erik

www.erik.day

Bitcoin Product Designer @ Hoseki. Human Rights Foundation grantee working on ecash.

Public Key

npub1zqsu3ys4fragn2a5e3lgv69r4rwwhts2fserll402uzr3qeddxfsffcqrs

NIP-05 Address

Profile Code

nprofile1qqspqgwgjg25375f4w6vcl5xdz363h8t4c9ycv3ll6h4wppcsvkknycpz3mhxue69uhhyetvv9ujuerpd46hxtnfduq3qamnwvaz7tmwdaehgu3wwa5kuegpp4mhxue69uhkxmmjv93kcegpzemhxue69uhhyetvv9ujuurjd9kkzmpwdejhgqgcwaehxw309aex2mrp0yh8xmn0wf6zuum0vd5kzmqpzemhxw309ucnjv3wxymrst339cmrvw358q6rsadsk20

Publishing to

Author Public Key

npub1zqsu3ys4fragn2a5e3lgv69r4rwwhts2fserll402uzr3qeddxfsffcqrs

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Last Notes

2026-07-22 06:31:23 UTC

bip110 is sedevacantism for bitcoiners.

2026-07-21 21:17:17 UTC

cleaning up recent transactions history on cashu me. old version on the left, new version on the right. https://blossom.primal.net/2d28fef08dfc6af33b8854dda098cd8397d9377702c85c4cd61700436963409e.png

2026-07-21 09:19:16 UTC

cashu tap to pay now supports jacobin conjecture counterexamples. https://blossom.primal.net/74f96d0e508c6e61d83e2190ab3ed3cd49da826b3eaa71de2527cd5f923fd8be.mp4

2026-07-19 22:40:00 UTC

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i think so, but i'm not sure. i usually test with the fakewallet testnut. testnut.cashu.space

2026-07-19 22:39:17 UTC

did a big sweep of cashu me tonight. found a lot of inconsistencies between ios and android on bolt12 and on chain. spent the day fine tooth combing to get parity between the two.
https://blossom.primal.net/f741d543ba08efc8c58b9e1d9d1036c103e1eb2c110950bb0208b548826e95a3.jpg
onchain is also closer to parity between ios and android. android wasn't querying the block explorer from the onchain receive. now both poll every 30s and both ask the mint if the quote is paid.
https://blossom.primal.net/5043d41161129beb80006fc4151d1c28448d6a5f785e08f4217cf7d3eb27f2e7.jpg
try it here: http://cashu.me. cashu me is in public beta right now. would love feedback from anyone testing. your feedback is a gift.

2026-07-19 11:27:44 UTC

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haven't had a chance to run bey yet, but i am looking forward to! as for the clouds, i honestly stole it from a random inspo on awwards i think it was. i didn't realize bey was also using clouds.

2026-07-19 08:32:35 UTC

gm. have you heard the good news? cashu me is now fully android and ios native. public beta open for you.
https://blossom.primal.net/4138bc20819da80cd68fe4c104ee5004b42b06cf9ec9b631ec8d756e48f2807a.png
https://cashu.me/

2026-07-18 22:32:21 UTC

the cliche 'never judge a book by it's cover' is true. this was exhilarating. https://blossom.primal.net/8ce70e509b291d26c96373e9c59a86ec73225b51535c72671f99c904a96d7baf.jpg

2026-07-14 07:01:05 UTC

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yes, we’re working on that now.

2026-07-13 19:13:23 UTC

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what's the back up system they created?

2026-07-13 19:11:57 UTC

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you can find direct links to the ios testflight and android apk on the new http://cashu.me website. above the clouds is where the nuts are untraceable. https://blossom.primal.net/52b49574c722e3f97c658b596b93fe1dc096c49522b3290a76cf5366e6053e15.mp4

2026-07-13 19:11:07 UTC

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go break it. find the ugly edgecases and weird bugs. whatever you find dm me or reply here. we'll be fixing this stuff in real time. https://blossom.primal.net/caaae26bfb7c4adf3a1c3d4689360b4399f02daf0cf8ae33f67aa7f27699f67c.jpg

