Commit `b021de29f4`

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cmc <hello@cleberg.net> · 2025-08-20 03:39 UTC

summary of commits from minimal-enhancements

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content/about/index.org added +27

		@@ -0,0 +1,27 @@
	1	#+title: About
	2	#+slug: index
	3
	4	Hey, I'm /~cmc/.
	5
	6	I'm a technology audit manager, working on financial statement audits (SOX/MAR),
	7	SOC 1-3 reports, and other attestations for KPMG.
	8
	9	Read up on my [[https://cv.cleberg.net][CV]] or [[https://cleberg.net/salary/][salary]] for more information.
	10
	11	In my spare time, I like to:
	12
	13	- Run linux servers
	14	- Enhance my home lab network
	15	- Write personal programs, mostly in Python
	16	- Research various topics (history, geography, science, etc.)
	17	- Write blog posts and general documentation
	18	- Converse with others on IRC and Matrix
	19	- Play video games and watch television
	20
	21	If you want to chat, you can find me in the following spaces:
	22
	23	- [[mailto:hello@cleberg.net][hello@cleberg.net]] ([[https://cleberg.net/gpg.txt][GPG]])
	24	- [[https://lemmy.cleberg.net/u/cmc][@cmc]] on Lemmy
	25	- [[https://matrix.to/#/@cmc.:matrix.org][@cmc.:matrix.org]] on Matrix
	26	- @cmc.01 on [[https://signal.org/][Signal]]
	27	- [[https://sr.ht/~cxc][~cxc]] on Sourcehut

