More on Technology

Gajus Kuizinas
3 years ago
How a few lines of code were able to eliminate a few million queries from the database
I was entering tens of millions of records per hour when I first published Slonik PostgreSQL client for Node.js. The data being entered was usually flat, making it straightforward to use INSERT INTO ... SELECT * FROM unnset() pattern. I advocated the unnest approach for inserting rows in groups (that was part I).
However, today I’ve found a better way: jsonb_to_recordset.
jsonb_to_recordsetexpands the top-level JSON array of objects to a set of rows having the composite type defined by an AS clause.
jsonb_to_recordset allows us to query and insert records from arbitrary JSON, like unnest. Since we're giving JSON to PostgreSQL instead of unnest, the final format is more expressive and powerful.
SELECT *
FROM json_to_recordset('[{"name":"John","tags":["foo","bar"]},{"name":"Jane","tags":["baz"]}]')
AS t1(name text, tags text[]);
name | tags
------+-----------
John | {foo,bar}
Jane | {baz}
(2 rows)Let’s demonstrate how you would use it to insert data.
Inserting data using json_to_recordset
Say you need to insert a list of people with attributes into the database.
const persons = [
{
name: 'John',
tags: ['foo', 'bar']
},
{
name: 'Jane',
tags: ['baz']
}
];You may be tempted to traverse through the array and insert each record separately, e.g.
for (const person of persons) {
await pool.query(sql`
INSERT INTO person (name, tags)
VALUES (
${person.name},
${sql.array(person.tags, 'text[]')}
)
`);
}It's easier to read and grasp when working with a few records. If you're like me and troubleshoot a 2M+ insert query per day, batching inserts may be beneficial.
What prompted the search for better alternatives.
Inserting using unnest pattern might look like this:
await pool.query(sql`
INSERT INTO public.person (name, tags)
SELECT t1.name, t1.tags::text[]
FROM unnest(
${sql.array(['John', 'Jane'], 'text')},
${sql.array(['{foo,bar}', '{baz}'], 'text')}
) AS t1.(name, tags);
`);You must convert arrays into PostgreSQL array strings and provide them as text arguments, which is unsightly. Iterating the array to create slices for each column is likewise unattractive.
However, with jsonb_to_recordset, we can:
await pool.query(sql`
INSERT INTO person (name, tags)
SELECT *
FROM jsonb_to_recordset(${sql.jsonb(persons)}) AS t(name text, tags text[])
`);In contrast to the unnest approach, using jsonb_to_recordset we can easily insert complex nested data structures, and we can pass the original JSON document to the query without needing to manipulate it.
In terms of performance they are also exactly the same. As such, my current recommendation is to prefer jsonb_to_recordset whenever inserting lots of rows or nested data structures.

Tom Smykowski
2 years ago
CSS Scroll-linked Animations Will Transform The Web's User Experience
We may never tap again in ten years.
I discussed styling websites and web apps on smartwatches in my earlier article on W3C standardization.
The Parallax Chronicles
Section containing examples and flying objects
Another intriguing Working Draft I found applies to all devices, including smartphones.
These pages may have something intriguing. Take your time. Return after scrolling:
What connects these three pages?
JustinWick at English Wikipedia • CC-BY-SA-3.0
Scroll-linked animation, commonly called parallax, is the effect.
WordPress theme developers' quick setup and low-code tools made the effect popular around 2014.
Parallax: Why Designers Love It
The chapter that your designer shouldn't read
Online video playback required searching, scrolling, and clicking ten years ago. Scroll and click four years ago.
Some video sites let you swipe to autoplay the next video from an endless list.
UI designers create scrollable pages and apps to accommodate the behavioral change.
Web interactivity used to be mouse-based. Clicking a button opened a help drawer, and hovering animated it.
However, a large page with more material requires fewer buttons and less interactiveness.
Designers choose scroll-based effects. Design and frontend developers must fight the trend but prepare for the worst.
How to Create Parallax
The component that you might want to show the designer
JavaScript-based effects track page scrolling and apply animations.
Javascript libraries like lax.js simplify it.
Using it needs a lot of human mathematical and physical computations.
Your asset library must also be prepared to display your website on a laptop, television, smartphone, tablet, foldable smartphone, and possibly even a microwave.
Overall, scroll-based animations can be solved better.
