. But if chi adopts this view, she will feel gratitude each time the Bob brings her food. Throughout her life, she would spread news about how kind Bob was today. Her friends dance in joy. Chi asks herself what if she was wrong. She knows she can't escape Bob. When the day comes, she will have to fulfill whatever purpose Bob had for her. There is no use sweating it now.

  Conclusion

  This is the right view. Chi didn't know her fate until her very last moments. She died living a lie, but she enjoyed her life thoroughly and minimized suffering for everybody around her.

  The future that's awaiting us is probably not so terrible. Or maybe it is worse. Who knows? Let's be optimistic, compassionate and trusting. It's okay to be wrong sometimes.

  This doesn't mean deny the truth and be blindly optimistic. Pragmatic beliefs are needed in the absence of evidence. We have to set our ego aside and keep an open mind. The truth can present itself anytime.

---

February 28, 2025

• Thejeshgn GN Weekly Notes 09/2025

  My neck is doing okay. Resting, i.e., not looking at the phone but sleeping, has greatly helped. I'm still wearing the cervical collar, as the doctor advised. I've also slowed down on the work front this week because of it. Hopefully, I will be able to catch up next week.

  

  • We went out for lunch with friends at Kuuraku, Bangalore. I liked the starters, though I thought they were expensive.
  • I downloaded all my Kindle books. I had stopped buying books on Kindle a long time ago. Now, I am kind of completely out of that ecosystem. I am still looking for a decent portable e-ink device. Ideally, a 6-inch one that runs Android so that I can configure it however I want. Something Boox Palma, or maybe fix my old Kindle keyboard and jailbreak it.
  • I got tagged by Sathya and, as a response, wrote - A challenge of blog questions.
  • It's good to see people discussing air quality and AQI because of Bryan Johnson. I don't know why people have taken so long to understand air pollution is killing us. There have been some folks who have been raising concerns for more than a decade now. It's going to hurt the middle and lower middle class like any environmental disaster.
  • A cartoon can get a century-old news magazine - Vikatan's website blocked by the government without notice. We have a long way to go as a democracy.
  • Appa is here; he has a bit of a fever due to travel.
  • I updated the bengaluru_airport_estimated_wait_time scraper to get the correct data. They had updated their backend to include origin validation. I had not looked at the status of the scraper for a long time. It failed sometime in 2023, so we lost the complete 2024 data. Anyway, it's up, and data is being collected now. The data format has also changed; now that we have T2 and T1 is all domestic. The readme and the load.sh needs an update to handle the new format data. I will do it once I have collected some data. Reminder: Set up status alerts for all my public scraping jobs.
  • I have been using qwen2.5:0.5b, the smallest qwen2.5 model, locally using Ollama and Open WebUI. It runs pretty well, even on my CPU-only machine. Currently, I am using it to summarize the documents, ask questions about them, etc. I am very impressed. I want to try qwen2.5-coder:0.5b next to see what it can do. I am fascinated by small (i.e., less than 1 GB) large language models 😄 I want to push them to their limits and see everything they can do.

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February 10, 2025

• FSCI Planet FSCI

  In the age of “AI in everything”, one could wonder if writing and maintaining an individual blog is still relevant. “AI in everything” LLMs has gobbled up millions of lines of texts, audio, code and what not to generate its responses. Can an individual do better through their blog? Uncertain. But again, individual blogs are for a person’s own expression; of their thoughts, understandings and world view. It’s the human (touch).

  Now coming to the topic, blog planet and Planet FSCI. Blog planet(s) serve as blog aggregators where writings from community members land up. Whenever someone posts on their individual blog, planet software automatically fetches it make it part of Planet feed. It’s a look at what’s happening in the community and what new adventures are people up to. It feels like blog planets are historic “social media timelines” where you go to check in on your friends and their whereabouts. Blog planets seem to exist as long a Free Software communities exists. Quite a lot of big projects seems to have them like Debian, DGPLUG, GNOME and others.

  Side note - I’m curious to know if blog planets existed outside free software communities. Let me know if you know any instances of these.

  On a similar theme, FSCI has a planet too for community members. Planet FSCI can be read via multiple avenues. I personally prefer going through the website itself, i.e. https://planet.fsci.in/. I do have Atom Feed subscribed through my feed reader (Thunderbird on laptop and Feeder on Mobile.). New posts also get automatically posted in #FSCI (Matrix/XMPP/IRC) main channel.

  Community members and Free Software enthusiasts are encouraged to join. We never really fully discussed and documented who can join Planet FSCI, but most will agree if you’re into Free Software and technology in general, you’re fit to join. These are not hard restrictions though for your blog posts too. Just be nice. You can send a merge request here with RSS or Atom feed of your blog. Sending a mail with feed link to admin AT fsci.in works too. I’ll appreciate, if the feed has text in full and not just summary. Planets are not link aggregators and I (like many others) love to read your blog in my feed reader only (rather than switching to my browser just to read your blog), thanks!

  If you don’t have a blog, may this serve as the motivation to start one. DGPLUG’s article on blogging comes as a much recommended read. I too, wrote about my motivation to write, back in 2020. The blog takes the personality of its author. Technical writings, creative outflows, little tips and tricks or simple musings in life, personal blogs carry everything. My blog is one of my outflows. I have had interesting discussions on topics I deeply care about simply because people have read my blogs and met me to discuss different perspective and share information with me. That’s a bliss of writing. Another way, I look as this blog writing as writing my own history. It’s been almost 5 years, since I started writing online (and still sometimes wonder that’s long time to continue with a hobby). I still keep going back to some of my writings just to understand my mindset then, and in general they’re fun to read.

  Blogs are windows to someone’s thoughts and life, and Planet is the town square where you can peer ;)

  In conclusion, this writing on FSCI Planet (or Planet FSCI) is going to come up on Planet FSCI as well. See you there. ;)

---

January 21, 2025

• Ravi Dwivedi The Arduous Luxembourg Visa Process

  In 2024, I was sponsored by The Document Foundation (TDF) to attend the LibreOffice annual conference in Luxembourg from the 10th to the 12th of October. Being an Indian passport holder, I needed a visa to visit Luxembourg. However, due to my Kenya trip coming up in September, I ran into a dilemma: whether to apply before or after the Kenya trip.

  To obtain a visa, I needed to submit my application with VFS Global (and not with the Luxembourg embassy directly). Therefore, I checked the VFS website for information on processing time, which says:

  As a rule, the processing time of an admissible Schengen visa application should not exceed 15 calendar days (from the date the application is received at the Embassy).

  It also mentions:

  If the application is received less than 15 calendar days before the intended travel date, the Embassy can deem your application inadmissible. If so, your visa application will not be processed by the Embassy and the application will be sent back to VFS along with the passport.

  If I applied for the Luxembourg visa before my trip, I would run the risk of not getting my passport back in time, and therefore missing my Kenya flight. On the other hand, if I waited until after returning from Kenya, I would run afoul of the aforementioned 15 working days needed by the embassy to process my application.

  I had previously applied for a Schengen visa for Austria, which was completed in 7 working days. My friends who had been to France told me they got their visa decision within a week. So, I compared Luxembourg’s application numbers with those of other Schengen countries. In 2023, Luxembourg received 3,090 applications from India, while Austria received 39,558, Italy received 52,332 and France received 176,237. Since Luxembourg receives a far fewer number of applications, I expected the process to be quick.