content/blog/2025-06-02-private-ios-apps.org +111 −127

		@@ -4,16 +4,14 @@
4	4	#+slug: private-ios-apps
5	5	#+filetags: :ios:privacy:security:
6	6
7		In a world where our phones are extensions of ourselves, balancing convenience
8		with privacy can feel like a losing battle — especially on iOS, where platform
9		restrictions narrow the options. But it's not impossible. There's a growing
10		ecosystem of privacy-respecting apps, tools, and communities focused on helping
11		iPhone users take back some control.
	7	The world is evolving into a privacy nightmare, where our own devices are being
	8	used by numerous parties to constantly track and report on our activities. This
	9	is especially prevalent on iOS, where platform restrictions leave users without
	10	many options to lock down their data.
12	11
13		Below is a curated list of privacy resources, directories, and testing tools
14		specifically useful for iOS. Whether you're looking for a better email client, a
15		trustworthy VPN, or simply places to learn more, these links are a solid
16		starting point.
	12	However, there are apps that exist that can help enhance the privacy of an iOS
	13	device. The post below details a number of privacy resources, directories, and
	14	tools for iOS.
17	15
18	16	Resource Table
19	17
		@@ -36,38 +34,28 @@ starting point.
36	34
37	35	#+begin_quote
38	36	Note: This list focuses solely on iOS-compatible resources and tools. No
39		Android comparisons here — just options for those of us living in Apple's walled
40		garden.
	37	Android comparisons here as I have not used Android in many years.
41	38	#+end_quote
42	39
43	40	* Email
44	41
45		First and foremost, I like to consider email as my first app on a new device.
46		However, the iOS market lacks a wealth of open-source and private email clients.
47		There are a few options, such as Proton Mail and Tuta, which are open source and
48		private, but they lock you into their ecosystem. Tuta doesn't allow for custom
49		domains and neither allows SMTP/IMAP access.
50
51		Canary Mail is a decent option, as it is a classic SMTP/IMAP client - and does
52		more than most as it's one of the only PGP email clients on iOS - but is closed
53		source and the company behind it seems more focused on AI than privacy.
54
55		- [[https://proton.me/mail][Proton Mail]] - A more mainstream-feeling app with PGP support built-in. Good if
56		you're looking for something that feels like Apple Mail but with privacy
57		upgrades.
58		- [[https://tuta.com/][Tuta]] - Tuta (formerly Tutanota) takes privacy a step further by encrypting
59		subject lines, message content, attachments, and calendar events. It also
60		avoids using phone numbers or third-party services for registration. The iOS
61		app is reliable for the basics. Downsides: no IMAP/SMTP support, so you can't
62		plug it into your own mail clients, and notifications require a premium plan
63		if you want them in real-time. Great if you care about metadata exposure.
64		- [[https://canarymail.io/][Canary Mail]] - A more polished, user-friendly email client that supports
65		end-to-end encryption using PGP and their own “SecureSend” feature for
66		encrypted messages. Canary works with multiple mail providers (Gmail, Outlook,
67		etc.), so it's more of a privacy enhancement for existing services rather than
68		a private mail provider itself. Downsides: it's a proprietary, closed-source
69		app, and some privacy features require a subscription. Better than stock Mail
70		for security, but you're still trusting their implementation.
	42	First, I like to consider email as my first app on a new device. However, iOS is
	43	\extremely\ lacking in this area. Certain options are private, such as Proton
	44	Mail and Tuta, but they have certain restrictions and ecosystem lock-in methods
	45	that I try to avoid.
	46
	47	Canary Mail was a decent option for a while, although a bit mysterious, but they
	48	have recently leaned into the AI hype pretty heavily, which is concerning.
	49	However, it's still one of the only options for PGP emails on iOS.
	50
	51	- [[https://proton.me/mail][Proton Mail]] - One of the more popular private email options available on iOS.
	52	Allows custom domains, but does not allow for IMAP/SMTP usage, so you're
	53	locked into using their apps. Open source.
	54	- [[https://tuta.com/][Tuta]] - Tuta also locks you into their clients and they do not allow you to use
	55	custom domains. Open source.
	56	- [[https://canarymail.io/][Canary Mail]] - Closed source, so you can't verify anything about what they are
	57	building into the app. However, it's one of the only options for PGP mail on
	58	iOS. Advanced features are locked behind a paywall.
71	59
72	60	Another suggestion is to use a browser-based web client. You can install browser
73	61	mail clients as progressive web apps (PWAs). For example, I have been using
		@@ -91,35 +79,29 @@ releases for iOS, I will probably use that.
91	79
92	80	* Browsers
93	81
94		Your browser is basically the front door to the internet — and also the window,
95		mailbox, and security camera. It's where trackers, ads, fingerprinting scripts,
96		and data leaks happen most often. Even on a locked-down phone, if your browser
97		isn't protecting your traffic, your personal info can quietly leak out through
98		third-party scripts, embedded media, and background connections. Choosing a
99		privacy-respecting browser is one of the most impactful decisions you can make
100		for mobile privacy.
101
102		- [[https://apps.apple.com/us/app/firefox-focus-privacy-browser/id1055677337][Firefox Focus]] - A stripped-down, no-nonsense browser from Mozilla. It
103		automatically blocks trackers, erases your browsing history with a tap, and
104		skips extras like tabs or bookmarks. Great for one-off searches and quick
105		visits to privacy-sensitive sites.
106		- [[https://duckduckgo.com/app][DuckDuckGo]] - A full-featured private browser with built-in tracker blocking,
107		HTTPS upgrades, and a clear data button. It also integrates DuckDuckGo search
108		and email protection. Solid for daily use if you don't want your browsing
109		activity tied to a bigger tech company.
110		- [[https://onionbrowser.com/][Onion Browser]] & [[https://orbot.app/][Orbot]] - Your best bet for anonymous browsing on iOS. Onion
111		Browser routes traffic over Tor, while Orbot can proxy other apps system-wide
112		through Tor. Slower than normal browsers, but excellent for masking your IP
113		and avoiding surveillance.
114		- [[https://brave.com/][Brave]] - Privacy-focused with ad and tracker blocking built-in, Brave also runs
115		its own private search engine and supports things like Tor tabs (on desktop,
116		not iOS). On iOS, it's basically a privacy-enhanced Safari/WebKit shell —
117		better than nothing, but subject to Apple's browser engine limits.
118		- [[https://www.apple.com/safari/][Safari]] (with caveats) - Surprisingly decent for privacy if you tweak the
119		settings. Enable “Prevent Cross-Site Tracking,” block all cookies, and disable
120		preload for best results. Still, it's tied to your Apple ID and iCloud syncing
121		unless you're careful, so don't treat it as anonymous. For a great baseline
122		configuration, read PrivacyGuide's [[https://www.privacyguides.org/en/mobile-browsers/#safari-ios][Safari]] section.
	82	Your choise of browser is very important if you're concerned with privacy. Any
