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.title {text-wrap:balance;} 2017 solar eclipse—obscuration 93.8% (view original) In 2017, I opted to skip the crowds and the drive and settle for a 94% solar eclipse. I fully regret that decision. Weather permitting, I’ll be photographing the full solar eclipse from the path of totality next Monday. While I’ve amassed a ton of gear, the main resource I’ve dumped into this project is time—time planning, practicing, and hacking. After investing all that time, here’s my plan. Why I’m never going to produce an eclipse photo comparable to the work of Miloslav Druckmüller—so why bother with photography at all? Photography is my hobby, and what’s a hobby without a challenge? Sure, the siren song of cool gear is part of it—I do love gear—but it also takes planning, hacking, and editing skills to create a great picture. I got to spend time rooting around inside libgphoto2, breaking out the soldering iron to jury-rig a custom ESP32-based release cable, and practicing every move I’ll make on...
10 months ago

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More from Tyler Cipriani: blog

Eventually consistent plain text accounting

.title { text-wrap: balance } Spending for October, generated by piping hledger → R Over the past six months, I’ve tracked my money with hledger—a plain text double-entry accounting system written in Haskell. It’s been surprisingly painless. My previous attempts to pick up real accounting tools floundered. Hosted tools are privacy nightmares, and my stint with GnuCash didn’t last. But after stumbling on Dmitry Astapov’s “Full-fledged hledger” wiki1, it clicked—eventually consistent accounting. Instead of modeling your money all at once, take it one hacking session at a time. It should be easy to work towards eventual consistency. […] I should be able to [add financial records] bit by little bit, leaving things half-done, and picking them up later with little (mental) effort. – Dmitry Astapov, Full-Fledged Hledger Principles of my system I’ve cobbled together a system based on these principles: Avoid manual entry – Avoid typing in each transaction. Instead, rely on CSVs from the bank. CSVs as truth – CSVs are the only things that matter. Everything else can be blown away and rebuilt anytime. Embrace version control – Keep everything under version control in Git for easy comparison and safe experimentation. Learn hledger in five minutes hledger concepts are heady, but its use is simple. I divide the core concepts into two categories: Stuff hledger cares about: Transactions – how hledger moves money between accounts. Journal files – files full of transactions Stuff I care about: Rules files – how I set up accounts, import CSVs, and move money between accounts. Reports – help me see where my money is going and if I messed up my rules. Transactions move money between accounts: 2024-01-01 Payday income:work $-100.00 assets:checking $100.00 This transaction shows that on Jan 1, 2024, money moved from income:work into assets:checking—Payday. The sum of each transaction should be $0. Money comes from somewhere, and the same amount goes somewhere else—double-entry accounting. This is powerful technology—it makes mistakes impossible to ignore. Journal files are text files containing one or more transactions: 2024-01-01 Payday income:work $-100.00 assets:checking $100.00 2024-01-02 QUANSHENG UVK5 assets:checking $-29.34 expenses:fun:radio $29.34 Rules files transform CSVs into journal files via regex matching. Here’s a CSV from my bank: Transaction Date,Description,Category,Type,Amount,Memo 09/01/2024,DEPOSIT Paycheck,Payment,Payment,1000.00, 09/04/2024,PizzaPals Pizza,Food & Drink,Sale,-42.31, 09/03/2024,Amazon.com*XXXXXXXXY,Shopping,Sale,-35.56, 09/03/2024,OBSIDIAN.MD,Shopping,Sale,-10.00, 09/02/2024,Amazon web services,Personal,Sale,-17.89, And here’s a checking.rules to transform that CSV into a journal file so I can use it with hledger: # checking.rules # -------------- # Map CSV fields → hledger fields[0] fields date,description,category,type,amount,memo,_ # `account1`: the account for the whole CSV.[1] account1 assets:checking account2 expenses:unknown skip 1 date-format %m/%d/%Y currency $ if %type Payment account2 income:unknown if %category Food & Drink account2 expenses:food:dining # [0]: <https://hledger.org/hledger.html#field-names> # [1]: <https://hledger.org/hledger.html#account-field> With these two files (checking.rules and 2024-09_checking.csv), I can make the CSV into a journal: $ > 2024-09_checking.journal \ hledger print \ --rules-file checking.rules \ -f 2024-09_checking.csv $ head 2024-09_checking.journal 2024-09-01 DEPOSIT Paycheck assets:checking $1000.00 income:unknown $-1000.00 2024-09-02 Amazon web services assets:checking $-17.89 expenses:unknown $17.89 Reports are interesting ways to view transactions between accounts. There are registers, balance sheets, and income statements: $ hledger incomestatement \ --depth=2 \ --file=2024-09_bank.journal Revenues: $1000.00 income:unknown ----------------------- $1000.00 Expenses: $42.31 expenses:food $63.45 expenses:unknown ----------------------- $105.76 ----------------------- Net: $894.24 At the beginning of September, I spent $105.76 and made $1000, leaving me with $894.24. But a good chunk is going to the default expense account, expenses:unknown. I can use the hleger aregister to see what those