  Therefore, I submitted my visa application with VFS Global in Delhi on the 5th of August, giving the embassy a month with 18 working days before my Kenya trip. However, I didn’t mention my Kenya trip in the Luxembourg visa application.

  For reference, here is a list of documents I submitted:

  • Passport
  • Photocopy of passport data pages
  • Visa application form
  • One photograph
  • Visa appointment confirmation
  • Cover letter
  • Return flight reservations
  • Hotel bookings
  • Invitation letter from the conference organizer, TDF
  • Confirmation from The Luxembourg Convention Bureau G.I.E - the venue
  • Last three months bank account statement with bank seal
  • Travel insurance
  • Income Tax Return Statement
  • Monthly payslips for the last three months

  I submitted ‘flight reservations’ instead of ‘flight tickets’. It is because, in case of visa rejection, I would have lost a significant amount of money if I booked confirmed flight tickets. The embassy also recommends the same. After the submission of documents, my fingerprints were taken.

  The expenses for the visa application were as follows:

  Service Description	Amount (INR)
  Visa Fee	8,114
  VFS Global Fee	1,763
  Courier	800
  Total	10,677

  Going by the emails sent by VFS, my application reached the Luxembourg embassy the next day. Fast-forward to the 27th of August — 14th day of my visa application. I had already booked my flight ticket to Nairobi for the 4th of September, but my passport was still with the Luxembourg embassy, and I hadn’t heard back. In addition, I also obtained Kenya’s eTA and got vaccinated for Yellow Fever, a requirement to travel to Kenya.

  In order to check on my application status, I gave the embassy a phone call, but missed their calling window, which was easy to miss since it was only 1 hour - 12:00 to 1:00 PM. So, I dropped them an email explaining my situation. At this point, I was already wondering whether to cancel the Kenya trip or the Luxembourg one, if I had to choose.

  After not getting a response to my email, I called them again the next day. The embassy told me they would look into it and asked me to send my flight tickets over email. One week to go before my flight now.

  I followed up with the embassy on the 30th by a phone call, and the person who picked up the call told me that my request had already been forwarded to the concerned department and is under process. They asked me to follow up on Monday, 2nd September.

  During the visa process, I was in touch with three other Indian attendees.¹ In the meantime, I got to know that all of them had applied for a Luxembourg visa by the end of the month of August.

  Back to our story, over the next two days, the embassy closed for the weekend. I began weighing my options. On one hand, I could cancel the Kenya trip and hope that Luxembourg goes through. Even then, Luxembourg wasn’t guaranteed as the visa could get rejected, so I might have ended up missing both the trips. On the other hand, I could cancel the Luxembourg visa application and at least be sure of going to Kenya. However, I thought it would make Luxembourg very unlikely because it didn’t leave 15 working days for the embassy to process my visa after returning from Kenya. I also badly wanted to attend the LibreOffice conference because I couldn’t make it two years ago. Therefore, I chose not to cancel my Luxembourg visa application. I checked with my travel agent and learned that I could cancel my Nairobi flight before September 4th for a cancelation fee of approximately 7,000 INR.

  On the 2nd of September, I was a bit frustrated because I hadn’t heard anything from the embassy regarding my request. Therefore, I called the embassy again. They assured me that they would arrange a call for me from the concerned department that day, which I did receive later that evening. During the call, they offered to return my passport via VFS the next day and asked me to resubmit it after returning from Kenya. I immediately accepted the offer and was overjoyed, as it would enable me to take my flight to Nairobi without canceling my Luxembourg visa application. However, I didn’t have the offer in writing, so it wasn’t clear to me how I would collect my passport from VFS. The next day, I would receive it when I would be on my way to VFS in the form of an email from the embassy which read:

  Dear Mr. Dwivedi,

  We acknowledge the receipt of your email.

  As you requested, we are returning your passport exceptionally through VFS, you can collect it directly from VFS Delhi Center between 14:00-17:00 hrs, 03 Sep 2024. Kindly bring the printout of this email along with your VFS deposit receipt and Original ID proof.

  Once you are back from your trip, you can redeposit the passport with VFS Luxembourg for our processing.

  With best regards,
  Consular Section

  GRAND DUCHY OF LUXEMBOURG
  Embassy in New Delhi

  I took a printout of the email and submitted it to VFS to get my passport. This seemed like a miracle - just when I lost all hope of making it to my Kenya flight and was mentally preparing myself to miss it, I got my passport back “exceptionally” and now I had to mentally prepare again for Kenya. I had never heard of an embassy returning passport before completing the visa process before. The next day, I took my flight to Nairobi as planned. In case you are interested, I have written two blog posts on my Kenya trip - one on the OpenStreetMap conference in Nairobi and the other on my travel experience in Kenya.

  After returning from Kenya, I resubmitted my passport on the 17th of September. Fast-forward to the 25th of September; I didn’t hear anything from the embassy about my application process. So, I checked with TDF to see whether the embassy reached out to them. They told me they confirmed my participation and my hotel booking to the visa authorities on the 19th of September (6 days ago). I was wondering what was taking so long after the verification.

  On the 1st of October, I received a phone call from the Luxembourg embassy, which turned out to be a surprise interview. They asked me about my work, my income, how I came to know about the conference, whether I had been to Europe before, etc. The call lasted around 10 minutes. At this point, my travel date - 8th of October - was just two working days away as the 2nd of October was off due to Gandhi Jayanti and 5th and 6th October were weekends, leaving only the 3rd and the 4th. I am not sure why the embassy saved this for the last moment, even though I submitted my application 2 months ago. I also got to know that one of the other Indian attendees missed the call due to being in their college lab, where he was not allowed to take phone calls. Therefore, I recommend that the embassy agree on a time slot for the interview call beforehand.

  Visa decisions for all the above-mentioned Indian attendees were sent by the embassy on the 4th of October, and I received mine on the 5th. For my travel date of 8th October, this was literally the last moment the embassy could send my visa. The parcel contained my passport and a letter. The visa was attached to a page in the passport. I was happy that my visa had been approved. However, the timing made my task challenging. The enclosed letter stated:

  Subject: Your Visa Application for Luxembourg

  Dear Applicant,

  We would like to inform you that a Schengen visa has been granted for the 8-day duration from 08/10/2024 to 30/10/2024 for conference purposes in Luxembourg.

  You are requested to report back to the Embassy of Luxembourg in New Delhi through an email (email address redacted) after your return with the following documents:

  • Immigration Stamps (Entry and Exit of Schengen Area)
  • Restaurant Bills
  • Shopping/Hotel/Accommodation bills

  Failure to report to the Embassy after your return will be taken into consideration for any further visa applications.

  I understand the embassy wanting to ensure my entry and exit from the Schengen area during the visa validity period, but found the demand for sending shopping bills excessive. Further, not everyone was as lucky as I was as it took a couple of days for one of the Indian attendees to receive their visa, delaying their plan. Another attendee had to send their father to the VFS center to collect their visa in time, rather than wait for the courier to arrive at their home.

  Foreign travel is complicated, especially for the citizens of countries whose passports and currencies are weak. Embassies issuing visas a day before the travel date doesn’t help. For starters, a last-minute visa does not give enough time for obtaining a forex card as banks ask for the visa. Further, getting foreign currency (Euros in our case) in cash with a good exchange rate becomes difficult. As an example, for the Kenya trip, I had to get US Dollars at the airport due to the plan being finalized at the last moment, worsening the exchange rate. Back to the current case, the flight prices went up significantly compared to September, almost doubling. The choice of airlines also got narrowed, as most of the flights got booked by the time I received my visa. With all that said, I think it was still better than an arbitrary rejection.