	83	and all links you click will be opened in your default browser, so you need to
	84	make sure you choose the right browser and configure it properly. Trackers, ads,
	85	fingerprints, and data leaks are constant threats that should be avoided when
	86	possible.
	87
	88	- [[https://apps.apple.com/us/app/firefox-focus-privacy-browser/id1055677337][Firefox Focus]] - In my opinion, the best option for privacy on iOS.
	89	Automatically blocks trackers, erases data and history upon app close, and
	90	focused on private usage. However, it won't support your bookmarks or keep you
	91	logged into sites long-term.
	92	- [[https://duckduckgo.com/app][DuckDuckGo]] - Another good option, built on chromium. Like Focus, it allows you
	93	to clear all data with a button tap.
	94	- [[https://onionbrowser.com/][Onion Browser]] & [[https://orbot.app/][Orbot]] - Tor - what can I say? It's been the most popular
	95	privacy browser for ages for a reason and now it's available on iOS. Onion
	96	Browser is a Tor browser and Orbot can proxy any number of iOS apps through
	97	Tor. As with all Tor traffic, it will be slower than "regular" traffic.
	98	- [[https://brave.com/][Brave]] - Another chromium-based privacy browser. Can sync with other Brave
	99	browsers via a secure linking process (no account). Fully-featured and great
	100	privacy defaults. There have been some concerns in the past about the company
	101	behind Brave, but I still think it's a decent option for most peoplel.
	102	- [[https://www.apple.com/safari/][Safari]] (with caveats) - Great option if the browsers above don't work for you.
	103	Be sure to read PrivacyGuide's [[https://www.privacyguides.org/en/mobile-browsers/#safari-ios][Safari]] section for more information on what you
	104	need to do to lock it down before relying on it full time.
123	105
124	106	#+begin_quote
125	107	I use: Hardened safari in private mode for every day use, and Onion Browser
		@@ -128,30 +110,26 @@ for anonymous browsing.
128	110
129	111	* Messaging
130	112
131		If you're trying to keep conversations off surveillance infrastructure, choosing
132		the right messaging app is crucial. Between metadata collection, insecure cloud
133		backups, and shady server practices, most mainstream chat apps aren't
134		privacy-friendly by design. On iOS, you're a little more limited than on
135		Android, but there are still solid options built around end-to-end encryption
136		and metadata minimization.
137
138		- [[https://signal.org/][Signal]] - The gold standard for secure messaging. Open source, end-to-end
139		encrypted, and runs its own private push notification infrastructure so Apple
140		can't read your message content. Downsides: phone number required for signup
141		(a known metadata weak point).
	113	Next up are messaging apps. If you have an iPhone, it's a good bet that you will
	114	be messaging other people on it. The threats for messaging apps tend to be
	115	metadata/data collection from cellular providers, ISPs, and Apple itself. If you
	116	want to protect the privacy of your messages, who your messaging, and the
	117	metadata around those messages (time, method, location, etc.), you'll need to
	118	think about which apps you're using.
	119
	120	- [[https://signal.org/][Signal]] - My personal favorite and still the gold standard for secure and
	121	private messaging. Open source, end-to-end encrypted, and runs its own private
	122	push notification infrastructure so Apple can't read your message content. A
	123	phone number is required to sign up, but you can create a username immediately
	124	after signing up and share that with others instead of sharing your phone
	125	number.
142	126	- [[https://simplex.chat/][SimpleX]] - A decentralized, phone-number-free messaging system. Uses anonymous
143		message relays and asymmetric keys. Great for pseudonymous chats or if you're
144		tired of number-based identity systems.
	127	message relays and asymmetric keys.
145	128	- [[https://getsession.org/][Session]] - A fork of Signal's protocol that eliminates phone numbers entirely.
146		Routes messages through a decentralized onion network (like Tor). Excellent
147		for metadata resistance, though message delivery can sometimes lag.
	129	Routes messages through a decentralized onion network (like Tor).
148	130	- [[https://element.io/][Element]] - Based on the Matrix protocol, offering decentralized, federated
149		chat. Great for groups and communities, with optional end-to-end encryption. A
150		little heavier on resources than the others.
151
152		Privacy-friendly messaging isn't perfect on iOS — background sync restrictions
153		and notification relay challenges exist — but these tools will cover most needs
154		while keeping your data away from corporate servers.
	131	chat. Great for groups and communities, with optional end-to-end encryption.
	132	Other client options are available for Matrix on iOS, as well.
155	133
156	134	#+begin_quote
157	135	I use: Signal for private chats with known people, and Matrix for group chats.
		@@ -160,8 +138,8 @@ while keeping your data away from corporate servers.
160	138	* VPNs & Networking
161	139
162	140	Network traffic is where most surveillance happens. Even with encrypted
163		messaging and browsers, your IP address and DNS queries reveal a lot. A good VPN
164		or alternative network routing tool masks this, but not all VPNs are
	141	messaging and browsers, your IP address and DNS queries reveal a lot about you.
	142	A good VPN or alternative network routing tool masks this, but not all VPNs are
165	143	trustworthy. Avoid “free” services or those lacking transparency.
166	144
167	145	- [[https://mullvad.net/][Mullvad]] - A no-logs VPN that doesn't require an email or personal info to
		@@ -174,10 +152,10 @@ trustworthy. Avoid “free” services or those lacking transparency.
174	152	polished for mobile but useful for hobbyists or building private networks
175	153	between devices.
176	154
177		If you can't self-host or build your own mesh, Mullvad is hands-down the
178		cleanest option here. There are other VPN options available, but I haven't
179		tested them all so I will simply put my vote for Mullvad here and let you
180		research other options if you don't want to use Mullvad.
	155	If you can't self-host or build your own mesh, Mullvad is hands-down the easiest
	156	option here. There are other VPN options available, but I haven't tested them
	157	all so I will simply put my vote for Mullvad here and let you research other
	158	options if you don't want to use Mullvad.
181	159
182	160	#+begin_quote
183	161	I use: Mullvad for 24/7 usage, and Tor when anonymity is required.
		@@ -185,12 +163,12 @@ research other options if you don't want to use Mullvad.
185	163
186	164	* Password Management
187	165
188		Weak, reused passwords are still one of the biggest risks for personal security.
189		A good password manager makes it possible to use strong, unique credentials
	166	Weak and reused passwords are still the biggest risks for personal security. A
	167	good password manager makes it possible to use strong, unique credentials
190	168	without memorizing them all.
191	169
192		- [[https://bitwarden.com/][Bitwarden]] - Open source, audited, and free to self-host. The iOS app
193		integrates with system autofill and Face ID. Solid for most users.
	170	- [[https://bitwarden.com/][Bitwarden]] - Open source, audited, and free to self-host (e.g., Vaultwarden).