transactions are: $ hledger areg expenses:unknown \ --file=2024-09_checking.journal \ -O csv | \ csvcut -c description,change | \ csvlook | description | change | | ------------------------ | ------ | | OBSIDIAN.MD | 10.00 | | Amazon web services | 17.89 | | Amazon.com*XXXXXXXXY | 35.56 | l Then, I can add some more rules to my checking.rules: if OBSIDIAN.MD account2 expenses:personal:subscriptions if Amazon web services account2 expenses:personal:web:hosting if Amazon.com account2 expenses:personal:shopping:amazon Now, I can reprocess my data to get a better picture of my spending: $ > 2024-09_bank.journal \ hledger print \ --rules-file bank.rules \ -f 2024-09_bank.csv $ hledger bal expenses \ --depth=3 \ --percent \ -f 2024-09_checking2.journal 30.0 % expenses:food:dining 33.6 % expenses:personal:shopping 9.5 % expenses:personal:subscriptions 16.9 % expenses:personal:web -------------------- 100.0 % For the Amazon.com purchase, I lumped it into the expenses:personal:shopping account. But I could dig deeper—download my order history from Amazon and categorize that spending. This is the power of working bit-by-bit—the data guides you to the next, deeper rabbit hole. Goals and non-goals Why am I doing this? For years, I maintained a monthly spreadsheet of account balances. I had a balance sheet. But I still had questions. Spending over six months, generated by piping hledger → gnuplot Before diving into accounting software, these were my goals: Granular understanding of my spending – The big one. This is where my monthly spreadsheet fell short. I knew I had money in the bank—I kept my monthly balance sheet. I budgeted up-front the % of my income I was saving. But I had no idea where my other money was going. Data privacy – I’m unwilling to hand the keys to my accounts to YNAB or Mint. Increased value over time – The more time I put in, the more value I want to get out—this is what you get from professional tools built for nerds. While I wished for low-effort setup, I wanted the tool to be able to grow to more uses over time. Non-goals—these are the parts I never cared about: Investment tracking – For now, I left this out of scope. Between monthly balances in my spreadsheet and online investing tools’ ability to drill down, I was fine.2 Taxes – Folks smarter than me help me understand my yearly taxes.3 Shared system – I may want to share reports from this system, but no one will have to work in it except me. Cash – Cash transactions are unimportant to me. I withdraw money from the ATM sometimes. It evaporates. hledger can track all these things. My setup is flexible enough to support them someday. But that’s unimportant to me right now. Monthly maintenance I spend about an hour a month checking in on my money Which frees me to spend time making fancy charts—an activity I perversely enjoy. Income vs. Expense, generated by piping hledger → gnuplot Here’s my setup: $ tree ~/Documents/ledger . ├── export │   ├── 2024-balance-sheet.txt │   └── 2024-income-statement.txt ├── import │   ├── in │   │   ├── amazon │   │   │   └── order-history.csv │   │   ├── credit │   │   │   ├── 2024-01-01_2024-02-01.csv │   │   │   ├── ... │   │   │   └── 2024-10-01_2024-11-01.csv │   │   └── debit │   │   ├── 2024-01-01_2024-02-01.csv │   │   ├── ... │   │   └── 2024-10-01_2024-11-01.csv │   └── journal │   ├── amazon │   │   └── order-history.journal │   ├── credit │   │   ├── 2024-01-01_2024-02-01.journal │   │   ├── ... │   │   └── 2024-10-01_2024-11-01.journal │   └── debit │   ├── 2024-01-01_2024-02-01.journal │   ├── ... │   └── 2024-10-01_2024-11-01.journal ├── rules │   ├── amazon │   │   └── journal.rules │   ├── credit │   │   └── journal.rules │   ├── debit │   │   └── journal.rules │   └── common.rules ├── 2024.journal ├── Makefile └── README Process: Import – download a CSV for the month from each account and plop it into import/in/<account>/<dates>.csv Make – run make Squint – Look at git diff; if it looks good, git add . && git commit -m "💸" otherwise review hledger areg to see details. The Makefile generates everything under import/journal: journal files from my CSVs using their corresponding rules. reports in the export folder I include all the journal files in the 2024.journal with the line: include ./import/journal/*/*.journal Here’s the Makefile: SHELL := /bin/bash RAW_CSV = $(wildcard import/in/**/*.csv) JOURNALS = $(foreach file,$(RAW_CSV),$(subst /in/,/journal/,$(patsubst %.csv,%.journal,$(file)))) .PHONY: all all: $(JOURNALS) hledger is -f 2024.journal > export/2024-income-statement.txt hledger bs -f 2024.journal > export/2024-balance-sheet.txt .PHONY clean clean: rm -rf import/journal/**/*.journal import/journal/%.journal: import/in/%.csv @echo "Processing csv $< to $@" @echo "---" @mkdir -p $(shell dirname $@) @hledger print --rules-file rules/$(shell basename $$(dirname $<))/journal.rules -f "$<" > "$@" If I find anything amiss (e.g., if my balances are different than what the bank tells me), I look at hleger areg. I may tweak my rules or my CSVs and then I run make clean && make and try again. Simple, plain text accounting made simple. And if I ever want to dig deeper, hledger’s docs have more to teach. But for now, the balance of effort vs. reward is perfect. while reading a blog post from Jonathan Dowland↩︎ Note, this is covered by full-fledged hledger – Investements↩︎ Also covered in full-fledged hledger – Tax returns↩︎