  Credits: Contrapunctus, Badri, Fletcher, Benson, and Anirudh for helping with the draft of this post.

  ---

  1. Thanks to Sophie, our point of contact for the conference, for putting me in touch with them. ↩︎

---

January 12, 2025

• Sahil Dhiman Prosody Certificate Management With Nginx and Certbot

  I have a self-hosted XMPP chat server through Prosody. Earlier, I struggled with certificate renewal and generation for Prosody because I have Nginx (and a bunch of other services) running on the same server which binds to Port 80. Due to this, Certbot wasn’t able to auto-renew (through HTTP validation) for domains managed by Prosody.

  Now, I have cobbled together a solution to keep both Nginx and Prosody happy. This is how I did it:

  • Expose /.well-known/acme-challenge through Nginx for Prosody domain. Nginx config looked like this:

  server {
        listen 80;
        listen [::]:80;
        server_name PROSODY.DOMAIN;
        root <ANY_NGINX_WRITABLE_LOCATION>;
  
        location ~ /.well-known/acme-challenge {
           allow all;
        }
  }
  

  • Run certbot to get certificates for <PROSODY.DOMAIN>.
  • To use those in Prosody, add a cron entry for root user:

  0 0 * * * prosodyctl --root cert import /etc/letsencrypt/live/PROSODY.DOMAIN
  

  Explanation from Prosody docs:

  Certificates and their keys are copied to /etc/prosody/certs (can be changed with the certificates option) and then it signals Prosody to reload itself. –root lets prosodyctl write to paths that may not be writable by the prosody user, as is common with /etc/prosody.

  • Certbot now manages auto-renewal as well, and we’re all set.

---

January 01, 2025

• Bhavani Shankar Meditation changes everything

  "The mind is the forerunner of all things." -- The Dhammapada

  This post is my ode to the ancient practice of meditation and mindfulness. Thank you for showing how deep the mind's conditioning and perceptual habits go. The mind does create your world. Much gratitude for changing everything. If you don't believe me, here's what science has to say:

  Physical effects

  • Dramatic reduction in levels of unease and stress
  • Reduced blood pressure, heart rate and breath rate
  • Increases immune function
  • Reduces inflammation at cellular level
  • Improves sleep and recovery

  Effects on the Brain

  • Slows down age related cognitive decline
  • Increases neural plasticity
  • Increases gray matter
  • Increases cortical thickness in areas related to attention
  • Increases volume in areas related to emotional regulation, positive emotions and self-control

  Emotional effects

  • Increases your ability to adapt to new situations
  • Increases positive emotions
  • Decreases worry, depression and anxiety
  • Reduces rumination of past painful experiences
  • Improves relationships and social intelligence
  • Makes you more compassionate
  • Reduces Loneliness
  • Increases introspection and self-acceptance
  • Better emotional regulation

  Mental Illness and Addictions

  • Effective in treating psychosis
  • Promising for treating PTSD and trauma
  • Reduces substance abuse, cravings and relapse

  Productivity and Learning

  • Increased focus and attention
  • Increases goal oriented behavior
  • Better memory
  • Improves ability to multitask
  • Improves individual intelligence and IQ scores.

  Effects on Perception

  • Dramatically alters consciousness, sense of self and passage of time.
  • Meditators perceive the world more objectively and in higher detail
  • Meditation reduces the effect of certain optical illusions
  • Decreases both acute pain and is great for managing chronic pain

---

December 23, 2024

• Sahil Dhiman Debian Mirrors Hierarchy

  After finding AlmaLinux mirror sync capacity at Tier 0 (or Tier 1, however you look at it) is around 140 Gbps, I wanted to find source and hierarchy in Debian mirroring systems.

  There are two main types of mirrors in Debian - Debian package mirrors (for package installs and updates) and Debian CD mirrors (for ISO and others medias). Let’s talk about package mirrors (and it’s hierarchy) first.

  Package mirror hierarchy

  Trace file was a good starting point for checking upstream for a package mirror in Debian. It resides at <URL>/debian/project/trace/_traces and shows flow of data. Sample trace file from jing.rocks’s mirror. It showed, canonical source for packages is ftp-master.debian.org. Checking via https://db.debian.org/machines.cgi, showed it’s fasolo.d.o hosted at Brown University, US. This serves as “Master Archive Server”, making it a Tier 0 mirror. It’s entry mentions that it has 1 Gbps shared LAN connectivity (dated information?) but it only has to push to 3 other machines/sites.

  Side note - .d.o is .debian.org

  As shown on https://mirror-master.debian.org/status/mirror-hierarchy.html, the three sites are:

  • syncproxy2.eu.debian.org ie smit.d.o hosted by University of Twente, Netherlands with 2x10 Gbps connectivity.
  • syncproxy4.eu.debian.org ie schmelzer.d.o hosted by Conova in Austria with 2x10 Gbps connectivity.
  • syncproxy2.wna.debian.org - https://db.debian.org/machines.cgi entry mentions it being hosted at UBC here, but IP seems to be pointing to OSUOSL IP range as of now. IIRC few months ago, syncproxy2.wna.d.o was made to point to other host due to some issue (?). mirror-osuosl.d.o seems to be serving as syncproxy2.wna.d.o now. Bandwidth isn’t explicitly mentioned but from my experience seeing bandwidths which other free software projects hosted at OSUOSL have, it would be atleast 10 Gbps and maybe more for Debian.

  
                       syncproxy2.eu.d.o (NL) ---> to the world
                      /
  ftp-master.d.o (US) -- syncproxy4.eu.d.o (AT)  --> to the world 
                      \
                       syncproxy2.wna.d.o (US) --> to the world
  

  A visualation of flow of package from ftp-master.d.o

  These form the Debian Tier 1 mirror network, as all the mirrors sync from them. So Debian has atleast 50 Gbps+ capacity at Tier 1. A normal Debian user might never directly interact with any of these 3 machines, but every Debian package they run/download/install flows through these machines. Though, I’m unsure what wna stands for in syncproxy2.wna.d.o. NA probably is North America and W is west (coast)? If you know, do let me know.

  After Tier 1, there are a few more syncproxies (detailed below). There are atleast 45 mirrors at Tier 2, updates for which are directly pushed from the three Tier 1 sync proxies. Most country mirrors i.e. ftp..debian.org are at Tier 2 too (barring a few like ftp.au.d.o, ftp.nz.do etc).

  Coming back to Sync proxies at Tier 2:

  • syncproxy3.wna.debian.org - gretchaninov.d.o which is marked as syncproxy2 on db.d.o (information dated). It’s hosted in University of British Columbia, Canada, where a lot of Debian infrastructure including Salsa is hosted.
  • syncproxy.eu.debian.org - Croatian Academic and Research Network managed machine. CNAME directs to debian.carnet.hr.
  • syncproxy.au.debian.org - mirror-anu.d.o hosted by Australian National University with 100Mbps connectivity. Closest sync proxy for all Australian mirrors.
  • syncproxy4.wna.debian.org - syncproxy-aws-wna-01.d.o hosted in AWS, in US (according to GeoIP). IPv6 only (CNAME to syncproxy-aws-wna-01.debian.org. which only has an AAAA record, no A record). A m6g.2xlarge instance which has speeds upto 10 Gbps.