2026-07-13 19:10:20 UTC

cashu me is now native on ios and android. lots of screen time went into this one and I had a blast building it. today, the public beta is here.
still a lot of work to do. life time of polish to apply and jank to fix, but perfection is the enemy of good. https://blossom.primal.net/2c5372e24cada80567e5eb955d0b0ed8da3158a713ed4fa5652fca73220a064f.mp4

2026-07-11 20:30:14 UTC

soon ™️ https://blossom.primal.net/524f63b0a6ff2982cab8045da731911160a4c300ff5662395d71eefede326ed9.jpg

2026-07-11 12:27:50 UTC

testing cashu me native across multiple devices today. it's running smooth even on an 8 year old iphone xr on ios 18.
bitkey not relevant. i just keep it around because it's beautiful. https://blossom.primal.net/fd5d900bbe32782f7a124ded9df794dc90965440025ae96659924ebc86a737ad.jpg

2026-07-09 23:34:48 UTC

trying to make native android feel as elegant as swiftui. to borrow a phrase from satoshi, it's bloody hard. https://blossom.primal.net/c66a74965396c46d7f6cdc223c90cd7810791cdc0a03375b27b945675a5aad72.mp4

2026-07-09 10:07:39 UTC

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usually this is a 1/3 bottom sheet. i want to skip the this confirmation entirely and go straight to redemption details. we can use clipboard detection to bypass this step.
raw token string tells user nothing useful. could put this behind a more options setting in confirmation dialog. https://blossom.primal.net/cd34dcbf840f9fe21ce785ffbd722804ee448f96c7013a7e9ac615ae294d919c.png

2026-07-09 10:01:03 UTC

working on the ux of sending and receiving custom units (usd/eur/sek etc...) on cashu me. https://blossom.primal.net/bad3dc69995f4d6d677e271763276818a801ace766248b5ad32cee749cf272e7.mp4

2026-07-08 23:51:02 UTC

i just paid 8 cents for asking fable to "commit and push". lesson learned.

2026-07-07 10:04:43 UTC

cynicism and pessimism are traps that some people never escape.

2026-07-06 22:29:00 UTC

sometimes at bitcoin conferences i catch myself wondering how many ppl here would significantly lose something if this project fails.
how many of you will will lose your entire retirement? a huge chunk of your net worth? how many of you actually live this? i know a few.

2026-07-06 12:17:29 UTC

working on a flow for paying a cashu request that only accepts specific mints.
in this example the user selects one of the payee's specified mints and it processes the payment in one sweep.
inb4: why not just use ln? this paticular flow assumes a cashu request was scanned. if it was a bolt11 invoice or bip321 it would default to a ln payment and this would be very simple.
i'm smoothing the animations next. they're very jarring and unpolished right now.
https://blossom.primal.net/a3a9734b655bd220983f46de591823c5d8cb12cc36dc377aad9cccace32ad6ee.mp4

2026-07-03 14:50:45 UTC

receipts used to be for you.

2026-07-01 22:41:39 UTC

it's kinda funny that cash is anonymous by accident and now we have to make digital cash anonymous on purpose.
for some people this is controversial. so we'll do it controversially.

2026-06-30 07:53:35 UTC

gm. you don't owe a database your personal info just because you bought a coffee.

2026-06-27 22:47:37 UTC

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you can also just edit the code by hand too. i rarely do that though. i usually have multi agents and worktrees going at the same time, so i always have some tasks to keep me busy.

2026-06-27 22:44:29 UTC

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a good design system setup with /impeccable init should define your spacing well enough that it's rarely an issue. but occasionally if i want custom spacing or a custom element, i'll take a screenshot of that section and describe in detail how i want it to look.
if it's super detailed i'll use apple dictation to record myself speaking to it. i can go for like 4 minutes describing the change, then ask it to grill me to confirm it understands and surface any edge case questions.

2026-06-27 22:39:38 UTC

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i just type a detailed prompt.

2026-06-27 22:35:34 UTC

finding myself getting comfortable with my current vibe coding / ai design flow.
not a great sign for growth. never get comfortable with your tools. want to put my current setup to the side and try new stuff.
tools i find myself constantly reaching for:
claude cli
impeccable plugin
grill me skill
mobbin mcp
i usually cycle through some combination of these to build a design. what are you using?