	171	The iOS app integrates with system autofill and Face ID.
194	172	- [[https://keepassium.com/][KeePassium]] - A KeePass-compatible client for iOS. Local database storage,
195	173	optional cloud sync, and no external accounts. Excellent if you want full
196	174	control over your credential store.
		@@ -198,8 +176,8 @@ without memorizing them all.
198	176	your database with a secure method like [[https://cryptomator.org/][Cryptomator]]-protected cloud storage,
199	177	Syncthing, or local-only transfers.
200	178
201		Good password hygiene matters more than people realize, and these apps give you
202		control over your vault.
	179	Good passwords matter are extremely important, and these apps give you control
	180	over your vault.
203	181
204	182	#+begin_quote
205	183	I use: Bitwarden Families ($40/year) to protect passwords, passkeys, TOTP
		@@ -210,17 +188,20 @@ myself, I would prefer KeePassXC + Syncthing.
210	188	* Multi-Factor Authentication (MFA)
211	189
212	190	MFA is essential, but relying on SMS codes or untrusted proprietary apps defeats
213		the point. Use open, local, encrypted authenticators where possible.
	191	the point. Use open, local, encrypted authenticators where possible. Also, use
	192	passkeys if you can! I prefer passkeys, then TOTP, and then SMS/email, if other
	193	options are not possible.
214	194
215		- [[https://bitwarden.com/products/authenticator/][Bitwarden Authenticator]] - Integrates with the password manager or works
216		standalone. Encrypted backups through Bitwarden.
	195	- [[https://bitwarden.com/products/authenticator/][Bitwarden Authenticator]] - Integrates with the password manager or works as a
	196	standalone TOTP app. Optional encrypted backups through your Bitwarden
	197	account.
217	198	- [[https://ente.io/auth/][Ente Auth]] - Open source, end-to-end encrypted TOTP manager. Syncs encrypted
218	199	via Ente's infrastructure.
219	200	- [[https://www.tofuauth.com/][Tofu]] - Minimal, offline-first TOTP app. No cloud, no telemetry.
220	201	- [[https://raivo-otp.com/][Raivo OTP]] - Open source, native iOS app with secure iCloud backups. Clean
221	202	interface.
222	203	- [[https://apps.apple.com/us/app/otp-auth/id659877384][OTP Auth]] - A longstanding, trusted TOTP manager with encrypted backups and
223		Apple Watch support. Not open source.
	204	Apple Watch support. Not open source.
224	205
225	206	I recommend pairing one of these with strong passwords and a VPN for everyday
226	207	security.
		@@ -231,9 +212,8 @@ security.
231	212
232	213	* Notes & Personal Data
233	214
234		iCloud Notes and Google Keep aren't exactly privacy havens. If you're storing
235		sensitive personal notes, account details, or journal entries, opt for
236		encrypted, local-first apps.
	215	If you're storing sensitive personal notes, account details, or journal entries,
	216	opt for encrypted, local-first apps.
237	217
238	218	- [[https://beorgapp.com/][Beorg]] - An Org-mode-compatible outliner and task manager for iOS. Great for
239	219	Emacs fans and those managing plaintext files.
		@@ -248,15 +228,15 @@ These options help decouple your data from major cloud platforms while keeping
248	228	notes portable and encrypted.
249	229
250	230	#+begin_quote
251		I use: Beorg, since I love org-mode and no longer use markdown.
	231	I use: Beorg, since I love org-mode.
252	232	#+end_quote
253	233
254	234	* Photos & Media
255	235
256		Your camera roll quietly feeds metadata and images to iCloud by default. If you
257		want to self-host or encrypt your photo library, here's what works on iOS. At a
258		minimum, I suggest disabling iCloud for the Photos app, so the data stays local
259		on your device.
	236	If you're using iCloud Photos, your camera roll quietly feeds metadata and
	237	images to iCloud by default. If you want to self-host or encrypt your photo
	238	library, here's what works on iOS. At a minimum, I suggest disabling iCloud for
	239	the Photos app, so the data stays local on your device.
260	240
261	241	- [[https://immich.app/][Immich (self-hosted)]] - Open source, feature-rich, self-hosted photo manager
262	242	with facial recognition and live photo support. Requires a home server.
		@@ -290,14 +270,12 @@ require Instant PGP since Migadu's webmail client (SnappyMail) supports PGP.
290	270
291	271	* News & Social
292	272
293		Mainstream news and social apps leak all kinds of usage metadata, even when
294		you're just lurking. These tools let you follow content with less exposure.
	273	News and social apps leak all kinds of usage metadata, even when you're just
	274	lurking. These tools let you follow content with less exposure.
295	275
296		- [[https://netnewswire.com/][NetNewsWire]] - Free, open source RSS reader for iOS. Follow sites without
297		tracking.
298		- [[https://www.talklittle.com/three-cheers/][ThreeCheers]] - Privacy-friendly Reddit client for iOS. No official API calls,
299		built-in filtering.
300		- [[https://getvoyager.app/][Voyager]] - Clean, independent Mastodon client.
	276	- [[https://netnewswire.com/][NetNewsWire]] - Free, open source RSS reader for iOS.
	277	- [[https://www.talklittle.com/three-cheers/][ThreeCheers]] - Privacy-friendly Tildes client for iOS.
	278	- [[https://getvoyager.app/][Voyager]] - Clean, independent Lemmy client.
301	279	- [[https://joinmastodon.org/][Mastodon]] - Federated, open source alternative to Twitter.
302	280	- [[https://joinpeertube.org/][PeerTube]] - Decentralized video platform, accessible via web or PWA.
303	281	- [[https://pixelfed.org/][Pixelfed]] - Federated, open source alternative to Instagram.
		@@ -305,17 +283,23 @@ you're just lurking. These tools let you follow content with less exposure.
305	283	If you're going to be online, at least let it be on your terms.
306	284
307	285	#+begin_quote
308		I use: NetNewsWire (via FreshRSS) for RSS feeds, and Voyager for Lemmy. I have
309		used all of these apps and they are great, but I am not very active on social
310		sites.
	286	I use: NetNewsWire (via FreshRSS) for RSS feeds, Voyager for Lemmy, and Three
	287	Cheers for Tildes. I have used all of these apps and they are great, but I am
	288	not very active on social sites.
311	289	#+end_quote
312	290
313	291	* Final Thoughts
314	292
315		This isn't about paranoia — it's about awareness. Every app you use, every
316		service you sign into, quietly collects and trades your data. iOS makes true
317		anonymity harder than other platforms, but these tools and services give you a
318		fighting chance to keep your personal life personal.
	293	Whether you just want to improve your privacy in small steps or you're
	294	fashioning a tinfoil hat as we speak, moving to privacy-focused services and
	295	apps does two things:
	296
	297	1. It protects your privacy by ensuring that your data is being protected
	298	through the many methods mentioned above; and
	299	2. It provides money (for paid apps), support (in terms of download count,
	300	reviews, ratings, etc.), and motivation for the developers and companies
	301	behind these apps that provide a privacy haven for users on iOS.
319	302
320		If you have other privacy-friendly iOS tools you enjoy, [[mailto:hello@cleberg.net][email me]] — I'm always
321		looking for new things to test.
	303	Every app you use, every service you sign into, quietly collects and trades your
	304	data. iOS makes true anonymity harder than other platforms, but these tools and
	305	services give you a fighting chance to keep your data private.