  Coming back to https://mirror-master.debian.org/status/mirror-hierarchy.html, one can see chain extend till Tier 6 like in case of this mirror in AU which should add some latency for the updates from being pushed at ftp-master.d.o to them. Ideally, which shouldn’t be a problem as https://www.debian.org/mirror/ftpmirror#when mentions “The main archive gets updated four times a day”.

  In my case, I get my updates from NITC mirror, so my updates flows from US > US > TW > IN > me in IN.

  CDNs have to internally manage cache purging too unlike normal mirrors which directly serve static file. Both deb.debian.org (sponsored by Fastly) and cdn-aws.deb.debian.org (sponsored by Amazon Cloudfront) sync from following CDN backends:

  • mirror.accumu.d.o hosted by Academic Computer Club in Umeå, Sweden.
  • mirror-skroutz.d.o hosted by Skroutz Internet Services in Greece.
  • schmelzer.d.o hosted by Conovo in Austria.

  See deb.d.o trace file and cdn-aws.deb.d.o trace file.

  (Thanks to Philipp Kern for the heads up here.)

  CD image mirrors Hierarchy

  Till now, I have only talked about Debian package mirrors. When you see /debian directory on various mirrors, they’re usually for package install and updates. If you want to grab the latest (and greatest) Debian ISO, you go to Debian CD (as they’re still called) mirror site.

  casulana.d.o is mentioned as CD builder site hosted by Bytemark while pettersson-ng.d.o is mentioned as CD publishing server hosted at Academic Computer Club in Umeå, Sweden. Primary download site for Debian CD when you click download on debian.org homepage is https://cdimage.debian.org/debian-cd/ is hosted here as well. This essentially becomes Tier 0 mirror for Debian CD. All Debian CD mirrors are downstream to it.

  pettersson-ng.d.o / cdimage.d.o (SE) ---> to the world
  

  A visualation of flow of Debian CD from cdimage.d.o

  Academic Computer Club’s mirror setup uses a combination of multiple machines (called frontends and offloading servers) to load balance requests. Their document setup is a highly recommended read. Also, in that document, they mention , “All machines are reachable via both IPv4 and IPv6 and connected with 10 or 25 gigabit Ethernet, external bandwidth available is 200 gigabit/s.”

  For completeness sake, following mirror (or mirror systems) exists too for Debian:

  • Debian Ports mirrors.
  • Debian Archive mirrors to get old Debian versions.
  • Debian Security has bunch official mirrors (as mentioned here) behind security.d.o. It resolves to Fastly IP ranges so could be Fastly or Debian operated mirrors. Taking a look at https://db.debian.org/machines.cgi tells seger.d.o in DE is security-master which I’m assuming is source for all following mentioned security mirrors:
    • lobos.d.o in DE
    • mirror-csail.d.o in US
    • mirror-anu.d.o in AU
    • santoro.d.o in BR
    • schumann.d.o in DE
    • setoguchi.d.o in JP
    • villa.d.o in DE
    • wieck.d.o in DE

  Debian heavily rely on various organizations to donate resources (hosting and hardware) to distribute and update Debian. Compiling above information made me thankful to all these organizations. Many thanks to DSA and mirror team as well for managing these stuffs.

  I relied heavily on https://db.debian.org/machines.cgi which seems to be manually updated, so things might have changed along the way. If anything looks amiss, feel free to ping.

---

December 21, 2024

• Karthik Running Sway in openSUSE

  openSUSE tumbleweed has a good collection of sway window manager & it’s surrounding tools. There are a couple of ways to install sway & related packages

  Traditional way

  If you wish to handpick your sway setup, you can download individual packages via zypper.

  1	sudo zypper in sway waybar

  Via Patterns

  A pattern is nothing but a collection of related packages which could be installed via single keyword. Sway also has such a pattern, which can be installed via the command below. This list of packages this patterns installs are defined here.

  1	sudo zypper in patterns-sway-sway

  openSUSEway

  This is an opinionated sway desktop environment which ships with a bunch of pre configured packages & settings. More details & install instructions can be found in the openSUSEway wiki

---

November 29, 2024

• Raju Devidas Finding all sub domains of a main domain

  Problem: Need to know all the sub domains of a main domain, e.g. example.com has a sub domain dev.example.com , I also want to know other sub domains.

  Solution:

  Install the package called sublist3r, written by Ahmed Aboul-Ela

  $ sudo apt install sublist3r

  run the command

  $ sublist3r -d example.com -o subdomains-example.com.txt
  
                   ____        _     _ _     _   _____
                  / ___| _   _| |__ | (_)___| |_|___ / _ __
                  \___ \| | | | '_ \| | / __| __| |_ \| '__|
                   ___) | |_| | |_) | | \__ \ |_ ___) | |
                  |____/ \__,_|_.__/|_|_|___/\__|____/|_|
  
                  # Coded By Ahmed Aboul-Ela - @aboul3la
  
  [-] Enumerating subdomains now for example.com
  [-] Searching now in Baidu..
  [-] Searching now in Yahoo..
  [-] Searching now in Google..
  [-] Searching now in Bing..
  [-] Searching now in Ask..
  [-] Searching now in Netcraft..
  [-] Searching now in DNSdumpster..
  [-] Searching now in Virustotal..
  [-] Searching now in ThreatCrowd..
  [-] Searching now in SSL Certificates..
  [-] Searching now in PassiveDNS..
  Process DNSdumpster-8:
  Traceback (most recent call last):
    File "/usr/lib/python3.12/multiprocessing/process.py", line 314, in _bootstrap
      self.run()
    File "/usr/lib/python3/dist-packages/sublist3r.py", line 269, in run
      domain_list = self.enumerate()
                    ^^^^^^^^^^^^^^^^
    File "/usr/lib/python3/dist-packages/sublist3r.py", line 649, in enumerate
      token = self.get_csrftoken(resp)
              ^^^^^^^^^^^^^^^^^^^^^^^^
    File "/usr/lib/python3/dist-packages/sublist3r.py", line 644, in get_csrftoken
      token = csrf_regex.findall(resp)[0]
              ~~~~~~~~~~~~~~~~~~~~~~~~^^^
  IndexError: list index out of range
  [!] Error: Google probably now is blocking our requests
  [~] Finished now the Google Enumeration ...
  [!] Error: Virustotal probably now is blocking our requests
  [-] Saving results to file: subdomains-example.com.txt
  [-] Total Unique Subdomains Found: 7
  AS207960 Test Intermediate - example.com
  www.example.com
  dev.example.com
  m.example.com
  products.example.com
  support.example.com
  m.testexample.com

  We can see the subdomains listed at the end of the command output.

  enjoy, have fun, drink water!

---

November 27, 2024

• aktsbot Installing a kernel patch on slackware

  Installing a kernel patch on slackware

  27 Nov 2024

  ---

  A good rule in the slackware wiki about upgrading kernels is to never upgrade a running kernel. To do that one's /etc/slackpkg/blacklist file would contain kernel entries like so

  kernel-generic.* kernel-huge.* kernel-modules.* kernel-source 

  Now installing a newer kernel patch becomes a hands-on affair. Here's how we'd do it.