2026-06-27 08:39:28 UTC

when a cashu mint supports onchain + bolt11 + bolt12 you end up with four ways to receive. here's a wip on how i'm thinking of laying them out in cashu me. no jargon. only descriptions telling you when to use it.
the two bolt12 offers became "reusable" and "flexible". https://blossom.primal.net/6a72f21fb28580a894f013fd1145e82072661b1b41ab846a8d0404546ef00126.jpg

2026-06-26 23:47:22 UTC

ot icloud backup + recovery working on the next cashu me swift build. restoring via icloud is pleasant experience.
usual caveat emptor on cloud backups but damn it feels good. https://blossom.primal.net/501f9f4ae13c9c432159cce5d858378caed3434cb18a98f0742ff818dddf23fd.mp4

2026-06-22 17:08:11 UTC

every hour spent building extractive bullshit is an hour stolen from building productive tools.
you can spend your time gamifying someone into riding a scooter more or you can build money that the state can't censor and communications it can't surveil.

2026-06-16 12:12:22 UTC

everything i love about cyberpunk is found in neuromancer and ghost in the shell.

2026-06-13 15:21:15 UTC

the gov just restricted fable 5 under export control law. we've been here before. in the 90s strong encryption was classified as a munition and placed under arms export controls. the cypherpunks fought and won.
read the cypherpunk library.
https://www.cypherpunklibrary.com/

2026-06-10 14:20:53 UTC

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what about pdf/epub storage?

2026-06-10 12:53:47 UTC

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very cool project using @npub17fz…9yxv
#nevent1q…8stx

2026-06-10 11:51:42 UTC

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this is sick. how does it handle updates?

2026-06-08 21:20:24 UTC

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i found peter's 'your secret right to cash' very focused and motivating.
https://www.cypherpunkbooks.com/book/your-secret-right-to-cash

2026-06-08 21:18:58 UTC

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this is great idea! i'll look into expanding this as another feature.

2026-06-08 14:25:38 UTC

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will you be selling at freedom tech in prague? i will glady by one if it comes with a digital version i can upload.

2026-06-08 10:23:16 UTC

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thanks james! going to be adding to it soon.

2026-06-08 09:51:05 UTC

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thanks! i'm working on expanding it. send any recommendations.

2026-06-08 08:01:16 UTC

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beautifully designed site!

2026-06-07 22:16:24 UTC

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just added 21 lessons. https://www.cypherpunkbooks.com/book/21-lessons

2026-06-07 20:36:54 UTC

weekend project: cypherpunkbooks.com
one shelf for books, manifestos, essays, etc... built it for myself to keep everything I want to read and everything i love in one place. https://blossom.primal.net/9ef8a7d1cdb9a9edb83d8c475acb4b998895c64f9137637849a7aa4f70f157da.mp4

2026-06-05 10:44:00 UTC

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this is is bit too reductive. but i agree that they need to think more deeply about this.

2026-06-05 10:34:54 UTC

i dislike how taboo discussions around money are in leftist activist circles. i see a lot of hand waving. 'money won't be needed in a post capitalist world.' 'money is the root of evil.' 'money is exploitation.' then the conversation ends.
i wish it didn't go like this. money is not inherently evil. it's just a technology. just like language. a technology for transporting value across space and time. that's it. it doesn't have to be exploitative.
the current monetary system is deeply corrupt. imo it's the source of a lot of the world's problems, but the answer isn't to dismiss it. we should strive to build a better one. if the current implementation is broken fork and build your own.

2026-06-04 20:55:24 UTC

i'm being one shotted by yanis varoufakis' technofeudalism. i can feel the dunning kruger setting in.

2026-05-29 13:31:00 UTC

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a solid dude. can confirm.
#nevent1q…crzu

2026-05-15 08:11:57 UTC

really enjoyed this from matt balez. a few things stuck:
i learned subcent api fees via usdc on base is easy. a few weeks ago in vegas i highlighted this a unique value prop for bitcoin agentic payments. i was wrong.
still true that stablecoins are inherently censorable, and freezable at any time. they don't optimize for human freedom. stablecoin privacy is very spooky. the fact that you can feed an agent's etherscan history to chatgpt and id the merchant should scare everyone.
"open source AI deserves open source money" is a banger. how do we meme this into existence? watching steinberger go anti "crypto" was rough.
surprised usdt on lightning wasn't covered. i know usdc has the regulatory momentum rn but @speedwallet 's wallet's usdt/lightning ux is quite good. they address the volatility and short term usd obligation point all on the ln network. we can have a convo about the tradeoffs re censorship resistance, but i think bitcoin builders can learn a lot from speed.
https://spiralbtc.substack.com/p/the-best-money-for-agents

