BC SOCIAL MEDIA
Saved by @CodyyyGardner

It makes me smile every time I notice IGListKit at work in Instagram. We put a lot of work into making and improving it. Proud to see it holding up 4 years later.

🧵 with some memories on how it was built:

 At Instagram, product work slowed around the holidays, so we used the time to pay down tech debt. In winter 2014 I reviewed a +12k line refactor from UITableView to UICollectionView.

We recently dropped iOS 5 so we could use the new 6+ APIs without backwards compatibility.
That review taught me a lot about UICV: data sources should mutate in one place else risk out-of-sync exceptions, the first view layout may reloadData, sticky headers make good perf hard, and many more UICV tidbits
We used reloadData for everything and it worked, for the most part.

Except two things bugged the hell out of me:

1. No animated changes (duh)
2. Images could flicker and the like animation could cancel
I dug into the latter and learned that if you reloadData, every cell on screen gets reused. So even if nothing in the UI changes, you still reuse (or init) cells, bind data, set images, etc. that’s a lot of work!
When you liked a post, we’d call reloadData. Since all cells are replaced: we had to track the liked row, reload, and THEN perform the like animation. 😓

If something triggered another reload after the animation started, the cell cancelled the animation (thus the UI bug)
The image flickering issue was simpler:

When an image cell is reused set the background to grey, async load the image (cache or network), set the image. The async time between reuse and fetch/set from cache is where the flicker came from.
(@ryanolsonk solved the image flicker with an insanely clever “weak image cache” design. It’s a great interview question 😉 )
This all got me thinking: what if we only updated cells when the data changes? This general idea was gaining traction (ahem, React): bind data to views, and diff the data on change to only rebind changed data+views.

Enter UICV performBatchUpdates
Using the principle of only updating the data source in one place, I could diff the from/to data and use UICVs APIs to insert/delete/reload/move. Anything unchanged wouldn’t get touched!

So how the hell do I write a diffing algorithm? I literally had never done this.
I researched several algos: rsync, Myers, react...

I settled on Paul Heckel’s https://t.co/jpxuHNlpXg

Why?

1. It’s output matched UICV’s APIs: inserts, deletes, updates, and moves
2. There were example implementations I could actually understand
A pivotal decision was how we define identity and equality. I wanted to piggy-back off NSObject’s -hash and -isEqual: methods to spare our engineers having to write/understand diffing concepts.
@ryanolsonk convinced me I was wrong bc writing proper -hash is complex https://t.co/4PgDCykAna

Foundation hashes can collide
https://t.co/h9eVHO342U

Or are too basic for diffing
https://t.co/Pp0eVFRS5e https://t.co/ZNPJnXlXa4
We settled on a hybrid API: a protocol with custom identifier and -isEqual: We later scrapped the NSObject tricks as they were easy to abuse & forget, resulting in crashes.
Fun fact: the library was originally called “IGStoryKit” but my director hated that so we renamed it. Glad we did, guess what launched 6 months later? 🤪
Over the next several months, @jesse_squires and I refactored probably 20k lines so that we could run our new infra alongside the old one. This let us safely A/B test performance before rolling out.
We started with single-item feeds but quickly moved to support the main feed. Main feed was scary (we were starting to run ads 😬) but if we could replace feed, then the rest of the app would fall in line.
@ocrickard and I spent a couple months investigating crashes and tuning performance. I learned a lot about ObjC++ during this time (unordered_map was waaaay faster than NSDictionary for our diffing).
We ended up filing 4 UICV radars from all this investigation! Some have been closed

https://t.co/BACvyI2l08+
When everything was fixed, we launched. I spent a year advocating the eng org help refactor and deprecate the old infra. It came down to the profile view. I rolled up my sleeves and did it myself. It was TOUGH

With profile done, I submitted a -12k change to remove the old infra.
From the start we wanted to open source the library. It ended up being a lot of paper work and internal politics, but we did it. Forever grateful to @jesse_squires for setting the project up for success and @mikeyk for having our back.
We started writing the library in late 2015, launched feed summer of 2016, and deleted the old infra in early 2017.

Throughout this the eng team 10x’d and users 4x’d, we launched tons of products (Stories!), IG opened a NY office, UICV got diffable data sources, and more.
After we launched 4y ago I calc’d our diffing algorithm executes over 40,000 times a second. I can’t imagine what that is now!
Building IGListKit was a career’s-worth of learning packed into a couple years.

I’m proud that it’s still powering Instagram today, but I’m looking forward to learning about what replaces it.

More from Social media

KP
KP
@thisiskp_
10 ridiculously simple tips I wish I knew about building an audience when I first started:

I mostly winged it 🤫

Let me share my lessons so you don't have to:

(a thread 🧵)

1/ Switch from being a consumer to a creator

If your default is opening social media and binging on updates from others, there's a problem. The world needs to know what YOU can offer, and I believe everyone can add value. So first, switch to intentionally becoming a creator.