4 months ago 33 votes
Subliminal git commits

Luckily, I speak Leet. – Amita Ramanujan, Numb3rs, CBS’s IRC Drama There’s an episode of the CBS prime-time drama Numb3rs that plumbs the depths of Dr. Joel Fleischman’s1 knowledge of IRC. In one scene, Fleischman wonders, “What’s ‘leet’”? “Leet” is writing that replaces letters with numbers, e.g., “Numb3rs,” where 3 stands in for e. In short, leet is like the heavy-metal “S” you drew in middle school: Sweeeeet. / \ / | \ | | | \ \ | | | \ | / \ / ASCII art version of your misspent youth. Following years of keen observation, I’ve noticed Git commit hashes are also letters and numbers. Git commit hashes are, as Fleischman might say, prime targets for l33tification. What can I spell with a git commit? DenITDao via orlybooks) With hexidecimal we can spell any word containing the set of letters {A, B, C, D, E, F}—DEADBEEF (a classic) or ABBABABE (for Mama Mia aficionados). This is because hexidecimal is a base-16 numbering system—a single “digit” represents 16 numbers: Base-10: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 16 15 Base-16: 0 1 2 3 4 5 6 7 8 9 A B C D E F Leet expands our palette of words—using 0, 1, and 5 to represent O, I, and S, respectively. I created a script that scours a few word lists for valid words and phrases. With it, I found masterpieces like DADB0D (dad bod), BADA55 (bad ass), and 5ADBAB1E5 (sad babies). Manipulating commit hashes for fun and no profit Git commit hashes are no mystery. A commit hash is the SHA-1 of a commit object. And a commit object is the commit message with some metadata. $ mkdir /tmp/BADA55-git && cd /tmp/BAD55-git $ git init Initialized empty Git repository in /tmp/BADA55-git/.git/ $ echo '# BADA55 git repo' > README.md && git add README.md && git commit -m 'Initial commit' [main (root-commit) 68ec0dd] Initial commit 1 file changed, 1 insertion(+) create mode 100644 README.md $ git log --oneline 68ec0dd (HEAD -> main) Initial commit Let’s confirm we can recreate the commit hash: $ git cat-file -p 68ec0dd > commit-msg $ sha1sum <(cat \ <(printf "commit ") \ <(wc -c < commit-msg | tr -d '\n') \ <(printf '%b' '\0') commit-msg) 68ec0dd6dead532f18082b72beeb73bd828ee8fc /dev/fd/63 Our repo’s first commit has the hash 68ec0dd. My goal is: Make 68ec0dd be BADA55. Keep the commit message the same, visibly at least. But I’ll need to change the commit to change the hash. To keep those changes invisible in the output of git log, I’ll add a \t and see what happens to the hash. $ truncate -s -1 commit-msg # remove final newline $ printf '\t\n' >> commit-msg # Add a tab $ # Check the new SHA to see if it's BADA55 $ sha1sum <(cat \ <(printf "commit ") \ <(wc -c < commit-msg | tr -d '\n') \ <(printf '%b' '\0') commit-msg) 27b22ba5e1c837a34329891c15408208a944aa24 /dev/fd/63 Success! I changed the SHA-1. Now to do this until we get to BADA55. Fortunately, user not-an-aardvark created a tool for that—lucky-commit that manipulates a commit message, adding a combination of \t and [:space:] characters until you hit a desired SHA-1. Written in rust, lucky-commit computes all 256 unique 8-bit strings composed of only tabs and spaces. And then pads out commits up to 48-bits with those strings, using worker threads to quickly compute the SHA-12 of each commit. It’s pretty fast: $ time lucky_commit BADA555 real 0m0.091s user 0m0.653s sys 0m0.007s $ git log --oneline bada555 (HEAD -> main) Initial commit $ xxd -c1 <(git cat-file -p 68ec0dd) | grep -cPo ': (20|09)' 12 $ xxd -c1 <(git cat-file -p HEAD) | grep -cPo ': (20|09)' 111 Now we have an more than an initial commit. We have a BADA555 initial commit. All that’s left to do is to make ALL our commits BADA55 by abusing git hooks. $ cat > .git/hooks/post-commit && chmod +x .git/hooks/post-commit #!/usr/bin/env bash echo 'L337-ifying!' lucky_commit BADA55 $ echo 'A repo that is very l33t.' >> README.md && git commit -a -m 'l33t' L337-ifying! [main 0e00cb2] l33t 1 file changed, 1 insertion(+) $ git log --oneline bada552 (HEAD -> main) l33t bada555 Initial commit And now I have a git repo almost as cool as the sweet “S” I drew in middle school. This is a Northern Exposure spin off, right? I’ve only seen 1:48 of the show…↩︎ or SHA-256 for repos that have made the jump to a more secure hash function↩︎

4 months ago 47 votes
The Pull Request

A brief and biased history. Oh yeah, there’s pull requests now – GitHub blog, Sat, 23 Feb 2008 When GitHub launched, it had no code review. Three years after launch, in 2011, GitHub user rtomayko became the first person to make a real code comment, which read, in full: “+1”. Before that, GitHub lacked any way to comment on code directly. Instead, pull requests were a combination of two simple features: Cross repository compare view – a feature they’d debuted in 2010—git diff in a web page. A comments section – a feature most blogs had in the 90s. There was no way to thread comments, and the comments were on a different page than the diff. GitHub pull requests circa 2010. This is from the official documentation on GitHub. Earlier still, when the pull request debuted, GitHub claimed only that pull requests were “a way to poke someone about code”—a way to direct message maintainers, but one that lacked any web view of the code whatsoever. For developers, it worked like this: Make a fork. Click “pull request”. Write a message in a text form. Send the message to someone1 with a link to your fork. Wait for them to reply. In effect, pull requests were a limited way to send emails to other GitHub users. Ten years after this humble beginning—seven years after the first code comment—when Microsoft acquired GitHub for $7.5 Billion, this cobbled-together system known as “GitHub flow” had become the default way to collaborate on code via Git. And I hate it. Pull requests were never designed. They emerged. But not from careful consideration of the needs of developers or maintainers. Pull requests work like they do because they were easy to build. In 2008, GitHub’s developers could have opted to use git format-patch instead of teaching the world to juggle branches. Or they might have chosen to generate pull requests using the git request-pull command that’s existed in Git since 2005 and is still used by the Linux kernel maintainers today2. Instead, they shrugged into GitHub flow, and that flow taught the world to use Git. And commit histories have sucked ever since. For some reason, github has attracted people who have zero taste, don’t care about commit logs, and can’t be bothered. – Linus Torvalds, 2012 “Someone” was a person chosen by you from a checklist of the people who had also forked this repository at some point.↩︎ Though to make small, contained changes you’d use git format-patch and git am.↩︎