CSS Scroll-linked Animations
CSS makes sense since it's presentational. A Working Draft has been laying the groundwork for the next generation of interactiveness.
The new CSS property scroll-timeline powers the feature, which MDN describes well.
Before testing it, you should realize it is poorly supported:
Firefox 103 currently supports it.
There is also a polyfill, with some demo examples to explore.
Summary
Web design was a protracted process. Started with pages with static backdrop images and scrollable text. Artists and designers may use the scroll-based animation CSS API to completely revamp our web experience.
It's a promising frontier. This post may attract a future scrollable web designer.
Ps. I have created flashcards for HTML, Javascript etc. Check them out!

Shalitha Suranga
3 years ago
The Top 5 Mathematical Concepts Every Programmer Needs to Know
Using math to write efficient code in any language
Programmers design, build, test, and maintain software. Employ cases and personal preferences determine the programming languages we use throughout development. Mobile app developers use JavaScript or Dart. Some programmers design performance-first software in C/C++.
A generic source code includes language-specific grammar, pre-implemented function calls, mathematical operators, and control statements. Some mathematical principles assist us enhance our programming and problem-solving skills.
We all use basic mathematical concepts like formulas and relational operators (aka comparison operators) in programming in our daily lives. Beyond these mathematical syntaxes, we'll see discrete math topics. This narrative explains key math topics programmers must know. Master these ideas to produce clean and efficient software code.
Expressions in mathematics and built-in mathematical functions
A source code can only contain a mathematical algorithm or prebuilt API functions. We develop source code between these two ends. If you create code to fetch JSON data from a RESTful service, you'll invoke an HTTP client and won't conduct any math. If you write a function to compute the circle's area, you conduct the math there.
When your source code gets more mathematical, you'll need to use mathematical functions. Every programming language has a math module and syntactical operators. Good programmers always consider code readability, so we should learn to write readable mathematical expressions.
Linux utilizes clear math expressions.
Inbuilt max and min functions can minimize verbose if statements.
How can we compute the number of pages needed to display known data? In such instances, the ceil function is often utilized.
import math as m
results = 102
items_per_page = 10
pages = m.ceil(results / items_per_page)
print(pages)Learn to write clear, concise math expressions.
Combinatorics in Algorithm Design
Combinatorics theory counts, selects, and arranges numbers or objects. First, consider these programming-related questions. Four-digit PIN security? what options exist? What if the PIN has a prefix? How to locate all decimal number pairs?
Combinatorics questions. Software engineering jobs often require counting items. Combinatorics counts elements without counting them one by one or through other verbose approaches, therefore it enables us to offer minimum and efficient solutions to real-world situations. Combinatorics helps us make reliable decision tests without missing edge cases. Write a program to see if three inputs form a triangle. This is a question I commonly ask in software engineering interviews.
Graph theory is a subfield of combinatorics. Graph theory is used in computerized road maps and social media apps.
Logarithms and Geometry Understanding
Geometry studies shapes, angles, and sizes. Cartesian geometry involves representing geometric objects in multidimensional planes. Geometry is useful for programming. Cartesian geometry is useful for vector graphics, game development, and low-level computer graphics. We can simply work with 2D and 3D arrays as plane axes.
GetWindowRect is a Windows GUI SDK geometric object.
High-level GUI SDKs and libraries use geometric notions like coordinates, dimensions, and forms, therefore knowing geometry speeds up work with computer graphics APIs.
How does exponentiation's inverse function work? Logarithm is exponentiation's inverse function. Logarithm helps programmers find efficient algorithms and solve calculations. Writing efficient code involves finding algorithms with logarithmic temporal complexity. Programmers prefer binary search (O(log n)) over linear search (O(n)). Git source specifies O(log n):
Logarithms aid with programming math. Metas Watchman uses a logarithmic utility function to find the next power of two.
Employing Mathematical Data Structures
Programmers must know data structures to develop clean, efficient code. Stack, queue, and hashmap are computer science basics. Sets and graphs are discrete arithmetic data structures. Most computer languages include a set structure to hold distinct data entries. In most computer languages, graphs can be represented using neighboring lists or objects.
Using sets as deduped lists is powerful because set implementations allow iterators. Instead of a list (or array), store WebSocket connections in a set.
Most interviewers ask graph theory questions, yet current software engineers don't practice algorithms. Graph theory challenges become obligatory in IT firm interviews.