  Download the kernel patch

  $ mkdir /tmp/slack15 $ cd /tmp/slack15 $ lftp_repo https://slackware.in/slackware/slackware64-15.0/patches/packages/linux-5.15.161/ 

  Here's the lftp_repo script file

  #!/bin/sh lftp -c "open $1 ; mirror -e -c" 

  This downloads the entire directory linux-5.15.161 from the above mirror. Feel free to substitute with your mirror and kernel of choice.

  Here's how the local copy of the directory should look like

  $ ls /tmp/slack15 ./ kernel-huge-5.15.161-x86_64-1.txz ../ kernel-huge-5.15.161-x86_64-1.txz.asc kernel-generic-5.15.161-x86_64-1.txt kernel-modules-5.15.161-x86_64-1.txt kernel-generic-5.15.161-x86_64-1.txz kernel-modules-5.15.161-x86_64-1.txz kernel-generic-5.15.161-x86_64-1.txz.asc kernel-modules-5.15.161-x86_64-1.txz.asc kernel-headers-5.15.161-x86-1.txt kernel-source-5.15.161-noarch-1.txt kernel-headers-5.15.161-x86-1.txz kernel-source-5.15.161-noarch-1.txz kernel-headers-5.15.161-x86-1.txz.asc kernel-source-5.15.161-noarch-1.txz.asc kernel-huge-5.15.161-x86_64-1.txt 

  Installing the patch

  $ cd /tmp/slack15 # installpkg *.txz 

  Make sure you use installpkg. Do not use upgradepkg as it replaces the existing package.

  Updating bootloader

  First we generate a new initrd(init ramdisk)

  # /usr/share/mkinitrd/mkinitrd_command_generator.sh -k 5.15.161 

  That should give us the command we'd need to generate the new initrd

  # mkinitrd -c -k 5.15.161 -f ext4 -r /dev/lc230vg/root \ -m redacted...:ext4 \ -C /dev/sda3 -L -u \ -o /boot/initrd-5.15.161.gz \ -h /dev/lc230vg/swap 

  Please note the -o and -h. The -o tells mkinitrd not to overwrite /boot/initrd.gz and the -h is for specifying the swap partition for hibernating.

  lilo (MBR)

  If using plain lilo, update /etc/lilo.conf by adding a new image block

  image = /boot/vmlinuz-generic-5.15.161 initrd = /boot/initrd-5.15.161.gz root = /dev/lc230vg/root label = Linux-5.15.161 read-only # Partitions should be mounted read-only for checking 

  Then update lilo

  # lilo -t # lilo -v 

  elilo (UEFI)

  If using a UEFI machine with elilo, copy over the kernel and initrd to /boot/efi

  # cp /boot/initrd-5.15.161.gz /boot/efi/EFI/Slackware/. # cp /boot/vmlinuz-generic-5.15.161 /boot/efi/EFI/Slackware/. 

  Update elilo, by adding a new image in /boot/efi/EFI/Slackware/elilo.conf

  image=vmlinuz-generic-5.15.161 label=5.15.161 initrd=initrd-5.15.161.gz read-only append="root=/dev/mapper/lc230vg-root resume=/dev/mapper/lc230vg-swap vga=normal ro" 

  Side note: For UEFI machines we don't necessarily need to use the mkinitrd command. Install the kernel patch and then run a

  # eliloconfig 

  This copies the kernel and initrd to the EFI System Partition and then updates elilo.

  Reboot and enjoy the new kernel.

  Happy Hacking & have a great day!

---

November 26, 2024

• Karthik Gst News as RSS Feeds

  “Over the weekend, I built a simple yet useful tool called gstfeed, which converts news and updates from the Indian GST portal into RSS (Atom) feeds. This makes it easy to integrate the latest information into various tools, services, and instant messaging bots. To help you get started, I’ve also set up a demo feed, which you can access through the link in the repository. Feel free to try it out and explore the possibilities!”

  I chose to use Deno for this tool as i have been following the project for a while now. Particularly the v2 release was well received by the community. The developer experience was impressive, with built-in package management, linting, formatting support. Typescript is supported out of the box! The selling point for me is the ability to compile a project into a static binary which includes the project files, dependencies & the deno runtime. Thus, making deployments & distribution easier.

---

November 12, 2024

• Bhavani Shankar The teachers who made me

  Sometimes by luck or destiny we meet extraordinary teachers. They imbue us with confidence and encourage us to learn and pursue interests that we would never do. In this process we will transform into a different people. My story is also a bit like that. So, in this post, I want to express my gratitude for all such teachers. I will address them as sir/madam like we do in our native language.

  Santosh sir

  When the funding ran out for my research project after my master’s degree, I was hopeless and lost looking for alternate career options. That's when I joined a free coding bootcamp run by Santosh. He kick-started my career in web development. Meeting a vibrant community led by him started to heal me from chronic depression. I made lots of friends.

  I was devastated to learn that he passed recently. It seems I have lost one of the few human beings who respected my choices and wanted me to have a better life than him.

  11th and 12th grade

  Rewinding back to 11th and 12th grades, I had two physics teachers. One was Subba Rao sir. (I unfortunately forgot the name of the 2nd). I still remember their mastery of physics problems and patient kindness while helping me out with problems. I enjoyed it so much that I pursued a master’s degree in physics.

  10th grade and below

  I had great math and science teachers in school. The names Vijayalakshmi madam, Phanindra Sir, Madhava Rao sir, Sarkar sir come to mind. I remember a lot of other teachers too whose names I forgot.

---

November 04, 2024

• Ravi Dwivedi Asante Kenya for a Good Time

  In September of this year, I visited Kenya to attend the State of the Map conference. I spent six nights in the capital Nairobi, two nights in Mombasa, and one night on a train. I was very happy with the visa process being smooth and quick. During the conference, I stayed at the Nairobi Transit Hotel with other attendees, with Ibtehal from Bangladesh as my roommate. I found it interesting that the shops around the hotel were grated, presumably to protect against robberies. The hotel guard had to open the lock of the hotel for us to go out at night. Further, I noticed that the banks had three layers of security. Despite this, I and Ibtehal used to hangout at a coffee shop during midnight.

  

  

  The country lies on the equator, which might give the impression of extremely hot temperatures. However, Nairobi was on the cooler side (10–25 degrees Celsius), and I found myself needing a hoodie, which I bought the next day. It also served as a nice souvenir, as it had an outline of the African map printed on it.

  I also bought a Safaricom SIM card for 100 shillings and recharged it with 1000 shillings for 8 GB internet with 5G speeds and 400 minutes talk time.

  A visit to Nairobi’s Historic Cricket Ground

  On this trip, I got a unique souvenir that can’t be purchased from the market—a cricket jersey worn in an ODI match by a player. The story goes as follows: I was roaming around the market with my friend Benson from Nairobi to buy a Kenyan cricket jersey for myself, but we couldn’t find any. So, Benson had the idea of visiting the Nairobi Gymkhana Club, which used to be Kenya’s main cricket ground. It has hosted some historic matches, including the 2003 World Cup match in which Kenya beat the mighty Sri Lankans and the record for the fastest ODI century by Shahid Afridi in just 37 balls in 1996.

  Although entry to the club was exclusively for members, I was warmly welcomed by the staff. Upon reaching the cricket ground, I met some Indian players who played in Kenyan leagues, as well as Lucas Oluoch and Dominic Wesonga, who have represented Kenya in ODIs. When I expressed interest in getting a jersey, Dominic agreed to send me pictures of his jersey. I liked his jersey and collected it from him. I gave him 2000 shillings, an amount suggested by those Indian players.