content/blog/2025-06-27-how-blockchain-works.org deleted −197

		@@ -1,197 +0,0 @@
1		#+date: <2025-07-07 Mon 00:00:00>
2		#+title: Blockchain Series #1: How Blockchain Works Under the Hood: Hashes, Keys, and Signatures Explained
3		#+description: Dive into blockchain's cryptographic foundations. Explore how hash functions, Merkle trees, and digital signatures secure distributed, tamper-resistant ledgers.
4		#+slug: how-blockchain-works
5		#+filetags: :blockchain:encryption:
6		#+draft: t
7
8		/This is Part 1 of a series I'm writing on blockchain. Stay tuned for further
9		editions./
10
11		Blockchain is one of those technologies that seems to generate more marketing
12		buzz than real understanding. Everywhere you look, people talk about
13		decentralization, trustless systems, and the next big disruption. But beneath
14		the hype, blockchain systems rely on well-understood cryptographic building
15		blocks to do something very specific: maintain a secure, tamper-resistant ledger
16		without needing a central authority.
17
18		If you're serious about understanding blockchain, it's critical to understand
19		the cryptographic primitives that make it work. Hash functions, digital
20		signatures, and public-key cryptography aren't just jargon—they're the core
21		mechanisms that let a distributed network agree on a shared history no one can
22		easily rewrite.
23
24		This post is Part 1 of a multi-part series on blockchain. Here, we'll focus on
25		these fundamental building blocks—how they work, why they're used, and how they
26		fit together to provide the security and trust that blockchain promises.
27
28		* What is Blockchain?
29
30		At its core, a blockchain is a distributed, append-only ledger shared among
31		participants in a network.
32
33		What does this mean? Essentially, we can think of a standard, non-technical
34		ledger (book of accounts where transactions are recorded against accounts). When
35		introductin the idea of a blockchain, let's extend the idea of a standard ledger
36		and make a few connections:
37
38		- Each block of transactions is connected cryptographically to the block before
39		it, via a [[https://en.wikipedia.org/wiki/Cryptographic_hash_function][cryptographic hash]]. This is what forms a =chain= of blocks, or
40		records.
41		- Each block consists of:
42		- A list of validated transactions
43		- A timestamp
44		- A cryptographic hash of the previous block (ensuring immutability)
45		- Each transaction within a block is initiated between addresses, signed with
46		cryptographic keys, and sent to the blockchain for validation (e.g.,
47		proof-of-work, proof-of-staking, etc.).
48		- The blockchain is shared amongst nodes in the network, who agree on the state
49		of the blockchain through consensus mechanisms.
50
51		As we can see, the decentralized nature and cryptographic linking of
52		transactions and blocks ensures that modifying the history is infeasible.
53
54		If you're more of a visual person, here's a very basic diagram of a standard
55		blockchain structure.
56
57		#+begin_example
58		+------------+ +------------+ +------------+
59		\| Block 1 \| -> \| Block 2 \| -> \| Block 3 \|
60		\|------------\| \|------------\| \|------------\|
61		\| Data \| \| Data \| \| Data \|
62		\| Prev Hash: \| \| Prev Hash: \| \| Prev Hash: \|
63		\| 00000000 \| \| <hash1> \| \| <hash2> \|
64		\| Hash: \| \| Hash: \| \| Hash: \|
65		\| <hash1> \| \| <hash2> \| \| <hash3> \|
66		+------------+ +------------+ +------------+
67		#+end_example
68
69		* What Problems is Blockchain Trying to Solve?
70
71		I will be diving into the technical details of blockchains later in this post,
72		but what exactly is the reason blockchain exists?
73
74		You may know of cryptocurrencies, such as Bitcoin, but that is only one of many
75		use cases for blockchains.
76
77		As we learned in the section above, a blockchain can be equated to a ledger.
78		With this in mind, let's dive into a few interesting use cases:
79
80		** Immutable record-keeping
81
82		If you simply need a ledger that cannot be modified easily and can establish a
83		decentralized network to support that, blockchain is a great technology.
84
85		** Trust without central authority
86
87		The use of a decentralized system means that we do not need to rely on a
88		centralized authority (e.g., Social Security, a bank, etc.) to store and provide
89		access to information you need to record.
90
91		Think of the US Social Security Number (SSN) system. Each time you want to
92		perform actions that require verifying your identify (e.g., opening bank
93		accounts, investment accounts, child birth, etc.), you are currently required to
94		provide your SSN.
95
96		However, this is a singular number - which means that if someone learns it, they
97		can (essentially) now act as you.
98
99		Now imagine a scenario where the SSN system is a blockchain where you have both
100		your private key for providing evidence to people that you are you. For example,
101		you open a bank account and sign your form with your private key. Now, the bank
102		can take that and use your public key to decrypt the message and verify that you
103		are you, without needing to know your private key.
104
105		Another scenario is that, during a background check, a company could use your
106		public key and consult the related blockchain to validate specific pieces of
107		information. For example, if your identity alone is in one block, you could
108		provide that information to your employer without providing your full SSN and
109		all related personal information for as long as they keep your SSN on file.
110
111		** Double-spending problem
112
113		With the introduction of digital assets, such as cryptocurrencies and
114		non-fungible tokens, a new risk is introduced: without control, these assets
115		could be copied and reused at-will.
116
117		To solve this problem, digital assets are transacted on a blockchain to ensure
118		that the decentralized system of nodes provide consensus on validating
119		transactions, transactions are recorded in a transparent and tamper-resistant
120		manner, and cryptographic functions are performed to order the transactions
121		logically on chain.
122
123		* The Role of Cryptography in Blockchain
124		- Why cryptography matters
125		- Confidentiality vs. integrity/authenticity
126		- Core goals:
127		- Tamper-evidence
128		- Secure identification
129		- Non-repudiation
130
131		* Hash Functions
132		- What is a cryptographic hash?
133		- Properties:
134		- Collision resistance
135		- Pre-image resistance
136		- How blockchain uses hashes:
137		- Chaining blocks together
138		- Block headers
139		- Transactions
140		- Example command:
141		#+begin_src bash
142		echo -n "Hello, Blockchain" \| sha256sum
143		#+end_src
144		- Optional diagram: chain of blocks with hashes
145
146		* Merkle Trees
147		- Summarizing many transactions in a single root hash
148		- Use case: efficient inclusion proofs
149		- Example diagram (ASCII art if desired)
150		- Why Merkle roots are in block headers
151
152		* Public Key Cryptography
153		- Quick refresher
154		- Public/private keypairs
155		- Addresses derived from public keys
156		- Importance of keeping private keys secret
157
158		* Digital Signatures
159		- Purpose: proving authorship without revealing private key
160		- Mention ECDSA / EdDSA
161		- How transactions are signed
162		- Example snippet:
163		#+begin_example
164		Alice signs transaction with her private key
165		→ Anyone can verify with her public key
166		#+end_example
167		- Why signatures prevent forgery
168
169		* Bringing it All Together: Blockchain Data Structures
170		- Block structure:
171		- Block header with previous block's hash
172		- Merkle root
173		- Timestamp, nonce
174		- How the chain ensures immutability
175		- Example flow:
176		1. User creates a transaction
177		2. Signs it
178		3. Transaction included in block
179		4. Block hash links to previous block
180
181		* Proof of Work (Optional)
182		- Hash puzzles to add blocks
183		- Why it's hard to modify history
184		- Keep this section simple
185
186		* Conclusion
187		- Summarize how these primitives work together
188		- Tease next post: "Next, we'll explore security threats and how blockchain
189		networks mitigate them."
190		- Optional links to further reading:
191		- Bitcoin whitepaper
192		- Ethereum docs
193		- Cryptography references
194
195		* Optional Extras
196		- Glossary box with terms (hash, signature, Merkle tree)
197		- External references (e.g., NIST docs on hashes)