5 months ago 62 votes
Git the stupid password store

.title {text-wrap:balance;} GIT - the stupid content tracker “git” can mean anything, depending on your mood. – Linus Torvalds, Initial revision of “git”, the information manager from hell Like most git features, gitcredentials(7) are obscure, byzantine, and incredibly useful. And, for me, they’re a nice, hacky solution to a simple problem. Problem: Home directories teeming with tokens. Too many programs store cleartext credentials in config files in my home directory, making exfiltration all too easy. Solution: For programs I write, I can use git credential fill – the password library I never knew I installed. #!/usr/bin/env bash input="\ protocol=https host=example.com user=thcipriani " eval "$(echo "$input" | git credential fill)" echo "The password is: $password" Which looks like this when you run it: $ ./prompt.sh Password for 'https://thcipriani@example.com': The password is: hunter2 What did git credentials fill do? Accepted a protocol, username, and host on standard input. Called out to my git credential helper My credential helper checked for credentials matching https://thcipriani@example.com and found nothing Since my credential helper came up empty, it prompted me for my password Finally, it echoed <key>=<value>\n pairs for the keys protocol, host, username, and password to standard output. If I want, I can tell my credential helper to store the information I entered: git credential approve <<EOF protocol=$protocol username=$username host=$host password=$password EOF If I do that, the next time I run the script, it finds the password without prompting: $ ./prompt.sh The password is: hunter2 What are git credentials? Surprisingly, the intended purpose of git credentials is NOT “a weird way to prompt for passwords.” The problem git credentials solve is this: With git over ssh, you use your keys. With git over https, you type a password. Over and over and over. Beleaguered git maintainers solved this dilemma with the credential storage system—git credentials. With the right configuration, git will stop asking for your password when you push to an https remote. Instead, git credentials retrieve and send auth info to remotes. On the labyrinthine options of git credentials My mind initially refused to learn git credentials due to its twisty maze of terms that all sound alike: git credential fill: how you invoke a user’s configured git credential helper git credential approve: how you save git credentials (if this is supported by the user’s git credential helper) git credential.helper: the git config that points to a script that poops out usernames and passwords. These helper scripts are often named git-credential-<something>. git-credential-cache: a specific, built-in git credential helper that caches credentials in memory for a while. git-credential-store: STOP. DON’T TOUCH. This is a specific, built-in git credential helper that stores credentials in cleartext in your home directory. Whomp whomp. git-credential-manager: a specific and confusingly named git credential helper from Microsoft®. If you’re on Linux or Mac, feel free to ignore it. But once I mapped the terms, I only needed to pick a git credential helper. Configuring good credential helpers The built-in git-credential-store is a bad credential helper—it saves your passwords in cleartext in ~/.git-credentials.1 If you’re on a Mac, you’re in luck2—one command points git credentials to your keychain: git config --global credential.helper osxkeychain Third-party developers have contributed helpers for popular password stores: 1Password pass: the standard Unix password manager OAuth Git’s documentation contains a list of credential-helpers, too Meanwhile, Linux and Windows have standard options. Git’s source repo includes helpers for these options in the contrib directory. On Linux, you can use libsecret. Here’s how I configured it on Debian: sudo apt install libsecret-1-0 libsecret-1-dev cd /usr/share/doc/git/contrib/credential/libsecret/ sudo make sudo mv git-credential-libsecret /usr/local/bin/ git config --global credential.helper libsecret On Windows, you can use the confusingly named git credential manager. I have no idea how to do this, and I refuse to learn. Now, if you clone a repo over https, you can push over https without pain3. Plus, you have a handy trick for shell scripts. git-credential-store is not a git credential helper of honor. No highly-esteemed passwords should be stored with it. This message is a warning about danger. The danger is still present, in your time, as it was in ours.↩︎ I think. I only have Linux computers to test this on, sorry ;_;↩︎ Or the config option pushInsteadOf, which is what I actually do.↩︎