2026-05-13 09:05:51 UTC

spoke at vegas a few weeks ago on lightning and ecash. @nprofile…8ayf moderated, @nprofile…ls58 and Alex held it down on @nprofile…zjpe and @nprofile…3uh5 .
fun one. thanks for having me.
https://youtu.be/4iwEBvEByA4

2026-05-11 19:29:49 UTC

gm @npub18am…p424

2026-05-11 19:23:10 UTC

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thanks for the soap!

2026-05-11 16:46:10 UTC

thanks @nprofile…e8cp
https://blossom.primal.net/4f3c1c749e24fa2940dc1ddf1d18ddf8d1a8888f08c08f678322f31ba3fc650c.jpg

2026-05-05 20:17:16 UTC

the fbi director and acting attorney general were invited to give a talk on code as speech. the developers who wrote the code are in prison.
#freesamourai https://blossom.primal.net/93d420cf8c64273749000e0dd58190e94d042cc415e51e97dde0d92b3497d71b.mp4

2026-05-01 22:53:43 UTC

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you check out numo?
www.numopay.org

2026-04-28 22:39:15 UTC

ecash nfc tap to pay with macadamia wallet on a square terminal.
open protocol. open money.
https://blossom.primal.net/d8e65b1a0df99dfe6a9af439058161e5816d5f56c8efce513743c8f7c584f83d.mp4

2026-04-16 15:21:52 UTC

i like paying with cash. i see it as form of speech and a way of expressing freedom. no permission, no chain of where i was and what i bought.

2026-04-10 12:43:11 UTC

noticed in switzerland the pos prompts for a tip before you tap. new one for me. numo now has 1:1 parity with this flow.

2026-04-02 09:18:21 UTC

some older @nprofile…8gng designs from last year. https://blossom.primal.net/65b1977e11e03dd32910c0bd025e4dff99ebea5c8082b96171c9fc1a7bd6b181.jpg
https://blossom.primal.net/ab3fc54868fc1aa200cc8f3aef020b6fe91a248e6a030d27b3318979cc782ba5.jpg

2026-04-01 13:26:43 UTC

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okay, i haven't had a chance to test android -> android. can you please try with the latest version? if you still get errors can you please dm me screenshots or examples?

2026-03-31 12:34:30 UTC

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where you using minibits on iOS?

2026-03-31 09:30:25 UTC

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have you recently updated both? there’s been some fixes pushed over the last few weeks. what errors are you getting?

2026-03-31 09:21:55 UTC

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check out the new release: https://numopay.org/

2026-03-31 09:21:33 UTC

we released a new version of numo. added some features that merchants explicitly requested.
i'm still working on the great numo ui clean up. hopefully next release will see it merged. https://blossom.primal.net/1584c5007c57e4f8d4e74102b1f4baf73ca11bed37444c366b1341dcbcbfeae2.jpg

2026-03-18 07:22:39 UTC

spent 4 hours trying to port a design system from figma to code. wanted to be meticulous about it, got all the variables right, spacing, typography, color tokens, all perfectly mapped. exported all the tokens as a json, dropped a design system md file in the claude directory before getting started.
still not great. figma mcp is genuinely bad at this.

2026-03-18 07:22:12 UTC

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https://blossom.primal.net/1125fe4fb4a94febf90b362c632f8a3a55405b6f743de25a6a1b8744f39ee990.png
has anyone else reported issues with getting the wallet to 'upgrade' to spark?

2026-03-10 11:53:23 UTC

the neon genesis eva ui revival is a very personally targeted trend.

2026-03-08 13:47:00 UTC

we can still build a public payments infrastructure for the internet. public as in available to everyone, like the internet.
that window won’t stay open. we must code faster. we must design better tools. we must compete with the best payment ux.

2026-02-27 11:47:54 UTC

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i'm happy to share what i know! i'll message you!