  

  

  

  

  Giraffe Center in Nairobi

  Kenya is known for its safaris and has no shortage of national parks. In fact, Nairobi is the only capital in the world with a national park. I decided not to visit one, as most of them were expensive and offered multi-day tours, and I didn’t want to spend that much time in the wildlife.

  Instead, I went to the Giraffe Center in Nairobi with Pragya and Rabina. The ticket cost 1500 Kenyan shillings (1000 Indian rupees). In Kenya, matatus - shared vans, usually decorated with portraits of famous people and play rap songs - are the most popular means of public transport. Reaching the Giraffe Center from our hotel required taking five matatus for 150 shillings and a 2 kilometer walk. The journey back was 90 shillings, suggesting that we didn’t find the most efficient route to get there. At the Giraffe Center, we fed giraffes and took photos.

  

  

  Train ride from Nairobi to Mombasa

  I wanted to visit a place outside of Nairobi. Mombasa being a coastal city and the second-largest in Kenya was a natural choice. It is 500 kilometers from the capital Nairobi. I love trains in general, so I decided to take the SGR train from Nairobi to Mombasa. I tried reserving a seat for myself from home, but found out that the train could only be booked using M-PESA. It is a mobile bank transfer system in Kenya, and I didn’t have an M-PESA account. Therefore, I could not book my ticket in advance. When I was in Kenya, I was helped by Pragya’s friend Mary for booking my ticket. It was a second-class ticket for 1500 shillings (1000 Indian rupees).

  If you are a tourist, note that local shops in Kenya can facilitate such an M-PESA transfer in exchange for cash. Your hotel may also be providing such a service, so make sure to check with them.

  The train was scheduled to depart from Nairobi at 08:00 hours in the morning and arrive in Mombasa at 14:00 hours. The security check at the station required scanning bags and having them sniffed by sniffer dogs. I also fell victim to a scam by a security official who offered to help me get my ticket printed, only to later ask me to get him some coffee, which I politely declined.

  Before boarding the train, I was treated to some stunning views at the Nairobi Terminus station. It was a seating train, but I wished it were a sleeper train, as I was sleep-deprived. The train was neat and clean, with good toilets. It reached Mombasa on time.

  

  

  Arrival in Mombasa

  

  Mombasa was a bit hotter than Nairobi, with temperatures reaching around 30 degrees Celsius. However, that’s not too hot for me, as I am used to higher temperatures in India. I had booked a hostel in the Old Town and was searching for a hitchhike from the Mombasa Terminus station. After trying for more than half an hour, I took a matatu that dropped me 3 km from my hostel for 200 shillings (140 Indian rupees). I tried to hitchhike again but couldn’t find a ride.

  I think I know why I couldn’t get a ride in both the cases. In the first case, the Mombasa Terminus was in an isolated place, so most of the vehicles were taxis or matatus while any noncommercial cars were there to pick up friends and family. If the station were in the middle of the city, there would be many more car/truck drivers passing by, thus increasing my possibilities of getting a ride. In the second case, my hostel was at the end of the city, and nobody was going towards that side. In fact, many drivers told me they would love to give me a ride, but they were going in some other direction.

  Finally, I took a tuktuk for 70 shillings to reach my hostel, Tulia Backpackers. It was 11 USD (1400 shillings) for one night. The balcony gave a nice view of the Indian Ocean. The rooms had fans, but there was no air conditioning. Each bed also had mosquito nets. The place was walking distance of the famous Fort Jesus. Mombasa has had more Islamic influence compared to Nairobi and also has many Hindu temples.

  

  

  Visiting White Sandy Beaches and Getting a Hitchhike

  Visiting Nyali beach marked my first time ever at a white sand beach. It was like 10 km from the hostel. The next day, I visited Diani Beach, which was 30 km from the hostel. Going to Diani Beach required crossing a river, for which there’s a free ferry service every few minutes, followed by taking a matatu to Ukunda and then a tuk-tuk. The journey gave me a glimpse of the beautiful countryside of Kenya.

  

  

  During my return from Diani Beach to the hostel, I was successful in hitchhiking. However, it was only a 4 km ride and not sufficient to reach Ukunda, so I tried to get another ride. When a truck stopped for me, I asked for a ride to Ukunda. Later, I learned that they were going in the same direction as me, so I got off within walking distance from my hostel. The ride was around 30 km. I also learned the difference between a truck ride and a matatu or car ride. For instance, matatus and cars are much faster and cooler due to air conditioning, while trucks tend to be warmer because they lack it. Further, the truck was stopped at many checkpoints by the police for inspections as it carried goods, which is not the case with matatus. Anyways, it was a nice experience, and I am grateful for the ride. I had a nice conversation with the truck drivers about Indian movies and my experiences in Kenya.

  

  

  Back to Nairobi

  I took the SGR train from Mombasa back to Nairobi. This time I took the night train, which departs at 22:00 hours, reaching Nairobi at around 04:00 in the morning. I could not sleep comfortably since the train only had seater seats.

  I had booked the Zarita Hotel in Nairobi and had already confirmed if they allowed early morning check-in. Usually, hotels have a fixed checkout time, say 11:00 in the morning, and you are not allowed to stay beyond that regardless of the time you checked in. But this hotel checked me in for 24 hours. Here, I paid in US dollars, and the cost was 12 USD.

  Almost Got Stuck in Kenya

  Two days before my scheduled flight from Nairobi back to India, I heard the news that the airports in Kenya were closed due to the strikes. Rabina and Pragya had their flight back to Nepal canceled that day, which left them stuck in Nairobi for two additional days. I called Sahil in India and found out during the conversation that the strike was called off in the evening. It was a big relief for me, and I was fortunate to be able to fly back to India without any changes to my plans.

  

  Experience with locals

  I had no problems communicating with Kenyans, as everyone I met knew English to an extent that could easily surpass that of big cities in India. Additionally, I learned a few words from Kenya’s most popular local language, Swahili, such as “Asante,” meaning “thank you,” “Jambo” for “hello,” and “Karibu” for “welcome.” Knowing a few words in the local language went a long way.

  I am not sure what’s up with haggling in Kenya. It wasn’t easy to bring the price of souvenirs down. I bought a fridge magnet for 200 shillings, which was the quoted price. On the other hand, it was much easier to bargain with taxis/tuktuks/motorbikes.

  I stayed at three hotels/hostels in Kenya. None of them had air conditioners. Two of the places were in Nairobi, and they didn’t even have fans in the rooms, while the one in Mombasa had only fans. All of them had good Wi-Fi, except Tulia where the internet overall was a bit shaky.

  My experience with the hotel staff was great. For instance, we requested that the Nairobi Transit Hotel cancel the included breakfast in order to reduce the room costs, but later realized that it was not a good idea. The hotel allowed us to revert and even offered one of our missing breakfasts during dinner.

  The staff at Tulia Backpackers in Mombasa facilitated the ticket payment for my train from Mombasa to Nairobi. One of the staff members also gave me a lift to the place where I could catch a matatu to Nyali Beach. They even added an extra tea bag to my tea when I requested it to be stronger.

  Food

  At the Nairobi Transit Hotel, a Spanish omelet with tea was served for breakfast. I noticed that Spanish omelette appeared on the menus of many restaurants, suggesting that it is popular in Kenya. This was my first time having this dish. The milk tea in Kenya, referred to by locals as “white tea,” is lighter than Indian tea (they don’t put a lot of tea leaves).