6 months ago 48 votes
Hexadecimal Sucks

Humans do no operate on hexadecimal symbols effectively […] there are exceptions. – Dan Kaminsky When SSH added ASCII art fingerprints (AKA, randomart), the author credited a talk by Dan Kaminsky. As a refresher, randomart looks like this: $ ssh-keygen -lv -f ~/.ssh/id_ed25519.pub 256 SHA256:XrvNnhQuG1ObprgdtPiqIGXUAsHT71SKh9/WAcAKoS0 thcipriani@foo.bar (ED25519) +--[ED25519 256]--+ | .++ ... | | o+.... o | |E .oo=.o . | | . .+.= . | | o= .S.o.o | | o o.o+.= + | | . . .o B * | | . . + & . | | ..+o*.= | +----[SHA256]-----+ Ben Cox describes the algorithm for generating random art on his blog. Here’s a slo-mo version of the algorithm in action: ASCII art ssh fingerprints slo-mo algorithm But in Dan’s talk, he never mentions anything about ASCII art. Instead, his talk was about exploiting our brain’s hardware acceleration to make it easier for us to recognize SSH fingerprints. The talk is worth watching, but I’ll attempt a summary. What’s the problem? We’ll never memorize SHA256:XrvNnhQuG1ObprgdtPiqIGXUAsHT71SKh9/WAcAKoS0—hexadecimal and base64 were built to encode large amounts of information rather than be easy to remember. But that’s ok for SSH keys because there are different kinds of memory: Rejection: I’ve never seen that before! Recognition: I know it’s that one—not the other one. Recollection: rote recall, like a phone number or address. For SSH you’ll use recognition—do you recognize this key? Of course, SSH keys are still a problem because our working memory is too small to recognize such long strings of letters and numbers. Hacks abound to shore up our paltry working memory—what Dan called “brain hardware acceleration.” Randomart attempts to tap into our hardware acceleration for pattern recognition—the visiuo-spacial sketchpad, where we store pictures. Dan’s idea tapped into a different aspect of hardware acceleration, one often cited by memory competition champions: chunking. Memory chunking and sha256 The web service what3words maps every three cubic meters (3m²) on Earth to three words. The White House’s Oval Office is ///curve.empty.buzz. Three words encode the same information as latitude and longitude—38.89, -77.03—chunking the information to be small enough to fit in our working memory. The mapping of locations to words uses a list of 40 thousand common English words, so each word encodes 15.29 bits of information—45.9 bits of information, identifying 64 trillion unique places. Meanwhile sha256 is 256 bits of information: ~116 quindecillion unique combinations. 64000000000000 # 64 trillion (what3words) 115792089237316195423570985008687907853269984665640564039457584007913129639936 # 116 (ish) quindecillion (sha256) For SHA256, we need more than three words or a dictionary larger than 40,000 words. Dan’s insight was we can identify SSH fingerprints using pairs of human names—couples. The math works like this1: 131,072 first names: 17 bits per name (×2) 524,288 last names: 19 bits per name 2,048 cities: 11 bits per city 17+17+19+11 = 64 bits With 64 bits per couple, you could uniquely identify 116 quindecillion items with four couples. Turning this: $ ssh foo.bar The authenticity of host 'foo.bar' can't be established. ED25519 key fingerprint is SHA256:XrvNnhQuG1ObprgdtPiqIGXUAsHT71SKh9/WAcAKoS0. Are you sure you want to continue connecting (yes/no/[fingerprint])? Into this2: $ ssh foo.bar The authenticity of host 'foo.bar' can't be established. SHA256:XrvNnhQuG1ObprgdtPiqIGXUAsHT71SKh9/WAcAKoS0 Key Data: Svasse and Tainen Jesudasson from Fort Wayne, Indiana, United States Illma and Sibeth Primack from Itārsi, Madhya Pradesh, India Maarja and Nisim Balyeat from Mukilteo, Washington, United States Hsu-Heng and Rasim Haozi from Manali, Tamil Nadu, India Are you sure you want to continue connecting (yes/no/[fingerprint])? With enough exposure, building recognition for these names and places should be possible—at least more possible than memorizing host keys. I’ve modified this from the original talk, in 2006 we were using md5 fingerprints of 160-bits. Now we’re using 256-bit fingerprints, so we needed to encode even more information, but the idea still works.↩︎ A (very) rough code implementation is on my github.↩︎

8 months ago 58 votes

More in programming

Diagnosis in engineering strategy.