Recognizing Applications of Recursion
A function in programming isolates input(s) and output(s) (s). Programming functions may have originated from mathematical function theories. Programming and math functions are different but similar. Both function types accept input and return value.
Recursion involves calling the same function inside another function. In its implementation, you'll call the Fibonacci sequence. Recursion solves divide-and-conquer software engineering difficulties and avoids code repetition. I recently built the following recursive Dart code to render a Flutter multi-depth expanding list UI:
Recursion is not the natural linear way to solve problems, hence thinking recursively is difficult. Everything becomes clear when a mathematical function definition includes a base case and recursive call.
Conclusion
Every codebase uses arithmetic operators, relational operators, and expressions. To build mathematical expressions, we typically employ log, ceil, floor, min, max, etc. Combinatorics, geometry, data structures, and recursion help implement algorithms. Unless you operate in a pure mathematical domain, you may not use calculus, limits, and other complex math in daily programming (i.e., a game engine). These principles are fundamental for daily programming activities.
Master the above math fundamentals to build clean, efficient code.
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Victoria Kurichenko
3 years ago
Here's what happened after I launched my second product on Gumroad.
One-hour ebook sales, affiliate relationships, and more.
If you follow me, you may know I started a new ebook in August 2022.
Despite publishing on this platform, my website, and Quora, I'm not a writer.
My writing speed is slow, 2,000 words a day, and I struggle to communicate cohesively.
In April 2022, I wrote a successful guide on How to Write Google-Friendly Blog Posts.
I had no email list or social media presence. I've made $1,600+ selling ebooks.
Evidence:
My first digital offering isn't a book.
It's an actionable guide with my tried-and-true process for writing Google-friendly content.
I'm not bragging.
Established authors like Tim Denning make more from my ebook sales with one newsletter.
This experience taught me writing isn't a privilege.
Writing a book and making money online doesn't require expertise.
Many don't consult experts. They want someone approachable.
Two years passed before I realized my own limits.
I have a brain, two hands, and Internet to spread my message.
I wrote and published a second ebook after the first's success.
On Gumroad, I released my second digital product.
Here's my complete Gumroad evaluation.
Gumroad is a marketplace for content providers to develop and sell sales pages.
Gumroad handles payments and client requests. It's helpful when someone sends a bogus payment receipt requesting an ebook (actual story!).
You'll forget administrative concerns after your first ebook sale.
After my first ebook sale, I did this: I made additional cash!
After every sale, I tell myself, "I built a new semi-passive revenue source."
This thinking shift helps me become less busy while increasing my income and quality of life.
Besides helping others, folks sell evergreen digital things to earn passive money.
It's in my second ebook.
I explain how I built and sold 50+ copies of my SEO writing ebook without being an influencer.
I show how anyone can sell ebooks on Gumroad and automate their sales process.
This is my ebook.
After publicizing the ebook release, I sold three copies within an hour.
Wow, or meh?
I don’t know.
The answer is different for everyone.
These three sales came from a small email list of 40 motivated fans waiting for my ebook release.
I had bigger plans.
I'll market my ebook on Medium, my website, Quora, and email.
I'm testing affiliate partnerships this time.
One of my ebook buyers is now promoting it for 40% commission.
Become my affiliate if you think your readers would like my ebook.
My ebook is a few days old, but I'm interested to see where it goes.
My SEO writing book started without an email list, affiliates, or 4,000 website visitors. I've made four figures.
I'm slowly expanding my communication avenues to have more impact.
Even a small project can open doors you never knew existed.
So began my writing career.
In summary
If you dare, every concept can become a profitable trip.
Before, I couldn't conceive of creating an ebook.
How to Sell eBooks on Gumroad is my second digital product.
Marketing and writing taught me that anything can be sold online.

obimy.app
3 years ago
How TikTok helped us grow to 6 million users
This resulted to obimy's new audience.
Hi! obimy's official account. Here, we'll teach app developers and marketers. In 2022, our downloads increased dramatically, so we'll share what we learned.
obimy is what we call a ‘senseger’. It's a new method to communicate digitally. Instead of text, obimy users connect through senses and moods. Feeling playful? Flirt with your partner, pat a pal, or dump water on a classmate. Each feeling is an interactive animation with vibration. It's a wordless app. App Store and Google Play have obimy.
