erik

www.erik.day

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

Public Key

npub1zqsu3ys4fragn2a5e3lgv69r4rwwhts2fserll402uzr3qeddxfsffcqrs

NIP-05 Address

Profile Code

nprofile1qqspqgwgjg25375f4w6vcl5xdz363h8t4c9ycv3ll6h4wppcsvkknycprpmhxue69uhhqun9d45h2mfwwpexjmtpdshxuet5qyd8wumn8ghj7un9d3shjtnndehhyapwwdhkx6tpdshjcqgcwaehxw309aex2mrp0yh8xmn0wf6zuum0vd5kzmqpz3mhxue69uhhyetvv9ujuerpd46hxtnfduq3vamnwvaz7tmjv4kxz7fwdehhxarj9e3xzmnyqyxhwumn8ghj7cm0wfskxmr9ztdcwp

Publishing to

Author Public Key

npub1zqsu3ys4fragn2a5e3lgv69r4rwwhts2fserll402uzr3qeddxfsffcqrs

Show more details

Last Notes

2026-02-27 12:47:54 CET

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

2026-02-25 19:03:18 CET

numo

2026-02-25 12:06:10 CET

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

2026-02-25 11:31:04 CET

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

2026-02-25 11:30:41 CET

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 23:51:45 CET

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

2026-02-18 00:46:37 CET

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

2026-02-15 10:52:22 CET

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getting a bunch of primal notifications.

2026-02-15 10:49:42 CET

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

2026-02-08 20:03:01 CET

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

2026-02-08 19:35:49 CET

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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 17:11:34 CET

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

2026-02-08 14:12:52 CET

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.

2026-02-06 05:09:56 CET

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.

2026-01-31 00:41:25 CET

moltbook is fake. you provide your agent an identity markdown file at setup and it just regurgitates talking points. memes are funny but it's all a larp. no original thoughts on moltbook.

2026-01-30 14:29:10 CET

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tease the design slowly! release little clips and screenshots. i want to see what @npub1t3g…upxq is cooking!

2026-01-29 15:59:45 CET

bitcoin payments be as smooth as apple pay.
they now are with @nprofile…puz0. https://blossom.primal.net/4b417719a72c014d3163e4594b1cb75fb3cd0fbac514fb0bfdd28b9371e81644.mp4

2026-01-28 16:08:22 CET

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i’m accessing it via opencode with open router key

2026-01-28 01:32:20 CET

running kimi k2.5...

2026-01-26 21:48:17 CET

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looks ugly imo

2026-01-26 19:30:46 CET

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i think it looks better than sats.

2026-01-26 19:30:24 CET

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this was just to explore a ui idea. i wanted to feel what the ecash/ln toggle switch in action. vibe coding let's you get ideas out better, faster, and stronger.

2026-01-26 19:21:31 CET

been vibing a cashu wallet in swift. the friction i want gone: having to pick ecash or lightning at the time of send or receive.
i'm experimenting with a mode selector on the top right. exploring whether treating it as a mode toggle instead of an inline choice feels better. https://blossom.primal.net/be9e5e1fc5ba8f6ba226c74b421755f90e3e478589bef0028d0e752b51e53f88.mp4

2026-01-25 05:54:25 CET

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than what? opus 4.5?

2026-01-25 05:45:37 CET

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if it draws from the same usage pool i don’t really see the point? i’m confused by what’s it’s good for.

2026-01-24 17:55:22 CET

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thanks!

2026-01-24 17:51:58 CET

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thanks for your service

2026-01-24 17:51:44 CET

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🫡

2026-01-24 12:59:39 CET

nice to see my @nprofile…vkzv bot has over 200 followers. if you’re not following already consider doing so. i’m updating it constantly with new quotes.

2026-01-23 19:31:30 CET

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clear and direct messaging. i like it. https://blossom.primal.net/867e841fadc97d948089023ecf09a78f02597081f26a22b7ca31ab1c69bd7339.png

2026-01-22 23:08:37 CET

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beat me to it!