Once you’ve written your strategy’s exploration, the next step is working on its diagnosis. Diagnosis is understanding the constraints and challenges your strategy needs to address. In particular, it’s about doing that understanding while slowing yourself down from deciding how to solve the problem at hand before you know the problem’s nuances and constraints. If you ever find yourself wanting to skip the diagnosis phase–let’s get to the solution already!–then maybe it’s worth acknowledging that every strategy that I’ve seen fail, did so due to a lazy or inaccurate diagnosis. It’s very challenging to fail with a proper diagnosis, and almost impossible to succeed without one. The topics this chapter will cover are: Why diagnosis is the foundation of effective strategy, on which effective policy depends. Conversely, how skipping the diagnosis phase consistently ruins strategies A step-by-step approach to diagnosing your strategy’s circumstances How to incorporate data into your diagnosis effectively, and where to focus on adding data Dealing with controversial elements of your diagnosis, such as pointing out that your own executive is one of the challenges to solve Why it’s more effective to view difficulties as part of the problem to be solved, rather than a blocking issue that prevents making forward progress The near impossibility of an effective diagnosis if you don’t bring humility and self-awareness to the process Into the details we go! This is an exploratory, draft chapter for a book on engineering strategy that I’m brainstorming in #eng-strategy-book. As such, some of the links go to other draft chapters, both published drafts and very early, unpublished drafts. Diagnosis is strategy’s foundation One of the challenges in evaluating strategy is that, after the fact, many effective strategies are so obvious that they’re pretty boring. Similarly, most ineffective strategies are so clearly flawed that their authors look lazy. That’s because, as a strategy is operated, the reality around it becomes clear. When you’re writing your strategy, you don’t know if you can convince your colleagues to adopt a new approach to specifying APIs, but a year later you know very definitively whether it’s possible. Building your strategy’s diagnosis is your attempt to correctly recognize the context that the strategy needs to solve before deciding on the policies to address that context. Done well, the subsequent steps of writing strategy often feel like an afterthought, which is why I think of diagnosis as strategy’s foundation. Where exploration was an evaluation-free activity, diagnosis is all about evaluation. How do teams feel today? Why did that project fail? Why did the last strategy go poorly? What will be the distractions to overcome to make this new strategy successful? That said, not all evaluation is equal. If you state your judgment directly, it’s easy to dispute. An effective diagnosis is hard to argue against, because it’s a web of interconnected observations, facts, and data. Even for folks who dislike your conclusions, the weight of evidence should be hard to shift. Strategy testing, explored in the Refinement section, takes advantage of the reality that it’s easier to diagnose by doing than by speculating. It proposes a recursive diagnosis process until you have real-world evidence that the strategy is working. How to develop your diagnosis Your strategy is almost certain to fail unless you start from an effective diagnosis, but how to build a diagnosis is often left unspecified. That’s because, for most folks, building the diagnosis is indeed a dark art: unspecified, undiscussion, and uncontrollable. I’ve been guilty of this as well, with The Engineering Executive’s Primer’s chapter on strategy staying silent on the details of how to diagnose for your strategy. So, yes, there is some truth to the idea that forming your diagnosis is an emergent, organic process rather than a structured, mechanical one. However, over time I’ve come to adopt a fairly structured approach: Braindump, starting from a blank sheet of paper, write down your best understanding of the circumstances that inform your current strategy. Then set that piece of paper aside for the moment. Summarize exploration on a new piece of paper, review the contents of your exploration. Pull in every piece of diagnosis from similar situations that resonates with you. This is true for both internal and external works! For each diagnosis, tag whether it fits perfectly, or needs to be adjusted for your current circumstances. Then, once again, set the piece of paper aside. Mine for distinct perspectives on yet another blank page, talking to different stakeholders and colleagues who you know are likely to disagree with your early thinking. Your goal is not to agree with this feedback. Instead, it’s to understand their view. The Crux by Richard Rumelt anchors diagnosis in this approach, emphasizing the importance of “testing, adjusting, and changing the frame, or point of view.” Synthesize views into one internally consistent perspective. Sometimes the different perspectives you’ve gathered don’t mesh well. They might well explicitly differ in what they believe the underlying problem is, as is typical in tension between platform and product engineering teams. The goal is to competently represent each of these perspectives in the diagnosis, even the ones you disagree with, so that later on you can evaluate your proposed approach against each of them. When synthesizing feedback goes poorly, it tends to fail in one of two ways. First, the author’s opinion shines through so strongly that it renders the author suspect. Your goal is never to agree with every team’s perspective, just as your diagnosis should typically avoid crowning any perspective as correct: a reader should generally be appraised of the details and unaware of the author. The second common issue is when a group tries to jointly own the synthesis, but create a fractured perspective rather than a unified one. I generally find that having one author who is accountable for representing all views works best to address both of these issues. Test drafts across perspectives. Once you’ve written your initial diagnosis, you want to sit down with the people who you expect to disagree most fervently. Iterate with them until they agree that you’ve accurately captured their perspective. It might be that they disagree with some other view points, but they should be able to agree that others hold those views. They might argue that the data you’ve included doesn’t capture their full reality, in which case you can caveat the data by saying that their team disagrees that it’s a comprehensive lens. Don’t worry about getting the details perfectly right in your initial diagnosis. You’re trying to get the right crumbs to feed into the next phase, strategy refinement. Allowing yourself to be directionally correct, rather than perfectly correct, makes it possible to cover a broad territory quickly. Getting caught up in perfecting details is an easy way to anchor yourself into one perspective prematurely. At this point, I hope you’re starting to predict how I’ll conclude any recipe for strategy creation: if these steps feel overly mechanical to you, adjust them to something that feels more natural and authentic. There’s no perfect way to understand complex problems. That said, if you feel uncertain, or are skeptical of your own track record, I do encourage you to start with the above approach as a launching point. Incorporating data into your diagnosis The strategy for Navigating Private Equity ownership’s diagnosis includes a number of details to help readers understand the status quo. For example the section on headcount growth explains headcount growth, how it compares to the prior year, and providing a mental model for readers to translate engineering headcount into engineering headcount costs: Our Engineering headcount costs have grown by 15% YoY this year, and 18% YoY the prior year. Headcount grew 7% and 9% respectively, with the difference between headcount and headcount