2/ Start very small and build "Atomic habits"

Most beginner creators people aim too far high and crash. It never works for me. Instead choose tiny habits like 2 tweets a day in the morning. Or 1 video for Youtube. Or 1 short essay each day on Substack. Optimize for consistency.

3/ Pick one social platform to create and stick with it

What comes naturally to you? Writing your thoughts, choose Twitter. Editing interesting footage and layering a voice-over? Choose Youtube. Short essays? Choose Substack. Pick one and stick with it for at last 1 month.

4/ Find your niche

Don't focus on big bold segments with hundreds of active prolific creators already fishing. Find specific audiences and move towards them.

I was a no-code maker in 2018 so that niche came naturally. Later, I expanded to the community niche. Now #buildinpublic
SOCIAL MEDIA , CONTENT
David Kadavy
David Kadavy
@kadavy
An annoying feature in an "influencer" career is that it seems like you'll be much better off if you're "nice" to everyone.

You can always collaborate or "swap." You don't like their work, or maybe even them as a person, but gosh can you pass up this opportunity?

This might be an illusion. You're probably better off ignoring everyone and focusing on your own work.

Then again, it might not be an illusion. It's something I've noticed with successful Hollywood people. They're so damn nice. Either they are extremely agreeable people, or they have to fake it.

However, it's a much more people-oriented business than publishing.
SOCIAL MEDIA
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Sunshiny
Sunshiny
@sunnshiiny
As we wait for the transition of power from despot to democrat, Facebook (Zuckerberg) has taken it upon itself to aid in the obstruction of that power transfer, facilitation of an insurrection narrative and disregard for the will of the American electorate.


In other words, the Social Media monopoly Facebook commands globally has gone full fascist in an attempt to preserve the corrupt and criminal hold on power by Republicans and Trump Administration.

Aiding and abetting a coup d’état.

As if there weren’t enough other reasons to dismantle Facebook’s monopoly, Zuckerberg is playing his cards and revealing clearly that Cambridge Analytica election interference was not just a onetime anomaly, but is now a feature of Facebook’s business model.

Megalomaniac Marc has now revealed the true colours of Fascist Facebook.

Facebook is a weapon to manipulate the masses. A tool to carry out disinformation campaigns with impunity.

And the response of the left... is to delete their Facebook account.

As if the deletion of a Facebook account will do anything. It might send a message that your virtues are principled, your morality superior. But it enables the weapon to be continued to gaslight and manipulate the electorate.

An inherent flaw in the left’s critical thinking.
SOCIAL MEDIA
Snapchat
Snapchat
@Snapchat
Enter the thread if you dare. 😈

We’re counting down 13 of the best ways to Halloween on Snapchat. First up – matching Lens costumes for you and your pet.

https://t.co/J0Zn7CfM1q


Tis the season to slay some ghouls. Grab some friends and dive in to Zombie Rescue Squad from @PikPokGames. How long can you survive?

https://t.co/FC9dvafUiV


Is it even Halloween if you're not FREAKED OUT? Scare yourself silly with a Dead of Night S1 rewatch.

https://t.co/LtoE7yHgaG


Be careful! Things aren’t always what they seem. Our Lenses start off cute, but are filled with spooky surprises!

https://t.co/xq45JlYeQ7


Craving candy early? Our new stickers were made to satisfy your sweet tooth.
SOCIAL MEDIA
Rudy Havenstein, Check out the fact-checkers.
Rudy Havenstein, Check...
@RudyHavenstein
So let's check in on "Newsguard," one of the Orwellian groups (e.g., The Atlantic Council) that totally reliable sites like @voxdotcom and @axios use to decide what is "Unreliable" and "fight disinformation."

One example:

OK, so "The Daily Wire" and "https://t.co/oEa89coNak" are unreliable. Fair enough, maybe they are (I don't use either one of them).

So let's look into one of our new official arbiters of "reliability," Newsguard!

What's their advisory board look like?

https://t.co/5N8op70VE1


OK, so maybe a few names jumped out at you immediately, like, oh I don't know, (Ret.) General Michael Hayden, former Director of the CIA AND former Director of the National Security Agency in the run-up to the Iraq War in 2003! Google him, he's famous!


Newsguard is all about "seeing who's behind each site," (like how Michael Hayden is behind Newsguard?)

All they want to do is fight "misinformation." That's laudable, right?

Also, Newsguard has a "24/7 rapid response SWAT TEAM!!"

So cool!
https://t.co/EDN3UXvBR9


Ok, I'm not a journalist or a former CIA director, so I have no idea what's true or not unless someone tells me, so hey, Columbia Journalism Review - what do you think of Newsguard Advisory Board Member Michael Hayden?
SOCIAL MEDIA

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Corey Haines \U0001f4a1
Corey Haines 💡...
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I think I'm giving up on mainstream marketing content.

I'm giving up on social media consumption too.

