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- New major version of coverage. sqlite storage, json report, contexts, relative filenames, dropped support for py 2.6/3.3/3.4.
- Compiled new sbsc requirements and updated the banner.
- Ordered a headset for the coding phone interviews where I need my hands to write.
- Remember js spread operator or rest parameter: …obj
- Played with coderpad to familiarize myself. Can write in many languages, set key bindings to vim, etc.
- Webcammed practice interview, both tech and worklife questions. ~20m/350MB@720.
- Placed grocery order with amazon (whole foods). Arrived a couple hours later.
- Citadel tech test was moved to first week of Jan when the proctor is back from holiday.
- Disney reached out for a senior software engineering position.
- Scheduled a phone call for later in the day.
- Spoke for 20min, discussing the opportunity.
- React/node/docker/mongo/k8s/aws/lambda.
- Exciting projects. Thrown right in. Move teams quite a bit.
- Almost all enter as contractors before full time. 50% insurance, no 401k. Paid hourly, but usually ~175k. No equity.
- Shorter hours.
- They’re an entertainment company before a tech company.
- Just one 30m coding call, then onsites.
- Review of old notes. Consume again and again, commit to memory.
- Bazel, c++, java. Lighter on python rules. Build and workspace files. Still similar to my old sx-setuptools, just files that take inputs and produce outputs. What files to build, what to do with it, etc.
- Computers perform tasks. Humans should be solving problems.
- Trees are just linked lists with multiple pointers, really. Graphs are just trees with no root.
- DP is generically named. Just solve subproblems and cache/memoize.
- C++ headers contain the declarations, source files use them.
- Polymorphism. Two children inheriting the parent but using a method/attribute differently (e.g. parent animal with noise() method, child cat would noise(‘meow’) and dog would noise(‘bark’)).
- let = block scoped. var = function scoped.
- Lists and dicts are basically the only mutables in python. All the primitives are immutable.
- Groovy is part of the java ecosystem.
- Python > byte code (pyc) > machine code.
- Netstat and wireshark.
- Can think of websockets as just persistent http connections with a server over tcp/ip, where a socket is any general tcp/ip connection.
- Every thread has its own stack (and registers), but all threads in the process share a heap.
- A$ap and chance most of today.
- Fed mouse.
- Went through Amazon’s leadership principles and wrote examples of each: https://www.amazon.jobs/en/principles. Having gone through all, examples came readily. The principles were generic.
- Received the online test for amazon. It takes 2 hours, and I can complete at any time in the next 2 weeks.
- The coding portion is 90m, 2 explicit “write a function that returns this” questions.
- I did a full demo test, finishing both after ~35min.
- They use Aspiring Minds (not codepen or google docs). No proctor.
- Asked Renee if it scores higher by submitting earlier, or if all extra time should be used improving/cleaning/commenting.
- Amazon has such a crazy list of products: https://aws.amazon.com/products/.
- Did some research and took some notes in gdrive. Main ones:
- EC2/Lambda for cloud servers and compute.
- Aurora/DocumentDB/ElastiCache/DynamoDB for all types of databases.
- Beanstalk/Amplify for building web/mobile apps.
- S3 for storage.
- Bought new bathroom and kitchen light bulbs.
- Run gym pull.
- Washed all mesh running shoes with soap.
- Scheduled haircut for thurs.
- Started reading ctci.
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- Disneyland yesterday. Club 33.
- Late picks: franky, cam.
- The ufc card last night was stacked but looooong.
- Patriots cheating again, confirmed shady footage of bengals sideline: https://twitter.com/FOXSports/status/1206265478596816896.
- Bamboolib is a python package which acts as a GUI for pandas. Kinda silly.
- Cleaned terrarium.
- Saw black christmas.
- Uncle Bill’s.
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- Metaflow is Netflix’ datascience kit, built on python/aws. It’s open-source now. https://metaflow.org/.
- Phase one trade agreement with china. The bidirectional tariffs that were going to start this sunday have been cancelled.
- Robinhood offers fractional shares now, down to $1.
- 3 coding interviews scheduled for next week so far: google, citadel, amazon. Netflix has passed on to hiring manager to schedule assessments next week, nothing on calendar yet.
- Eric got me a dexa scan, which I had wanted, but hadn’t mentioned!
- Great whites run away from orcas lol: https://www.smithsonianmag.com/smart-news/great-white-sharks-are-completely-terrified-orcas-180972009.