costs explained by salary band adjustments (4%), a focus on hiring senior roles (3%), and increased hiring in higher cost geographic regions (1%). If everyone evaluating a strategy shares the same foundational data, then evaluating the strategy becomes vastly simpler. Data is also your mechanism for supporting or critiquing the various views that you’ve gathered when drafting your diagnosis; to an impartial reader, data will speak louder than passion. If you’re confident that a perspective is true, then include a data narrative that supports it. If you believe another perspective is overstated, then include data that the reader will require to come to the same conclusion. Do your best to include data analysis with a link out to the full data, rather than requiring readers to interpret the data themselves while they are reading. As your strategy document travels further, there will be inevitable requests for different cuts of data to help readers understand your thinking, and this is somewhat preventable by linking to your original sources. If much of the data you want doesn’t exist today, that’s a fairly common scenario for strategy work: if the data to make the decision easy already existed, you probably would have already made a decision rather than needing to run a structured thinking process. The next chapter on refining strategy covers a number of tools that are useful for building confidence in low-data environments. Whisper the controversial parts At one time, the company I worked at rolled out a bar raiser program styled after Amazon’s, where there was an interviewer from outside the team that had to approve every hire. I spent some time arguing against adding this additional step as I didn’t understand what we were solving for, and I was surprised at how disinterested management was about knowing if the new process actually improved outcomes. What I didn’t realize until much later was that most of the senior leadership distrusted one of their peers, and had rolled out the bar raiser program solely to create a mechanism to control that manager’s hiring bar when the CTO was disinterested holding that leader accountable. (I also learned that these leaders didn’t care much about implementing this policy, resulting in bar raiser rejections being frequently ignored, but that’s a discussion for the Operations for strategy chapter.) This is a good example of a strategy that does make sense with the full diagnosis, but makes little sense without it, and where stating part of the diagnosis out loud is nearly impossible. Even senior leaders are not generally allowed to write a document that says, “The Director of Product Engineering is a bad hiring manager.” When you’re writing a strategy, you’ll often find yourself trying to choose between two awkward options: Say something awkward or uncomfortable about your company or someone working within it Omit a critical piece of your diagnosis that’s necessary to understand the wider thinking Whenever you encounter this sort of debate, my advice is to find a way to include the diagnosis, but to reframe it into a palatable statement that avoids casting blame too narrowly. I think it’s helpful to discuss a few concrete examples of this, starting with the strategy for navigating private equity, whose diagnosis includes: Based on general practice, it seems likely that our new Private Equity ownership will expect us to reduce R&D headcount costs through a reduction. However, we don’t have any concrete details to make a structured decision on this, and our approach would vary significantly depending on the size of the reduction. There are many things the authors of this strategy likely feel about their state of reality. First, they are probably upset about the fact that their new private equity ownership is likely to eliminate colleagues. Second, they are likely upset that there is no clear plan around what they need to do, so they are stuck preparing for a wide range of potential outcomes. However they feel, they don’t say any of that, they stick to precise, factual statements. For a second example, we can look to the Uber service migration strategy: Within infrastructure engineering, there is a team of four engineers responsible for service provisioning today. While our organization is growing at a similar rate as product engineering, none of that additional headcount is being allocated directly to the team working on service provisioning. We do not anticipate this changing. The team didn’t agree that their headcount should not be growing, but it was the reality they were operating in. They acknowledged their reality as a factual statement, without any additional commentary about that statement. In both of these examples, they found a professional, non-judgmental way to acknowledge the circumstances they were solving. The authors would have preferred that the leaders behind those decisions take explicit accountability for them, but it would have undermined the strategy work had they attempted to do it within their strategy writeup. Excluding critical parts of your diagnosis makes your strategies particularly hard to evaluate, copy or recreate. Find a way to say things politely to make the strategy effective. As always, strategies are much more about realities than ideals. Reframe blockers as part of diagnosis When I work on strategy with early-career leaders, an idea that comes up a lot is that an identified problem means that strategy is not possible. For example, they might argue that doing strategy work is impossible at their current company because the executive team changes their mind too often. That core insight is almost certainly true, but it’s much more powerful to reframe that as a diagnosis: if we don’t find a way to show concrete progress quickly, and use that to excite the executive team, our strategy is likely to fail. This transforms the thing preventing your strategy into a condition your strategy needs to address. Whenever you run into a reason why your strategy seems unlikely to work, or why strategy overall seems difficult, you’ve found an important piece of your diagnosis to include. There are never reasons why strategy simply cannot succeed, only diagnoses you’ve failed to recognize. For example, we knew in our work on Uber’s service provisioning strategy that we weren’t getting more headcount for the team, the product engineering team was going to continue growing rapidly, and that engineering leadership was unwilling to constrain how product engineering worked. Rather than preventing us from implementing a strategy, those components clarified what sort of approach could actually succeed. The role of self-awareness Every problem of today is partially rooted in the decisions of yesterday. If you’ve been with your organization for any duration at all, this means that you are directly or indirectly responsible for a portion of the problems that your diagnosis ought to recognize. This means that recognizing the impact of your prior actions in your diagnosis is a powerful demonstration of self-awareness. It also suggests that your next strategy’s success is rooted in your self-awareness about your prior choices. Don’t be afraid to recognize the failures in your past work. While changing your mind without new data is a sign of chaotic leadership, changing your mind with new data is a sign of thoughtful leadership. Summary Because diagnosis is the foundation of effective strategy, I’ve always found it the most intimidating phase of strategy work. While I think that’s a somewhat unavoidable reality, my hope is that this chapter has somewhat prepared you for that challenge. The four most important things to remember are simply: form your diagnosis before deciding how to solve it, try especially hard to capture perspectives you initially disagree with, supplement intuition with data where you can, and accept that sometimes you’re missing the data you need to fully understand. The last piece in particular, is why many good strategies never get shared, and the topic we’ll address in the next chapter on strategy refinement.