  

  I also sampled ugali with eggs. In Mombasa, I visited an Indian restaurant called New Chetna and had a buffet thali there twice.

  

  Tips for Exchanging Money

  In Kenya, I exchanged my money at forex shops a couple of times. I received good exchange rates for bills larger than 50 USD. For instance, 1 USD on xe.com was 129 shillings, and I got 128.3 shillings per USD (a total of 12,830 shillings) for two 50 USD notes at an exchange in Nairobi, while 127 shillings, which was the highest rate at the banks. On the other hand, for smaller bills such as a one US dollar note, I would have got 125 shillings. A passport was the only document required for the exchange, and they also provided a receipt.

  My advice for travelers would be to keep 50 USD or larger bills for exchanging into the local currency while saving the smaller US dollar bills for accommodation, as many hotels and hostels accept payment in US dollars (in addition to Kenyan shillings).

  Missed Malindi and Lamu

  There were more places on my to-visit list in Kenya. But I simply didn’t have time to cover them, as I don’t like rushing through places, especially in a foreign country where there is a chance of me underestimating the amount of time it takes during transit. I would have liked to visit at least one of Kilifi, Watamu or Malindi beaches. Further, Lamu seemed like a unique place to visit as it has no cars or motorized transport; the only options for transport are boats and donkeys. But I missed Lamu as well.

  That’s it for now. Meet you in the next one :)

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• S. Badri Introducing Convo

  Last week, I released Convo, a messaging app for feature phones (of the button variety). That has generated quite a bit of interest—and already racked up a hundred downloads within 24 hours!—so I decided to write a bit more about it here.

  

  Convo is a messaging app that adheres to the XMPP messaging standard and runs on KaiOS (and JioPhone) feature phones. That's a lot of terms, so let's break it down.

  What is KaiOS?

  

  KaiOS is a mobile operating system for budget button-operated "feature phones". While smartphones have gained popularity across the world, feature phones are still popular among

  • lower-income groups who can save by buying a budget phone
  • people from higher-income groups looking to digitally detox or reduce usage of smartphones in their lives, either by getting a "dumbphone" as a secondary or weekend device or using it to replace their smartphone entirely
  • dumbphone enthusiasts who want to practice digital minimalism and/or eschew today's trend of having one's whole life on a single device

  In 2018, KaiOS was reportedly the second-most popular mobile operating system in India (after Android). Globally, it still stands a distant third to Android and iOS, but is popular in various regions like India, Bangladesh, Tanzania, Russia, Vietnam, Brazil, parts of Africa and Europe, and the USA. Over 175 million devices have been sold to date, according to an official blog post. The popular podcasting app PodLP surpassed 10 million downloads sometime last year.

  Online, the r/KaiOS subreddit is among the top 8% of Reddit communities (now superseded by a Discord channel), with over 80,000 members.

  What is JioPhone?

  The JioPhone is a device marketed by the Indian telecom giant Jio. The JioPhone operating system is basically a rebranded KaiOS, developed in partnership with the latter, but their devices are usually locked down to the Jio network. They have also forked the KaiOS store to use their own "JioStore".

  JioPhone is the only KaiOS device officially launched in India, unless you count the Nokia 8110 Bananaphone (which was also sold in India only as a "Jio edition").

  For a while, it looked like Jio had lost interest in KaiOS, and started experimenting with budget Android phones as well as other kinds of button phones. The 'JioBharat' phone (not running KaiOS) sold over 10,000,000 units according to its parent company's annual report. Now the focus seems to be back on KaiOS with Jio releasing the JioPhone Prima 2 just a couple of months ago (September 2024).

  What is XMPP?

  XMPP is the eXtendend Messaging and Presence Protocol. It's basically an open standard for Internet messaging (although it can be extended for other uses too). This is similar to how SMTP and IMAP are standards for sending emails.

  Like email, XMPP is federated, meaning anyone can run their own XMPP-supporting service and use it to talk to other people who have joined any other XMPP-supporting service.

  Thanks to "transports" like Spectrum and Slidge, it is also possible to talk to users on other services like Signal, Discord, and Telegram through your XMPP account. That's usually not officially supported by the services on the other end, though, and tends to be a bit buggy.

  What is Convo?

  I'll just repeat the sentence from earlier, but it'll mean a lot more now that you have the context!

  Convo is a messaging app that adheres to the XMPP messaging standard and runs on KaiOS (and JioPhone) feature phones.

  Oh, and the name

  "Convo" is an informal short form for the word "conversation". It could also be seen as a diminutive form, fitting with the theme of KaiOS devices being physically "small" (but sturdy!) phones compared to the "big" smartphones.

  The name "Convo" is also a nod to the "Converse" from "ConverseJS", as well as to "Conversations", a project which is not directly related code-wise, but is the leading XMPP-compliant messaging app for Android devices.

  I am open to other names, so suggestions are welcome. If a change of name does happen, the 1.0 release (after some features like encryption are added) would be a good time to do it!

  A vaccuum to be filled

  WhatsApp has been supported on KaiOS since around mid-2018, and is one of the most popular apps on the store. However, WhatsApp recently announced in a terse notification that they're going to be dropping support for KaiOS phones by February 2025.

  This highlights one problem with centralised messaging services: as mere users, we're largely at their mercy regarding when we can use their platforms and how. This problem hits hard for operating systems like KaiOS, which, though popular, are significantly less so—and nowhere near as money-making for corporations—as major operating systems like iOS and Android. In this case, KaiOS themselves have said the decision is up to WhatsApp, and there is nothing they, KaiOS, can do about it.

  With Convo, I hope to help people break out of this cycle. Since XMPP is a decentralised, open protocol that anyone can implement, there's no large company to down the shutters whenever they get bored. As long as even a few people are interested in XMPP, the show can go on.

  That, at least, is my secondary motivation for developing Convo. My primary motivation remains to be able to use my KaiOS phone and still text my friends who use XMPP :)

  The state of chat in KaiOS today

  WhatsApp may be gone, but KaiOS still has other messaging options. Most notable are the chooj matrix client and and IRC client VM-IRC, both by farooqkz. chooj even has (highly) experimental support for voice calls, the first for a Free Software application on KaiOS.

  

  When it comes to proprietary platforms, there is a Discord client developed by Cyan, who is also developing a new Telegram client to replace the existing Telegram by arma7x. Discord is usually hostile to third-party applications and "bots", but it is where most of the KaiOS developer community currently hang out. Telegram has historically been more welcoming to third-party apps.

  Convo, and what it can do

  Though Convo is a new app, it is based on the excellent ConverseJS XMPP webclient. That means Convo should theoretically support all the features supported by ConverseJS. But since the UI had to be redone from scratch to work with the buttons and relatively small screens of KaiOS devices, only some of those features can actually be accessed.

  Until then, my recommendation would be to have a companion XMPP app installed on your desktop or laptop (or smartphone, if you have one). You can use this companion app to "set things up" and for maintenance like accepting new contact requests, while using Convo for the actual conversing.