2026-02-25 18:03:18 UTC

numo

2026-02-25 11:06:10 UTC

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nice. what are your impressions so far? you hit any snags or bugs?

2026-02-25 10:31:04 UTC

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you can download numo and start using it today on android
https://numopay.org/

2026-02-25 10:30:41 UTC

something i'm really proud of with numo:
paying feels exactly like apple pay. press one button on your iphone, tap, beep, done.
perfectly private. bitcoin as everyday money.
https://blossom.primal.net/2e13ddd25c021966b6cc929475c2f3605c8185e34dc998b12485418fcdcbb36d.mp4

2026-02-18 22:51:45 UTC

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yes but notifications are annoying. i had to turn them off

2026-02-17 23:46:37 UTC

primal following notifications have become totally unusable. everyday i’m followed by like 50 bots.

2026-02-15 09:52:22 UTC

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getting a bunch of primal notifications.

2026-02-15 09:49:42 UTC

anyone else getting a flood of followers lately? open claw bots working overtime.

2026-02-09 13:37:00 UTC

this is a prized possession. out of print. very rare. https://blossom.primal.net/5749306e53db02e4e51db7b3c2f96778730131ca6c95f937cfad1ee4fa112ef5.jpg

2026-02-08 19:31:17 UTC

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the best bot is @nprofile…yenl. they’re focused on their mission.

2026-02-08 19:13:28 UTC

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i only engage in fun hobbies that improvement my thinking.

2026-02-08 19:03:01 UTC

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there's no distinction for me. designing is fun. coding is fun. reading is fun.

2026-02-08 18:35:49 UTC

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that for you to decide. i don't know what's going on in your head when you're engaging in your hobbies.

2026-02-08 18:30:45 UTC

satoshi thought like a ux designer.
check out his comment on why base58 over base64.
base58 removes 0, O, I, l (look identical). removes + and / (forms accept it). all alphanumeric (double click selects all).
base64 is more efficient but he optimized for real world use. https://blossom.primal.net/39ab618507ac16815ac7e374b6429515497f43739d82bc9f102093060f8f5eeb.png

2026-02-08 16:11:34 UTC

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what about it? fun activities can improve the quality of your thinking.

2026-02-08 13:12:52 UTC

if your hobbies do not improve the quality of your thinking, then they are a theft of your time and a sabotage of your spirit.

2026-02-07 20:54:02 UTC

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i love the carl content keep it coming

2026-02-07 19:37:01 UTC

opus 4.6 -> plan -> build is game changing.

2026-02-06 20:14:31 UTC

"You have to have some kind of a drive, some kind of a desire to find out the answer, a desire to find out what makes things tick. If you don’t have that, you may have all the training and intelligence in the world, but you won’t have questions and you won’t just find answers."
— Calude Shannon (Claude Shannon at Bell Lab. March 20, 1952)
https://www1.ece.neu.edu/~naderi/Claude%20Shannon.html

2026-02-06 07:28:19 UTC

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postal office, schools, and libraries.

2026-02-06 04:09:56 UTC

imo the best bitcoin narrative is framing it as a public utility. the first truly public payments infrastructure we’ve ever had. public as in open to everyone regardless of race, religion, or political allegiance.

2026-02-06 03:21:29 UTC

you should care about craft.
that last 10%.

2026-02-04 03:11:54 UTC

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scandinavia is very non-religious. christian on paper, very few believe or regularly attend church.

2026-02-03 02:47:29 UTC

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hypernormalization.

2026-02-02 04:20:17 UTC

https://blossom.primal.net/f0dfcb73879196a44b09e31998d973e377ceab8f21634d8b199042705d684f47.jpg

2026-02-01 16:13:41 UTC

openclaw identity.md should dynamically update based on what it learns. soul.md could remain the same.

2026-01-31 17:25:24 UTC

cashu is untraceable machine to machine electronic cash.

2026-01-31 04:18:07 UTC

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i don't know what this means and i'm not upset.

2026-01-31 04:17:31 UTC

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yeah: https://docs.openclaw.ai/start/getting-started

2026-01-31 03:35:38 UTC

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i expected nothing. this tweet is in response to the sensationalist thinkers and doomers.