publish.el +9

		@@ -93,6 +93,15 @@
93	93	:output ".build/now/{{ slug }}.html"
94	94	:url "/now/{{ slug }}.html")
95	95
	96	;; About page route
	97	(weblorg-route
	98	:name "about"
	99	:input-pattern "content/about/*.org"
	100	:template "page.html"
	101	:output ".build/about/{{ slug }}.html"
	102	:url "/about/{{ slug }}.html")
	103
	104
96	105	;; RSS feed route
97	106	(weblorg-route
98	107	:name "rss"

theme/static/styles.css +12 −341

		@@ -1,318 +1,5 @@
1	1	/! normalize.css v8.0.1 \| MIT License \| github.com/necolas/normalize.css /
2
3		/* Document
4		========================================================================== */
5
6		/**
7		* 1. Correct the line height in all browsers.
8		* 2. Prevent adjustments of font size after orientation changes in iOS.
9		*/
10
11		html {
12		line-height: 1.15;
13		/* 1 */
14		-webkit-text-size-adjust: 100%;
15		/* 2 */
16		}
17
18		/* Sections
19		========================================================================== */
20
21		/**
22		* Render the `main` element consistently in IE.
23		*/
24
25		main {
26		display: block;
27		}
28
29		/**
30		* Correct the font size and margin on `h1` elements within `section` and
31		* `article` contexts in Chrome, Firefox, and Safari.
32		*/
33
34		h1 {
35		font-size: 2em;
36		margin: 0.67em 0;
37		}
38
39		/* Grouping content
40		========================================================================== */
41
42		/**
43		* 1. Add the correct box sizing in Firefox.
44		* 2. Show the overflow in Edge and IE.
45		*/
46
47		hr {
48		box-sizing: content-box;
49		/* 1 */
50		height: 0;
51		/* 1 */
52		overflow: visible;
53		/* 2 */
54		}
55
56		/* Text-level semantics
57		========================================================================== */
58
59		/**
60		* Remove the gray background on active links in IE 10.
61		*/
62
63		a {
64		background-color: transparent;
65		}
66
67		/**
68		* 1. Remove the bottom border in Chrome 57-
69		* 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.
70		*/
71
72		abbr[title] {
73		border-bottom: none;
74		/* 1 */
75		text-decoration: underline;
76		/* 2 */
77		text-decoration: underline dotted;
78		/* 2 */
79		}
80
81		/**
82		* Add the correct font weight in Chrome, Edge, and Safari.
83		*/
84
85		b,
86		strong {
87		font-weight: bolder;
88		}
89
90		/**
91		* Add the correct font size in all browsers.
92		*/
93
94		small {
95		font-size: 80%;
96		}
97
98		/**
99		* Prevent `sub` and `sup` elements from affecting the line height in
100		* all browsers.
101		*/
102
103		sub,
104		sup {
105		font-size: 75%;
106		line-height: 0;
107		position: relative;
108		vertical-align: baseline;
109		}
110
111		sub {
112		bottom: -0.25em;
113		}
114
115		sup {
116		top: -0.5em;
117		}
118
119		/* Forms
120		========================================================================== */
121
122		/**
123		* 1. Change the font styles in all browsers.
124		* 2. Remove the margin in Firefox and Safari.
125		*/
126
127		button,
128		input,
129		optgroup,
130		select,
131		textarea {
132		font-family: inherit;
133		/* 1 */
134		font-size: 100%;
135		/* 1 */
136		line-height: 1.15;
137		/* 1 */
138		margin: 0;
139		/* 2 */
140		}
141
142		/**
143		* Show the overflow in IE.
144		* 1. Show the overflow in Edge.
145		*/
146
147		button,
148		input {
149		/* 1 */
150		overflow: visible;
151		}
152
153		/**
154		* Remove the inheritance of text transform in Edge, Firefox, and IE.
155		* 1. Remove the inheritance of text transform in Firefox.
156		*/
157
158		button,
159		select {
160		/* 1 */
161		text-transform: none;
162		}
163
164		/**
165		* Correct the inability to style clickable types in iOS and Safari.
166		*/
167
168		button,
169		[type="button"],
170		[type="reset"],
171		[type="submit"] {
172		-webkit-appearance: button;
173		}
174
175		/**
176		* Remove the inner border and padding in Firefox.
177		*/
178
179		button::-moz-focus-inner,
180		[type="button"]::-moz-focus-inner,
181		[type="reset"]::-moz-focus-inner,
182		[type="submit"]::-moz-focus-inner {
183		border-style: none;
184		padding: 0;
185		}
186
187		/**
188		* Restore the focus styles unset by the previous rule.
189		*/
190
191		button:-moz-focusring,
192		[type="button"]:-moz-focusring,
193		[type="reset"]:-moz-focusring,
194		[type="submit"]:-moz-focusring {
195		outline: 1px dotted ButtonText;
196		}
197
198		/**
199		* Correct the padding in Firefox.
200		*/
201
202		fieldset {
203		padding: 0.35em 0.75em 0.625em;
204		}
205
206		/**
207		* 1. Correct the text wrapping in Edge and IE.
208		* 2. Correct the color inheritance from `fieldset` elements in IE.
209		* 3. Remove the padding so developers are not caught out when they zero out
210		* `fieldset` elements in all browsers.
211		*/
212
213		legend {
214		box-sizing: border-box;
215		/* 1 */
216		color: inherit;
217		/* 2 */
218		display: table;
219		/* 1 */
220		max-width: 100%;
221		/* 1 */
222		padding: 0;
223		/* 3 */
224		white-space: normal;
225		/* 1 */
226		}
227
228		/**
229		* Add the correct vertical alignment in Chrome, Firefox, and Opera.
230		*/
231
232		progress {
233		vertical-align: baseline;