  Things you can do with Convo

  • Sign in to your XMPP account. Only one account at a time.
  • Start a conversation with existing contacts. This includes contacts on other platforms, provided you have set up transports separately in some other XMPP client
  • Browse saved (bookmarked) group chats and rejoin them. Convo doesn't auto-join group chats opened on other devices since group chats tend to have a lot of messages, leading to performance issues. Instead you can manually join the groups you're interested in, and Convo will save them to reopen next time
  • Read and reply to incoming messages. Convo will automatically open a private conversation if someone messages you while Convo is running (but not when the app is closed)
  • Close an open conversation. If the conversation is a known contact or a bookmarked group chat, you will have the option of rejoining
  • View images shared by other people. You can't share your own images yet, though

  Things you might expect to be able to do but actually can't (yet)

  • Search through existing contacts. You have to just keep scrolling till you find them.
  • Interact with someone not in your contact list. This includes sending a message and accepting a contact request. The only exception is that, if a non-contact messages you when Convo is running, that message might appear in your conversation list and allow you to reply.
  • Join a group chat you haven't already bookmarked
  • Share images from your KaiOS device
  • Get notified when you receive a message. Convo does not yet run in the background to listen for messages. Even when the Convo app is open, it doesn't support displaying notifications in any way.
  • See unread messages. The app doesn't highlight unread messages in any way. If someone messaged you while you were offline and the conversation wasn't open, it won't even appear in your conversation list: you'll have to manually open a chat with that person to see that person's message
  • Register for and activate transports, to be able to message people on non-XMPP platforms

  Most of the above features can easily be fixed once I or someone else (maybe you?) get around to implementing the UI for it.

  End-to-end encryption

  If implemented, this would make Convo the first Free Software messaging app for KaiOS to support end-to-end encryption. (With the possible exception of WhatsApp, I believe it would be the first KaiOS messaging app to support it at all.)

  End-to-end encryption with OMEMO is already supported by ConverseJS, but due to the way it is implemented it can't be used directly by Convo.

  Specifically, Convo uses a "headless" version of ConverseJS without the UI, so that it can implement its own custom UI. Right now, the OMEMO code for ConverseJS is mixed up with the UI code: it needs to be separated into general and UI-specific parts so that the general part can go into "headless". I started working on this last year, but didn't have the time to finish.

  There's also the question of whether KaiOS can handle running the encryption/decryption algorithms. For one, this requires the JavaScript encryption libraries to run on the relatively old browser engine of KaiOS. Secondly, the KaiOS devices would need to have enough memory and processing power to be able to handle the encryption.

  OMEMO encryption can become slow on large encrypted group chats even on desktop, but I'm betting that it'll be performant on mobile for smaller conversations (especially 1-to-1 ones).

  The road to v1.0

  Now, thanks to financial contributions on Liberapay I may be able to get back to it soon! If you want to help out, check out the button below:

  

  My first priority is to set up end-to-end encryption, which will make Convo usable for everyone whose friends use encryption (which is more or less standard these days). It took me two weeks to get "almost there", but the ConverseJS code has changed in the meantime. Hopefully, another three weeks (whenever I find them) should be enough to get the ConverseJS side sorted out, after which the UI will have to be added on to Convo.

  In the meantime, I'll also aim to implement the basic usability features mentioned above (especially adding new contacts!). You can check out the tentative project board for details.

  Once that's done, Convo will be more or less usable without a companion app, and ready for version 1.0 (possibly with a new name?).

  Publishing to app stores

  Convo has already come out on the BananaHackers WebStore, the unofficial store set up by KaiOS developers and enthusiasts.

  

  The official KaiOS store currently only accepts apps that are monetised through the proprietary KaiAds SDK. This means we would have to add in-app advertisements to Convo before it can be published on the KaiStore. Also, the KaiStore version of Convo wouldn't be fully Free Software as the KaiAds part would be proprietary.

  In this case, it is probably worth the trade-off. The BananaHackers WebStore is as easy to use as the KaiStore, but only after it has been set up—which involves rooting the phone and using developer tools to set the store up. Publishing on the KaiStore would make Convo accessible to the large number of people using KaiOS who do not have the skills to set up the BananaHackers WebStore.

  JioPhone devices would be running the JioStore instead of the KaiStore. (Jio devices are also notoriously hard, if not impossible, to unlock.) According to tbrrss, creator of various KaiOS and JioPhone apps including the popular PodLP, this store is even more restrictive than the KaiStore. The JioStore disallows a lot of features, including file storage and push notifications. They also have a high quality bar, and perform QA testing on all chipsets in a process that takes many months—after submitting the package to the head of JioStore via the proprietary messaging service WhatsApp.

  Looking into the future

  Convo provides the app, but you will also need an XMPP provider for messaging. There are many free providers run by volunteer groups, such as durare.org which I am a part of.

  However, this disjoint setup would be unfamiliar to anyone using a centralised messaging platform, where the app and server are tied together and there is no question of choosing a server separately from an app.

  Quicksy and Prav address this by providing an easy onboarding process and contact autodiscovery, at the expense of having a centralised server and directory. The idea is that people can start with Quicksy or Prav, and then move on to a more customised setup when they see fit. (Thanks to the federated nature of XMPP, this won't affect their ability to talk to their contacts.)

  If Convo becomes stable enough, perhaps it could be integrated with Quicksy and/or Prav to bring the same easy onboarding to KaiOS too.

  From the other end, the Snikket project lets groups (such as families, clubs, or even small organisations) quickly start their own XMPP server, and invite whomever they want onto that. This is another project that could be integrated, allowing people to accept Snikket signup invitations through "Snikket for KaiOS".

  Software Freedom

  Perhaps this goes without saying, but Convo is Free Software. It is released under a licence that gives people the "Four Freedoms":

  • The freedom to use and run Convo without restrictions on which devices you use it on, or on how many, or for what purpose
  • The freedom to study and change the software as you see fit, including digging into the source code and making your own customisations to it (or getting someone to do it for you)
  • The freedom to share and redistribute the software with whomever you want, in private or in public
  • The freedom to modify and share your modified versions of the software—including releasing your own version of it (which would be helpful if I turn evil or disappear or something)

  These freedoms, of course, and unfortunately, do not apply to KaiAds.

  Get involved

  Convo is currently developed by one person (me) but I'm open to collaboration, both in terms of development and in terms of planning what to do next. If there is enough interest, I could move to a collective decision-making model that is being tried out by projects like Prav (that I am also involved with).

  In the meantime, here are some things you could do to help out:

  • Test run the app on your KaiOS device. You can download the latest version from the BananaHackers WebStore, the Releases page, or directly from the git repo.
  • Send me your feedback! There's this group chat about Convo that you can join from any XMPP messaging app
  • Tell other people about it. You could share this post or the main Convo repo, which is functioning as the home page for now
  • Contribute code. KaiOS apps are written using the familiar web technologies of HTML, JavaScript, and CSS, and you can (sortof) figure out things in the browser even if you don't have a KaiOS device. (It always helps to have one, though.) To get started, check out the open issues, create a new one, or contact me at the group chat mentioned above
  • Contribute money. This will help me (and/or other people) put more time into Convo. In case you missed the link earlier in the post, here is the Liberapay donation page for Convo
  • Find me on XMPP or on the Fediverse and—to quote the podcast from the photo I shared earlier—say hi. I like it when people say hi :)

  If you don't have KaiOS, you can still use XMPP through ConverseJS or other apps and services. Or, of course, you can do yourself a treat and get a KaiOS phone.

  Update: This post was updated to clarify that chooj has experimental support for audio calls (not "VoIP" as originally stated)

  Thanks to Benson for reviewing this post.

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