So little substance.

Need to devote more time doing. More time creating.

Who needs another "5 ways to boost growth" post? I click and am disappointed every time. Not again.

I don't want to poop on content marketing, but marketers need to step it up.

Or at least, founders need to know that doing something is not always better than doing nothing.

Why is content marketing not as effective as it used to be? An innumerable amount of factors...

But one things for damn sure.

Things have to change.

Two of the chief sins:
1. Unoriginal research/story/study/etc
2. Not having anything more to add that's meaningful

Why blog/podcast/vlog/etc about something that's already been said? Already been done?

Do we really need another interview with founder of x hot startup? Do we really need another ultimate guide about facebook ads?

Not all content is like this...

Sometimes, you get an occasional piece that truly leaves you better off than you were before. That doesn't make you want to skim.

An original case study. A first time interview with a founder. An honest account of an experiment. An explanation of a change, shift, or realization.
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GunduHuduga| \u0c97\u0cc1\u0c82\u0ca1\u0cc1 \u0cb9\u0cc1\u0ca1\u0cc1\u0c97|\U0001f549
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#SatiSavitri #RealLifeExperiences #BharatDarshana

Bharat Darshana publishes a small monthly magazine which has some very interesting puranic anecdotes and snippets.

When I picked up this month's magazine, I was intrigued by a story which I want to share as below

1/

This is a real-life incident as narrated by Prof. Krishna Bihari Pandey titled "Sati Savitri"

Sati Savitri is a well known puranic figure from Srimad DeviBhagwatham and Mahabharatha as one of those who fought with Yama to save her husband.

2/

This story is a modern real-life experience which mimics the puranic account in it's own unique way.

The story occurs in 1975 with Prof and his wife in Delhi with professor working as a researcher in university. Prof's family is in Allahabad in a large joint family

3/

Once Prof gets to know that his mother is not keeping well. He goes to his native and brings his mother. With dedicated care of his wife, his mother recovers quite remarkably and regains full stamina and strength

Mother-in-law & Daughter-in-law go out for shopping frequently

4/

Life's going smooth until one day when they receive a telegram that Prof's father is not keeping well.

His mother is distressed about the situation and requests her son to take her to the native. Prof is a little angry due to frequent travels and turns it down

5/
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Dr. Jane Clare Jones
Dr. Jane Clare Jones
@janeclarejones
So, on the subject of bonkers hyperbolic pretzeling over the Bell judgement, Grace 'destroy books I don't like & make inappropriate jokes about sterilising teenage girls' Lavery has some thoughts.

Tell me why my feminism is wrong Grace.

Oh

Well, if anyone thought the Bell judgment was going to make TRAs reconsider making massively overblown claims with no evidence backed up with nothing but a thick wadge of emotional blackmail.... HAHAHA, no one thought that.


A high court in the UK made a delimited judgment about teenager's ability to consent to puberty blockers. This puts all trans people everywhere in the world at risk.

Because if any human anywhere has any thoughts that deviate in any way from the rote line dictated by

the trans rights movement, this puts all trans people everywhere in mortal danger.

Let's be honest Grace. It doesn't put trans people at risk. It puts trans ideology at risk. Because trans ideology depends on the idea of innate gender identity, and the trans child is the

necessary material evidence of the ontology of gender identity.

That is, children are being medicalised to provide evidence to underwrite adults identities.

Nothing to see here.
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Pieter Levels \u2728
Pieter Levels ✨
@levelsio
Joe Rogan's podcast is now is listened to 1.5+ billion times per year at around $50-100M/year revenue.

Independent and 100% owned by Joe, no networks, no middle men and a 100M+ people audience.

👏

https://t.co/RywAiBxA3s

Joe is the #1 / #2 podcast (depends per week) of all podcasts

120 million plays per month source https://t.co/k7L1LfDdcM


https://t.co/aGcYnVDpMu
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Noah Smith
Noah Smith
@Noahpinion
1/OK, data mystery time.

This New York Times feature shows China with a Gini Index of less than 30, which would make it more equal than Canada, France, or the Netherlands. https://t.co/g3Sv6DZTDE

That's weird. Income inequality in China is legendary.

Let's check this number.

2/The New York Times cites the World Bank's recent report, "Fair Progress? Economic Mobility across Generations Around the World".

The report is available here:

3/The World Bank report has a graph in which it appears to show the same value for China's Gini - under 0.3.

The graph cites the World Development Indicators as its source for the income inequality data.


4/The World Development Indicators are available at the World Bank's website.

Here's the Gini index: https://t.co/MvylQzpX6A

It looks as if the latest estimate for China's Gini is 42.2.

That estimate is from 2012.

5/A Gini of 42.2 would put China in the same neighborhood as the U.S., whose Gini was estimated at 41 in 2013.

I can't find the <30 number anywhere. The only other estimate in the tables for China is from 2008, when it was estimated at 42.8.
SOCIETY