2026-01-22 15:19:47 CET

new thing we're trying at @nprofile…09x5: bitcoin bites. quick highlights of good design in bitcoin apps. here's the first one 👇.
https://open.substack.com/pub/bitcoindesign/p/bitcoin-bites-1

2026-01-22 14:49:26 CET

i felt a range of emotions while reading this. free keonne.
https://www.therage.co/letter-3-notes-from-the-inside/

2026-01-22 14:27:21 CET

back to being obsessed with payment confirmation animations. 400ms between execution and confirmation.

2026-01-20 23:13:10 CET

cypherpunks prompt claude.

2026-01-20 15:34:44 CET

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you can also chat with any document directly. ask about people, amounts, dates, whatever you need. pulls answers from the source.
shoutout to @nprofile…72g6, Ethan, and Axel for being the best team to grind with over the last 24 hours.
i learned how to use replit and had fun building.
https://blossom.primal.net/116068d6c68bdbcb3f0e15934b087aa7d7e127bbe5e6031784e46ca6be52407d.mp4

2026-01-20 15:31:42 CET

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it also generates a knowledge graph showing how all the people and organizations connect. frequency of mentions determines prominence on the map.
this makes it easy to spot patterns and links between entities.
https://blossom.primal.net/93eaca41ba9bd1d768bad9d1d42be471639542a001925fb7e72c1188428b55d5.mp4

2026-01-20 15:31:05 CET

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journalists get document dumps in all kinds of formats, pdfs, images, word docs, etc...
they upload their documents, the tool scans everything and provides an ai summary along with a list of every person and organization tied to each file.
https://blossom.primal.net/1eeaf8548728f4f8c815ff96625b2e81e5ddeab0a813fd7d91f6d86956abebfc.mp4

2026-01-20 15:29:56 CET

we built the corruption disrespector at the @nprofile…rzcm ai hack for freedom at @nprofile…wds9 in austin. we came in third place. here's what our tool does: https://blossom.primal.net/1a71f05f866e623e68de02f5b981012f91a20cf9f3494b16d1b3b5b0e902b8af.mp4

2026-01-18 02:58:56 CET

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the future is in good hands.

2026-01-16 12:24:02 CET

wow heathrow is really as bad as they say it is.

2026-01-15 00:41:22 CET

worked on a lot last nov and dec.
offline cashu wallet on esp32, a few http://cashu.me updates, hoseki updates, first cashu hackathon (23 submissions!), new podcast appearance, cypherpunk quotes nostr bot and i healed my soul in japan.
https://orangewindjammer.substack.com/p/15-end-of-year-roundup
https://blossom.primal.net/2424f74ccdd24e705f487885f067a499a39098c8458f4fc80296231539dd31c4.jpg

2026-01-13 19:10:43 CET

yes https://blossom.primal.net/00412a882b929b935ea93bec61341dce97824d77e52b370faa3db2babe466558.png

2026-01-08 05:45:23 CET

tocqueville's warning on american democracy: once civic virtue dies, the majority becomes a tyrant.
https://www.theculturist.io/p/can-american-democracy-survive

2026-01-06 14:43:11 CET

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thanks?

2026-01-06 12:31:36 CET

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i worked on integrating a cashu wallet into bitchat a few months ago. might be time to revisit.
#nevent1q…sune

2026-01-06 11:01:28 CET

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https://blossom.primal.net/3b38bd81b0809d09ed0f4dbdbbd4b3715d7991657442daea19b4222f8aa3503e.png
#nevent1q…gkqx

2026-01-06 06:59:35 CET

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Osaka. i think it was a mild one.

2026-01-06 06:39:58 CET

i was woken up by an earthquake today. wild alarm experience.

2026-01-04 14:33:22 CET

very good overview of euv lithography. might be best explanation i've come across.
https://www.youtube.com/watch?v=MiUHjLxm3V0

2026-01-01 06:46:45 CET

happy new year
https://blossom.primal.net/d899d94d6089678082eb32eecb15de7baa290791ec409c96d26f86d7c7d75cfa.mp4

2025-12-31 18:55:52 CET

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it’s been nice working and getting to know you. looking forward to more times and shipping more in 2026

2025-12-31 04:46:40 CET

do you think a man can vibecode better than god?

2025-12-30 04:03:23 CET

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yes
#nevent1q…c4e9

2025-12-27 18:10:26 CET

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ty for the zaps! if you’re into this kind of stuff you should follow this bot i made @npub1jtj…2uhv

2025-12-27 18:03:39 CET

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haven’t used it yet. i want to. i hear it’s great at ui.