We had 20,000 users in 2022. Two to five thousand of them opened the app monthly. Our DAU metric was 500.
We have 6 million users after 6 months. 500,000 individuals use obimy daily. obimy was the top lifestyle app this week in the U.S.
And TikTok helped.
TikTok fuels obimys' growth. It's why our app exploded. How and what did we learn? Our Head of Marketing, Anastasia Avramenko, knows.
our actions prior to TikTok
We wanted to achieve product-market fit through organic expansion. Quora, Reddit, Facebook Groups, Facebook Ads, Google Ads, Apple Search Ads, and social media activity were tested. Nothing worked. Our CPI was sometimes $4, so unit economics didn't work.
We studied our markets and made audience hypotheses. We promoted our goods and studied our audience through social media quizzes. Our target demographic was Americans in long-distance relationships. I designed quizzes like Test the Strength of Your Relationship to better understand the user base. After each quiz, we encouraged users to download the app to enhance their connection and bridge the distance.
We got 1,000 responses for $50. This helped us comprehend the audience's grief and coping strategies (aka our rivals). I based action items on answers given. If you can't embrace a loved one, use obimy.
We also tried Facebook and Google ads. From the start, we knew it wouldn't work.
We were desperate to discover a free way to get more users.
Our journey to TikTok
TikTok is a great venue for emerging creators. It also helped reach people. Before obimy, my TikTok videos garnered 12 million views without sponsored promotion.
We had to act. TikTok was required.
I wasn't a TikTok user before obimy. Initially, I uploaded promotional content. Call-to-actions appear strange next to dancing challenges and my money don't jiggle jiggle. I learned TikTok. Watch TikTok for an hour was on my to-do list. What a dream job!
Our most popular movies presented the app alongside text outlining what it does. We started promoting them in Europe and the U.S. and got a 16% CTR and $1 CPI, an improvement over our previous efforts.
Somehow, we were expanding. So we came up with new hypotheses, calls to action, and content.
Four months passed, yet we saw no organic growth.
Russia attacked Ukraine.
Our app aimed to be helpful. For now, we're focusing on our Ukrainian audience. I posted sloppy TikToks illustrating how obimy can help during shelling or air raids.
In two hours, Kostia sent me our visitor count. Our servers crashed.
Initially, we had several thousand daily users. Over 200,000 users joined obimy in a week. They posted obimy videos on TikTok, drawing additional users. We've also resumed U.S. video promotion.
We gained 2,000,000 new members with less than $100 in ads, primarily in the U.S. and U.K.
TikTok helped.
The figures
We were confident we'd chosen the ideal tool for organic growth.
Over 45 million people have viewed our own videos plus a ton of user-generated content with the hashtag #obimy.
About 375 thousand people have liked all of our individual videos.
The number of downloads and the virality of videos are directly correlated.
Where are we now?
TikTok fuels our organic growth. We post 56 videos every week and pay to promote viral content.
We use UGC and influencers. We worked with Universal Music Italy on Eurovision. They offered to promote us through their million-follower TikTok influencers. We thought their followers would improve our audience, but it didn't matter. Integration didn't help us. Users that share obimy videos with their followers can reach several million views, which affects our download rate.
After the dust settled, we determined our key audience was 13-18-year-olds. They want to express themselves, but it's sometimes difficult. We're searching for methods to better engage with our users. We opened a Discord server to discuss anime and video games and gather app and content feedback.
TikTok helps us test product updates and hypotheses. Example: I once thought we might raise MAU by prompting users to add strangers as friends. Instead of asking our team to construct it, I made a TikTok urging users to share invite URLs. Users share links under every video we upload, embracing people worldwide.
Key lessons
Don't direct-sell. TikTok isn't for Instagram, Facebook, or YouTube promo videos. Conventional advertisements don't fit. Most users will swipe up and watch humorous doggos.
More product videos are better. Finally. So what?
Encourage interaction. Tagging friends in comments or making videos with the app promotes it more than any marketing spend.
Be odd and risqué. A user mistakenly sent a French kiss to their mom in one of our most popular videos.
TikTok helps test hypotheses and build your user base. It also helps develop apps. In our upcoming blog, we'll guide you through obimy's design revisions based on TikTok. Follow us on Twitter, Instagram, and TikTok.