234		}
235
236		/**
237		* Remove the default vertical scrollbar in IE 10+.
238		*/
239
240		textarea {
241		overflow: auto;
242		}
243
244		/**
245		* 1. Add the correct box sizing in IE 10.
246		* 2. Remove the padding in IE 10.
247		*/
248
249		[type="checkbox"],
250		[type="radio"] {
251		box-sizing: border-box;
252		/* 1 */
253		padding: 0;
254		/* 2 */
255		}
256
257		/**
258		* Correct the cursor style of increment and decrement buttons in Chrome.
259		*/
260
261		[type="number"]::-webkit-inner-spin-button,
262		[type="number"]::-webkit-outer-spin-button {
263		height: auto;
264		}
265
266		/**
267		* 1. Correct the odd appearance in Chrome and Safari.
268		* 2. Correct the outline style in Safari.
269		*/
270
271		[type="search"] {
272		-webkit-appearance: textfield;
273		/* 1 */
274		outline-offset: -2px;
275		/* 2 */
276		}
277
278		/**
279		* Remove the inner padding in Chrome and Safari on macOS.
280		*/
281
282		[type="search"]::-webkit-search-decoration {
283		-webkit-appearance: none;
284		}
285
286		/**
287		* 1. Correct the inability to style clickable types in iOS and Safari.
288		* 2. Change font properties to `inherit` in Safari.
289		*/
290
291		::-webkit-file-upload-button {
292		-webkit-appearance: button;
293		/* 1 */
294		font: inherit;
295		/* 2 */
296		}
297
298		/* Misc
299		========================================================================== */
300
301		/**
302		* Add the correct display in IE 10+.
303		*/
304
305		template {
306		display: none;
307		}
308
309		/**
310		* Add the correct display in IE 10.
311		*/
312
313		[hidden] {
314		display: none;
315		}
	2	html{line-height:1.15;-webkit-text-size-adjust:100%}main{display:block}h1{font-size:2em;margin:0.67em 0}hr{box-sizing:content-box;height:0;overflow:visible}a{background-color:transparent}abbr[title]{border-bottom:none;text-decoration:underline;text-decoration:underline dotted}b,strong{font-weight:bolder}small{font-size:80%}sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}sub{bottom:-0.25em}sup{top:-0.5em}button,input,optgroup,select,textarea{font-family:inherit;font-size:100%;line-height:1.15;margin:0}button,input{overflow:visible}button,select{text-transform:none}[type="button"],[type="reset"],[type="submit"],button{-webkit-appearance:button}[type="button"]::-moz-focus-inner,[type="reset"]::-moz-focus-inner,[type="submit"]::-moz-focus-inner,button::-moz-focus-inner{border-style:none;padding:0}[type="button"]:-moz-focusring,[type="reset"]:-moz-focusring,[type="submit"]:-moz-focusring,button:-moz-focusring{outline:1px dotted ButtonText}fieldset{padding:0.35em 0.75em 0.625em}legend{box-sizing:border-box;color:inherit;display:table;max-width:100%;padding:0;white-space:normal}progress{vertical-align:baseline}textarea{overflow:auto}[type="checkbox"],[type="radio"]{box-sizing:border-box;padding:0}[type="number"]::-webkit-inner-spin-button,[type="number"]::-webkit-outer-spin-button{height:auto}[type="search"]{-webkit-appearance:textfield;outline-offset:-2px}[type="search"]::-webkit-search-decoration{-webkit-appearance:none}::-webkit-file-upload-button{-webkit-appearance:button;font:inherit}template{display:none}[hidden]{display:none}
316	3
317	4	/* CUSTOM CSS */
318	5	:root {
		@@ -340,7 +27,7 @@ body {
340	27	Liberation Mono,
341	28	Lucida Console,
342	29	monospace;
343		font-size: clamp(0.95rem, 1vw + 0.5rem, 1.1rem);
	30	font-size: 1rem;
344	31	line-height: 1.5;
345	32	max-width: 50em;
346	33	margin: 0 auto;
		@@ -353,17 +40,12 @@ body {
353	40	}
354	41	}
355	42
356		main>+ {
357		margin-top: 2rem;
358		}
359
360	43	.site-nav,
361	44	footer {
362	45	border-color: var(--fg);
363	46	}
364	47
365	48	footer {
366		/* border-top: 1px dotted; */
367	49	padding-top: 1rem;
368	50	margin: 1rem 0;
369	51	}
		@@ -376,10 +58,6 @@ ul {
376	58	list-style-type: "- ";
377	59	}
378	60
379		/* .site-nav {
380		border-bottom: 1px dotted;
381		} */
382
383	61	.site-nav ul {
384	62	list-style-type: none;
385	63	display: flex;
		@@ -396,31 +74,25 @@ h2,
396	74	h3,
397	75	h4 {
398	76	color: var(--fg);
399		text-transform: uppercase;
400	77	}
401	78
402	79	h1 {
403		font-size: 2rem;
	80	font-size: 1.5rem;
404	81	font-weight: bold;
405		/* border-bottom: 1px solid var(--border); */
406		margin-top: 2rem;
407		margin-bottom: 1rem;
	82	margin-top: 1rem;
	83	margin-bottom: 0.75rem;
408	84	}
409	85
410	86	h2 {
411		font-size: 1.5rem;
412		margin-top: 1.5rem;
413		margin-bottom: .75rem;
414		}
415
416		h3 {
417	87	font-size: 1.25rem;
418		margin-top: 1.25rem;
419		margin-bottom: .5rem;
	88	margin-top: 1rem;
	89	margin-bottom: 0.5rem;
420	90	}
421	91
422		#text-table-of-contents li {
423		text-transform: uppercase;
	92	h3 {
	93	font-size: 1rem;
	94	margin-top: 1rem;
	95	margin-bottom: 0.25rem;
424	96	}
425	97
426	98	a,
		@@ -481,7 +153,7 @@ code {
481	153	Liberation Mono,
482	154	Lucida Console,
483	155	monospace;
484		font-size: inherit;
	156	font-size: 0.9rem;
485	157	}
486	158
487	159	pre {
		@@ -537,7 +209,6 @@ blockquote p {
537	209
538	210	.post-metadata {
539	211	border: 1px dotted var(--border);
540		/* border-top: none; */
541	212	padding: 1rem;
542	213	}
543	214