10 hours ago 3 votes
My friend, JT

I’ve had a cat for almost a third of my life.

2 hours ago 3 votes
[Course Launch] Hands-on Introduction to X86 Assembly

A Live, Interactive Course for Systems Engineers

5 hours ago 2 votes
It’s cool to care

I’m sitting in a small coffee shop in Brooklyn. I have a warm drink, and it’s just started to snow outside. I’m visiting New York to see Operation Mincemeat on Broadway – I was at the dress rehearsal yesterday, and I’ll be at the opening preview tonight. I’ve seen this show more times than I care to count, and I hope US theater-goers love it as much as Brits. The people who make the show will tell you that it’s about a bunch of misfits who thought they could do something ridiculous, who had the audacity to believe in something unlikely. That’s certainly one way to see it. The musical tells the true story of a group of British spies who tried to fool Hitler with a dead body, fake papers, and an outrageous plan that could easily have failed. Decades later, the show’s creators would mirror that same spirit of unlikely ambition. Four friends, armed with their creativity, determination, and a wardrobe full of hats, created a new musical in a small London theatre. And after a series of transfers, they’re about to open the show under the bright lights of Broadway. But when I watch the show, I see a story about friendship. It’s about how we need our friends to help us, to inspire us, to push us to be the best versions of ourselves. I see the swaggering leader who needs a team to help him truly achieve. The nervous scientist who stands up for himself with the support of his friends. The enthusiastic secretary who learns wisdom and resilience from her elder. And so, I suppose, it’s fitting that I’m not in New York on my own. I’m here with friends – dozens of wonderful people who I met through this ridiculous show. At first, I was just an audience member. I sat in my seat, I watched the show, and I laughed and cried with equal measure. After the show, I waited at stage door to thank the cast. Then I came to see the show a second time. And a third. And a fourth. After a few trips, I started to see familiar faces waiting with me at stage door. So before the cast came out, we started chatting. Those conversations became a Twitter community, then a Discord, then a WhatsApp. We swapped fan art, merch, and stories of our favourite moments. We went to other shows together, and we hung out outside the theatre. I spent New Year’s Eve with a few of these friends, sitting on somebody’s floor and laughing about a bowl of limes like it was the funniest thing in the world. And now we’re together in New York. Meeting this kind, funny, and creative group of people might seem as unlikely as the premise of Mincemeat itself. But I believed it was possible, and here we are. I feel so lucky to have met these people, to take this ridiculous trip, to share these precious days with them. I know what a privilege this is – the time, the money, the ability to say let’s do this and make it happen. How many people can gather a dozen friends for even a single evening, let alone a trip halfway round the world? You might think it’s silly to travel this far for a theatre show, especially one we’ve seen plenty of times in London. Some people would never see the same show twice, and most of us are comfortably into double or triple-figures. Whenever somebody asks why, I don’t have a good answer. Because it’s fun? Because it’s moving? Because I enjoy it? I feel the need to justify it, as if there’s some logical reason that will make all of this okay. But maybe I don’t have to. Maybe joy doesn’t need justification. A theatre show doesn’t happen without people who care. Neither does a friendship. So much of our culture tells us that it’s not cool to care. It’s better to be detached, dismissive, disinterested. Enthusiasm is cringe. Sincerity is weakness. I’ve certainly felt that pressure – the urge to play it cool, to pretend I’m above it all. To act as if I only enjoy something a “normal” amount. Well, fuck that. I don’t know where the drive to be detached comes from. Maybe it’s to protect ourselves, a way to guard against disappointment. Maybe it’s to seem sophisticated, as if having passions makes us childish or less mature. Or perhaps it’s about control – if we stay detached, we never have to depend on others, we never have to trust in something bigger than ourselves. Being detached means you can’t get hurt – but you’ll also miss out on so much joy. I’m a big fan of being a big fan of things. So many of the best things in my life have come from caring, from letting myself be involved, from finding people who are a big fan of the same things as me. If I pretended not to care, I wouldn’t have any of that. Caring – deeply, foolishly, vulnerably – is how I connect with people. My friends and I care about this show, we care about each other, and we care about our joy. That care and love for each other is what brought us together, and without it we wouldn’t be here in this city. I know this is a once-in-a-lifetime trip. So many stars had to align – for us to meet, for the show we love to be successful, for us to be able to travel together. But if we didn’t care, none of those stars would have aligned. I know so many other friends who would have loved to be here but can’t be, for all kinds of reasons. Their absence isn’t for lack of caring, and they want the show to do well whether or not they’re here. I know they care, and that’s the important thing. To butcher Tennyson: I think it’s better to care about something you cannot affect, than to care about nothing at all. In a world that’s full of cynicism and spite and hatred, I feel that now more than ever. I’d recommend you go to the show if you haven’t already, but that’s not really the point of this post. Maybe you’ve already seen Operation Mincemeat, and it wasn’t for you. Maybe you’re not a theatre kid. Maybe you aren’t into musicals, or history, or war stories. That’s okay. I don’t mind if you care about different things to me. (Imagine how boring the world would be if we all cared about the same things!) But I want you to care about something. I want you to find it, find people who care about it too, and hold on to them. Because right now, in this city, with these people, at this show? I’m so glad I did. And I hope you find that sort of happiness too. Some of the people who made this trip special. Photo by Chloe, and taken from her Twitter. Timing note: I wrote this on February 15th, but I delayed posting it because I didn’t want to highlight the fact I was away from home. [If the formatting of this post looks odd in your feed reader, visit the original article]

yesterday 4 votes
Stick with the customer

One of the biggest mistakes that new startup founders make is trying to get away from the customer-facing roles too early. Whether it's customer support or it's sales, it's an incredible advantage to have the founders doing that work directly, and for much longer than they find comfortable. The absolute worst thing you can do is hire a sales person or a customer service agent too early. You'll miss all the golden nuggets that customers throw at you for free when they're rejecting your pitch or complaining about the product. Seeing these reasons paraphrased or summarized destroy all the nutrients in their insights. You want that whole-grain feedback straight from the customers' mouth!  When we launched Basecamp in 2004, Jason was doing all the customer service himself. And he kept doing it like that for three years!! By the time we hired our first customer service agent, Jason was doing 150 emails/day. The business was doing millions of dollars in ARR. And Basecamp got infinitely, better both as a market proposition and as a product, because Jason could funnel all that feedback into decisions and positioning. For a long time after that, we did "Everyone on Support". Frequently rotating programmers, designers, and founders through a day of answering emails directly to customers. The dividends of doing this were almost as high as having Jason run it all in the early years. We fixed an incredible number of minor niggles and annoying bugs because programmers found it easier to solve the problem than to apologize for why it was there. It's not easy doing this! Customers often offer their valuable insights wrapped in rude language, unreasonable demands, and bad suggestions. That's why many founders quit the business of dealing with them at the first opportunity. That's why few companies ever do "Everyone On Support". That's why there's such eagerness to reduce support to an AI-only interaction. But quitting dealing with customers early, not just in support but also in sales, is an incredible handicap for any startup. You don't have to do everything that every customer demands of you, but you should certainly listen to them. And you can't listen well if the sound is being muffled by early layers of indirection.

yesterday 4 votes