Keagan Stokoe
3 years ago
Generalists Create Startups; Specialists Scale Them
There’s a funny part of ‘Steve Jobs’ by Walter Isaacson where Jobs says that Bill Gates was more a copier than an innovator:
“Bill is basically unimaginative and has never invented anything, which is why I think he’s more comfortable now in philanthropy than technology. He just shamelessly ripped off other people’s ideas….He’d be a broader guy if he had dropped acid once or gone off to an ashram when he was younger.”
Gates lacked flavor. Nobody ever got excited about a Microsoft launch, despite their good products. Jobs had the world's best product taste. Apple vs. Microsoft.
A CEO's core job functions are all driven by taste: recruiting, vision, and company culture all require good taste. Depending on the type of company you want to build, know where you stand between Microsoft and Apple.
How can you improve your product judgment? How to acquire taste?
Test and refine
Product development follows two parallel paths: the ‘customer obsession’ path and the ‘taste and iterate’ path.
The customer obsession path involves solving customer problems. Lean Startup frameworks show you what to build at each step.
Taste-and-iterate doesn't involve the customer. You iterate internally and rely on product leaders' taste and judgment.
Creative Selection by Ken Kocienda explains this method. In Creative Selection, demos are iterated and presented to product leaders. Your boss presents to their boss, and so on up to Steve Jobs. If you have good product taste, you can be a panelist.
The iPhone follows this path. Before seeing an iPhone, consumers couldn't want one. Customer obsession wouldn't have gotten you far because iPhone buyers didn't know they wanted one.
In The Hard Thing About Hard Things, Ben Horowitz writes:
“It turns out that is exactly what product strategy is all about — figuring out the right product is the innovator’s job, not the customer’s job. The customer only knows what she thinks she wants based on her experience with the current product. The innovator can take into account everything that’s possible, but often must go against what she knows to be true. As a result, innovation requires a combination of knowledge, skill, and courage.“
One path solves a problem the customer knows they have, and the other doesn't. Instead of asking a person what they want, observe them and give them something they didn't know they needed.
It's much harder. Apple is the world's most valuable company because it's more valuable. It changes industries permanently.
If you want to build superior products, use the iPhone of your industry.
How to Improve Your Taste
I. Work for a company that has taste.
People with the best taste in products, markets, and people are rewarded for building great companies. Tasteful people know quality even when they can't describe it. Taste isn't writable. It's feel-based.
Moving into a community that's already doing what you want to do may be the best way to develop entrepreneurial taste. Most company-building knowledge is tacit.
Joining a company you want to emulate allows you to learn its inner workings. It reveals internal patterns intuitively. Many successful founders come from successful companies.
Consumption determines taste. Excellence will refine you. This is why restauranteurs visit the world's best restaurants and serious painters visit Paris or New York. Joining a company with good taste is beneficial.
2. Possess a wide range of interests
“Edwin Land of Polaroid talked about the intersection of the humanities and science. I like that intersection. There’s something magical about that place… The reason Apple resonates with people is that there’s a deep current of humanity in our innovation. I think great artists and great engineers are similar, in that they both have a desire to express themselves.” — Steve Jobs
I recently discovered Edwin Land. Jobs modeled much of his career after Land's. It makes sense that Apple was inspired by Land.
A Triumph of Genius: Edwin Land, Polaroid, and the Kodak Patent War notes:
“Land was introverted in person, but supremely confident when he came to his ideas… Alongside his scientific passions, lay knowledge of art, music, and literature. He was a cultured person growing even more so as he got older, and his interests filtered into the ethos of Polaroid.”
Founders' philosophies shape companies. Jobs and Land were invested. It showed in the products their companies made. Different. His obsession was spreading Microsoft software worldwide. Microsoft's success is why their products are bland and boring.
Experience is important. It's probably why startups are built by generalists and scaled by specialists.
Jobs combined design, typography, storytelling, and product taste at Apple. Some of the best original Mac developers were poets and musicians. Edwin Land liked broad-minded people, according to his biography. Physicist-musicians or physicist-photographers.
Da Vinci was a master of art, engineering, architecture, anatomy, and more. He wrote and drew at the same desk. His genius is remembered centuries after his death. Da Vinci's statue would stand at the intersection of humanities and science.
We find incredibly creative people here. Superhumans. Designers, creators, and world-improvers. These are the people we need to navigate technology and lead world-changing companies. Generalists lead.