theme/templates/base.html +5 −4

		@@ -21,6 +21,7 @@
21	21	<nav class="site-nav" aria-label="site-nav" role="navigation">
22	22	<ul>
23	23	<li><a href="/">Home</a></li>
	24	<li><a href="/about/">About</a></li>
24	25	<li><a href="/blog/">Blog</a></li>
25	26	<li><a href="/services/">Services</a></li>
26	27	<li><a href="/wiki/">Wiki</a></li>
		@@ -28,16 +29,16 @@
28	29	</nav>
29	30	<main id="main">{% block main %}{% endblock %}</main>
30	31	<footer>
31		<p>Donate: <a href="ethereum:0x7850b2Fe6be94f90F54A099C74126430C9CeB19e">ETH</a>
	32	<p><a href="ethereum:0x7850b2Fe6be94f90F54A099C74126430C9CeB19e">ETH</a>
32	33	\| <a href="bitcoin:bc1qy74tcth6zwg88059ae9z3ghzk797fkav7zdx4k">BTC</a>
33	34	\| <a href="xrp:rJz78ahN1KmushjYjEnFd8CB5vCcreJ1EE">XRP</a>
34	35	</p>
35		<p>Last build: <<time datetime="{{ now() \| strftime("%Y-%m-%d") }}">{{ now() \| strftime("%Y-%m-%d %a %H:%M:%S") }}</time>></p>
	36	<p><<time datetime="{{ now() \| strftime("%Y-%m-%d") }}">{{ now() \| strftime("%Y-%m-%d %a %H:%M:%S") }}</time>></p>
36	37	<p>
37	38	<a href="https://stats.uptimerobot.com/OwOWs7HU0z">Status</a> ·
38	39	<a href="https://git.sr.ht/~cxc/cleberg.net" target="_blank"
39		rel="noopener">Source Code</a> ·
40		<a href="/feed.xml">RSS Feed</a> ·
	40	rel="noopener">Source</a> ·
	41	<a href="/feed.xml">RSS</a> ·
41	42	<a href="/.well-known/security.txt">security.txt</a>
42	43	</p>
43	44	<p>

theme/templates/blog.html +2 −1

		@@ -2,12 +2,13 @@
2	2	main %}
3	3	<h1>Blog</h1>
4	4	<p>
5		Use <code>⌘ + f</code> (<code>Ctrl + f</code>) to search blog post titles for
	5	Use <code>⌘ + f</code> (<code>Ctrl + f</code>) to search for
6	6	keywords.
7	7	</p>
8	8	<p>
9	9	You can also add the <a href="/feed.xml">RSS Feed</a> to your feed reader.
10	10	</p>
	11	<br>
11	12	{% for post in posts %}
12	13	<div class="post">
13	14	<time datetime='{{ post.date \| strftime("%Y-%m-%d") }}'

theme/templates/index.html +4 −15

		@@ -1,22 +1,22 @@
1	1	{% extends "base.html" %} {% block main %}
2	2	<section>
3		<h1><i>~cleberg.net</i></h1>
	3	<h1><i>~cmc</i></h1>
4	4	<pre>pub rsa4096 2022-11-16 [SC]
5	5	<a href="/gpg.txt">3917 973F B159 BBB8 6194 5385 6945 1A51 7AC0 CB37</a>
6	6	uid [ultimate] Christian Cleberg <hello@cleberg.net>
7	7	sub rsa4096 2022-11-16 [E]</pre>
8	8	</section>
9	9	<section>
10		<h2>Recent Blog Posts</h2>
	10	<h2>Blog Posts</h2>
11	11	<!-- BEGIN_POSTS -->
12	12	<!-- END_POSTS -->
13		<br>
14	13	<a href="/blog/">All Posts →</a>
15	14	</section>
16	15
17	16	<section>
18	17	<h2>Everything Else</h2>
19		<ul>
	18	<ul>
	19	<li><a href="/about/">About</a></li>
20	20	<li><a href="https://cv.cleberg.net">Curriculum Vitae</a></li>
21	21	<li><a href="/now/">Now</a></li>
22	22	<li><a href="/salary/">Salary</a></li>
		@@ -25,17 +25,6 @@ sub rsa4096 2022-11-16 [E]</pre>
25	25	</ul>
26	26	</section>
27	27
28		<section>
29		<h2>Contact</h2>
30		<ul>
31		<li><a href="mailto:hello@cleberg.net">hello@cleberg.net</a> (<a href="https://cleberg.net/gpg.txt">GPG</a>)</li>
32		<li><a href="https://lemmy.cleberg.net/u/cmc">@cmc</a> on Lemmy</li>
33		<li><a href="https://matrix.to/#/@cmc.:matrix.org">@cmc.:matrix.org</a> on Matrix</li>
34		<li>@cmc.01 on <a href="https://signal.org/">Signal</a></li>
35		<li><a href="https://sr.ht/~cxc">~cxc</a> on Sourcehut</li>
36		</ul>
37		</section>
38
39	28	<section class="hidden">
40	29	<div class="h-card">
41	30	<span class="p-name">Christian Cleberg</span>

Commit b021de29f4

Commit `b021de29f4`