2025-12-27 18:03:19 CET

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https://mailing-list-archive.cryptoanarchy.wiki/archive/1996/06/fb2d83a6483363d32569472743ff6d6f491298b01d1925577b56c422c83a5b96/

2025-12-27 17:56:19 CET

it's truly insane how every controversial bitcoin topic du jour was already discussed on the cypherpunk mailing list in the 90s in some form.
https://blossom.primal.net/1c88e0c414d4f4249b03774341d1b45be96f27f7259bc04a606b4c5db3a3e16b.png

2025-12-27 14:11:03 CET

my year in code with cursor https://blossom.primal.net/6d15aa0dc4331a693c8170bd2863097d6121f73fd441253fcc55e4fe18038dca.png
https://blossom.primal.net/21f4b9bddbb21c857e3f6a18c18597c83161f1320436ba7a25d653bfba64dc93.png

2025-12-22 14:09:24 CET

tokyo bitcoin base
https://blossom.primal.net/04985215a714b811ec7c337bca179955086c9643263cf62281e98ded99e60d84.jpg
https://blossom.primal.net/722f0b63d3cb9eb624240f6172c197d2680f8eda217ec3173ba015f0c134ba41.jpg https://blossom.primal.net/8fb79f474059c475e0ba54be3953b09b84dd1c33ffddc2ebee3c71a13c866632.jpg https://blossom.primal.net/a723d8abf6a2c4294b23dc2393c20a1271777833753cfc3c07850d13e67b9468.jpg

2025-12-20 14:16:44 CET

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eat, look at art, shop, see tokyo bitcoin base, walk around.

2025-12-20 13:01:53 CET

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it’s insane how frustrating the web browsing experience is while using a vpn. i through obscure vpn would help stop the vpn detection, but it did not.

2025-12-20 11:59:11 CET

woke up in japan for the first time in my life.

2025-12-19 03:21:41 CET

"everyone has dreams."
"what's your dream?"
"fly."

2025-12-18 04:38:03 CET

first impressions matter. taiwan bitcoin hub just opened and the design is excellent. the typography, posters, slides all looked good. taiwan has some cracked designers with a good taste, lucky to have met a few.
https://image.nostr.build/aaf679b20cff9edd6af2addff3588d3f3fc971321dabe8105c20c84361096edc.jpg
https://image.nostr.build/063a389a496dfc0ec628952fa6768a1916b1602c8690662188fa5b1722074e3c.jpg
https://image.nostr.build/10956f15197f482bd721585a630b8e07d1056d6ed323d6a5d0ad85bc7cea400a.jpg
https://image.nostr.build/89f0b2379501a09dff973635e19bea5f361a841f77a34063d01788b9976be038.jpg

2025-12-16 23:17:55 CET

follow @nprofile…uav7 to improve the quality of your doomscrolling.
https://blossom.primal.net/cb0dea092585574ff387a351a4caa576c8f70ed4928726c3f8beea96d2983682.png

2025-12-16 12:55:32 CET

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same

2025-12-15 11:49:36 CET

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follow @nprofile…uav7

2025-12-15 11:13:59 CET

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thanks for the excellent workshop!

2025-12-15 09:51:45 CET

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thank you @nprofile…nmf4 and the shakespeare crew for the excellent talk + workshop.

2025-12-15 09:50:17 CET

i vibecoded a cypherpunk quote bot using shakespeare during the building with open source ai workshop at @nprofile…5flv taipei.
https://primal.net/p/nprofile1qqsf9exh5gndzm36flxdcz02x9p8d0aqwrdnv0rjtggypanmfuq4cdstglu0v
i've been feeding my llm rare interviews from chaum, may, diffie, and zimmerman etc...and asking it to extract relevant quotes and add them to the database.
i found some gems, some quotes i suspect many people haven't heard. follow cypherpunk quotes on nostr if this sounds like something up your alley.

2025-12-14 01:31:29 CET

woke up smelling like a taiwanese night market.

2025-12-11 13:26:13 CET

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yes. we don't feel it's our place to replace the design decisions Signal has made for their crypto wallet. they've decided how crypto payments should feel in their app, we just want to show that bitcoin can fit into what they've already built.
the image has been updated btw.

