Tech-Thoughts

If you are building an app that uses the user’s contact book then their certain gotchas to avoid. Telephone country codes are prefix-free If a country has a country code “+91”, then no other country will get a country code like “+912” or “+913”. This scheme ensures that numbers are inherently unambiguous. Telephone numbers can have multiple representations Since most people don’t dial internationally, telecom systems implicitly assume a domestic call. So, someone dialing 612-555-1234 in the US is dialing “+1-612-555-1234”, while the same person in India is dialing “+91-612-555-1234”. Since international dialing would be more infrequent, telecoms require unique prefix numbers like “00” to distinguish whether someone is 612-555-1234 in their country or 0061-255-51234 in Austria. In some states, even the domestic area code is not explicitly required. So, a user might have stored “555-1234” as the phone number to which telecoms will implicitly prefix the user’s area code. And if the user wants to dial beyond their area, the telecom operator would require an additional “0” prefix to mark that it is an STD call. This localization has a massive implication regarding processing cleaning and normalizing phone numbers retrieved from the user’s contact book. Both country code and area code don’t contain “0”, and usually, that’s superfluous. So, while telecoms might be OK with calling or sending SMS to “0-612-555-1234”, they will treat a number like “91-0-612-555-1234” as incorrect. ...

Money serves three purpose - unit of accounting, a medium of exchange, and a store of value. Cryptocurrencies have been compared to Programmable Money. Anything programmable requires an experimentation platform for iterations and improvement. Bitcoin seems to have won the “store of value” battle. Ethereum has the developer mindshare and is the preferred experimentation platform. Multiple cryptocurrencies are still fighting the battle to be the medium of exchange. The amusing part is that every cryptocurrency startup envies Ethereum’s developer ecosystem and is trying to attract developers. But there isn’t any real value capture being the experimentation platform. A successful product has a high chance of leaving Ethereum and migrating users to its chain. The real battle, I believe, remains in becoming the medium of exchange, being the programmable Visa & Mastercard equivalent. ...

Software Engineers peak early in their career and especially in places in the San Francisco Bay area, New York, and Seattle attain accredited investor status early on in their career. Hearing stories of Jason Calacanis and Chris Sacca, many consider trying their hands-on angel investing in startups. If you are considering it, here are my few suggestions for that. Should you do it Angel investing, just like many other exotic ventures such as buying arts and vintage coins, is optional. It is much more safe to make money by investing in publicly listed companies. So, don’t do it for money. Find a better reason to do it. For me, the opportunity to connect with other entrepreneurs makes it worthwhile. ...

Why Tech In the past decade, interest among MBA grads towards tech companies has drastically gone up. If you are one of those, take a pause and ask yourself “why”. Of course, there are upsides; the tech sector is growing faster, pays well, has a much better work-life balance than finance, private equity, or consulting. But at the same time, do remember that you spend almost 50% of your waking hours at your workplace, so you must as well enjoy it. If you enjoy flashy presentations, regular travel, or an opportunity to think about big M&A deals, then these things come much earlier in your career on the east coast than that on the west. ...

Background There are three major types of financial exchanges Stocks and bonds Commodity exchange Foreign exchange (Forex)

For 6-months, this website was compromised. I am not sure what exactly happened, but it was most likely password-reuse, which lend itself to this problem. The problem became apparent when I first noticed an unusual link to a ride-sharing service. Later, I saw more of those links. That’s when I realized that I couldn’t merely sit and scan every blog post manually and decided to write a small interactive link checker tool. This tool whitelists the starting domain and allows you to whitelist URLs on a per-domain basis. The whitelist is persisted at the end of execution and will be used next time you use the tool. ...

Earlier, the Software world was rigidly divided between closed and open-source software. Microsoft Windows is closed-source, GNU/Linux is open-source. Microsoft Office and Lotus Notes are closed-source, LibreOffice is open-source. Turbo C++ is closed-source, and GCC is open-source. But now, a new class of software products has emerged whose core is open-source, but still, the open-source software is of limited use. One model is to offer some critical and useful functionality in a closed-source layer via a managed service in AWS/GCP/Azure, for example, Redis is open-source, but useful modules on top of it are not. Another model is to use licensing gimmickry, for example, MongoDB is licensed under SSPL which requires that if anyone offers MongoDB as a service, then the source code of the full service must be published under this license. The third approach is to make the core software open-source but make it dependent on closed-source cloud services. For example, the node package manager (npm) is open-source, but a closed source company owns the default npm registry. Android is open-source, but most day-to-day application ranging from Google Maps to Google Music are closed-source. Now onwards, rather than calling such software open-source, we should call them closeum. ...

Consider this email, And now consider this one, Hi Ashish, You signed up for the Orchard beta not too long ago, and we’re excited to finally send you an invite! ( Just to jog your memory, Orchard helps you make the most of your relationships, keeping you up to date on where you’re spending your time and who you need to catch up with. It’s somewhere between a personal CRM and a todo list for your connections.) [Emphasis mine] ...

All cryptocurrencies are eventually tied to a “private” key. You lose this key, and the funds are gone, forever. Millions worth of bitcoins have disappeared from the circulation due to lost keys. You can memorize the key by mapping it into passphrase consisting of memorizable words but if you forget that, like many others, the coins are unrecoverable. An alternative is to trust a centralized service like Coinbase, but then all the benefits of investing in a decentralized currency are gone. Lastly, one can use a hardware wallet, but again, if you lose the wallet, the key is lost. If you keep the key on your device, then a malware might target and try to steal it someday. Thus, even if you are bullish on cryptocurrencies, there are no good decentralized ways of holding a significant chunk of your net worth in cryptocurrencies. ...

When the code runs on your servers, you have much more control over the “context” in which it runs. On the mobile devices, the device OS and the user control the context. This difference leads to some subtle implications. One significant set of differences comes from the lack of control of the platform. For server-side code, one can choose from a wide array of languages. For the mobile code, however, the best choice would almost always be the one dictated by the platform - Java/Kotlin on Android and Objective-C/Swift on iOS. Further, for the server-side where one can stick to a particular version of the language. In the case of mobile, the platform controls the language version. Same goes regarding the hardware choices - one can choose to use different types of server machines specialized in handling those jobs, eg. GPUs for math-intensive computes. While for the mobile-code, one had to write a good enough fallback to support a wide-enough set the devices. Similarly, the server-side has to rarely worry about the server killing a running process while it is normal for mobile OSes to kill backgrounded processes eventually. ...