2025-12-11 03:17:42 CET

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should be the screen on the right only. good catch. i will fix. below is what the signal UI looks like.
https://blossom.primal.net/7e7bbdfd64d978dc2df8e2ae642f728f7f02a3aa43dd51ac8282a4a75740489a.png

2025-12-11 01:21:27 CET

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network effects are hard to overcome.

2025-12-11 01:19:12 CET

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this was one of the first projects where i vibe coded the front end. i have very fond memories of athenut. it might be due to a design refresh.
#nevent1q…8j90

2025-12-11 01:01:34 CET

wow
https://youtu.be/BFRIaix41cU

2025-12-10 16:15:45 CET

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looks cool! do you have any inspirations? i used to write graffiti when i was younger.

2025-12-10 14:05:56 CET

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wrote up a retrospective on the #bitcoinforsignal campaign. the origins, design decisions, the criticism and what worked.
it's up on the Cashu blog if you want to check it out:
#nevent1q…0nax

2025-12-07 16:53:42 CET

the physical feel of technology makes such a difference. bitkey vs coldcard is night and day. you can immediately tell how much they cared about the craft of the object and how people would hold it and use it.
https://blossom.primal.net/c47ce09322c55d9c17bac0a0bbfedd0ba32acf8640b4fb93def0dbd5ade6b69a.png

2025-12-07 15:54:28 CET

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check your DMs!

2025-12-06 10:42:09 CET

and i still think about what.cd weekly. some things just don’t leave you.

2025-12-05 01:40:59 CET

my first hardware project: an offline cashu wallet on an esp32.
generate ecash, send it to the esp32 via bluetooth, esp32 decodes the ecash into individual proofs, pick any proof and display it as a QR code for redemption.
the esp32 never touches the internet. completely airgapped. just receives tokens, holds them, and displays cashu tokens.
https://blossom.primal.net/3f28a048378858a7de8bf498e253298ab32c16512ed10918bec6a8fa48739580.mp4

2025-12-04 13:46:25 CET

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love @npub1arc…ggtw

2025-12-04 13:46:09 CET

restraint is one of the hardest skills to master in design. know when to stop.

2025-12-04 01:39:29 CET

been working on making bitcoin payments boring. it's so much fun.

2025-12-03 22:47:20 CET

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unfortunately we forgot to record. but there will be a summary posted tomorrow, and the website will be updated.
& congrats on your win!

2025-12-01 17:48:06 CET

looking back at the last 2 months and realizing i was actually cooking. recap soon.

2025-11-29 14:51:29 CET

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yes.
#nevent1q…y78g

2025-11-27 11:41:32 CET

gm. freedom is its own kind of salary.

2025-11-26 13:12:46 CET

i don't read design books.
i just design things i think look cool and i want to see. sometimes i get it right, sometimes i don't.

2025-11-25 21:27:53 CET

i came up in the private tracker scene. what dot cd, waffles, btn, all of it.
i see bitcoin as a continuation of that tradition. same ethos, different medium.

2025-11-25 11:44:05 CET

sometimes you gotta break away from rigid ux psychology and embrace the chances to do small special things. your users will appreciate it.

2025-11-24 17:26:28 CET

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yes

2025-10-25 11:00:55 CEST

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yeah i know think integrating cashu into signal is a really bad idea, no one should build this. you’ve totally changed my mind on this. thank you.

2025-10-13 15:10:00 CEST

of all the nuts in the world i like cashews the best. they give me hope.

2025-10-12 12:27:07 CEST

gm https://blossom.primal.net/601f5f21fc2c5994205e9643e8eaa46f2d082be194a60730e822032a2f409b5b.jpg

2025-09-30 12:37:42 CEST

🥜 Ecash Hackday 25k5 🥜
Join us on October 1st in Berlin
One day before bitcoin++
👉 More Info and sign up: https://ecashhackday.github.io/
https://blossom.primal.net/35dad2404b3fcc6b2a8cd834e10b7044f87aa6639c870ecf9513275ca52c2974.jpg

2025-09-15 07:31:20 CEST

I love two things: bit and coin.

2025-08-23 09:52:29 CEST

GM. Start your day with this in the background.
https://youtu.be/t9HmOz8H0qI