- Consolidated all my notes/stances. Some spacex, some political, some software, some personal. Many topics. 2 reasons: some are great responses for interview questions, some are great vlog topics.
- CLI for all unicode! https://github.com/arp242/uni.
- Apps use in-mem hash tables while databases used b-trees for persistent storage. https://www.evanjones.ca/ordered-vs-unordered-indexes.html.
- Read a bit more of PIE.
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- White elephant gift arrived in compton. It better get here by friday, ordered over two weeks ago.
- Remember paging secondary mem on disk.
- Livelock is like deadlock, but both the programs are changing state still (and still locking each time).
- Radix sort goes digit by digit, from LSD to MSD (tens -> hundreds etc). It’s faster than quicksort (linear vs nlogn) if the number of digits is low.
- Went over all the resources in the responses.
- Amazon leadership principles: https://www.amazon.jobs/en/principles. Important. Give example of each.
- For each interview, amazon has a “bar raiser” – someone who is not on the team that comes in to assess the general quality of the candidate.
- Citadel, google, notes.
- Checks can bounce after a few days. Federal law requires that the bank release the deposit to you sooner than some banks can actually clear the check. Be careful of scams.
- The office released the full 25min version of threat level midnight: https://www.youtube.com/watch?v=7iPyz6Yqwl4.
- Remember that an option can be exercised to get shares, but the contract for the options must be purchased as well (when traded on public markets, not like when your employer gifts you options). These contracts can be bought/sold.
- You usually have to put in a minimum amount into your account for short positions as collateral, since you can technically owe infinite amounts if things go south.
- Wrote a basic app for paul/ncl: https://gitlab.com/bmahlstedt/ncl.
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- Webcam arrived. No driver installation, just have to go into cheese (the gnome default webcam software) and change the device.
- Recorded 1min on 1920×1080. Was 53MB. Resolution was nice, but framerate was too low and the video was not smooth.
- Switched to 960×720. Still looks good, and is muuuuch less choppy.
- Picture res is set to 2304×1536.
- Autofocus is nice. Sound quality is good.
- Ask specifics during the “do you have any questions for me?” round. If you have a new idea, what’s the process for getting it approved for implementation? How many reorgs have happened in the last 5 years? How is software viewed by the other departments here?
- NAFTA = north american free trade agreement (us, mexico, canada = USMCA).
- Placed whole foods order.
- Made new batch (~5lbs) of protein bars, half pecan and half hazelnut. Added oats/sesameseed/cinnamon and a touch of water to make them less dry.
- Joe Pesci has some albums on spotify. Some are rap, some are christmas. What.
- 30m phone with netflix.
- Culture doc is accurate. Will scale as company does. https://jobs.netflix.com/culture.
- Instead of hiring in general then finding team fit (like google), they hire for a role specifically.
- This allows questions to be more focused, rather than generic DS&A.
- HR, then specific hiring manager, then take-home coding assessment, then onsites.
- Onsites have a tech round first. Mostly real-world problems, design. Then second round mostly culture, work scenarios, etc.
- Going to speak with the hiring manager for my role (CI) next wednesday the 18th.
- Emailed Holly’s friend Ben at GitLab.
- lol checked linkedin after, turns out he works at GitHub, not GitLab.
- Castle rock season finale. Loved the misery crossover.
- Committed sbsc lines and submitted picks.
- The new spreads failed for the first time. Just ssh in, make restart-prod, then try again from the admin interface.
- Talked with Paul about the ncl groundstation.
- Just a static template on aws right now, but want to be able to talk with the radio (bidirectionally) to show data and send commands. Went over flask, posting to endpoints, writing to db, etc.
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- Dec 15th US-China tariffs.
- Installed a bidet and separately did some sink plumbing.
- Bought spacers. Arriving tomorrow.
- ZYME shot back up 6.4% today.
- Retyping old investment notes for memory:
- Most common index funds: S&P500, DJIA (30 large cap), Russell 2000 (small cap).
- Mutual funds are not traded on exchanges, like regular stocks. They are pools of money that are collected from investors, then the asset managers choose the underlying securities for highest growth. Mutual funds are both an investment and a company.
- ETFs are exchange traded funds that you CAN trade like any regular old stock, and they track underlying index funds.
- Bull. Good. Rearing horns UPWARD. Bear. Bad. Swiping claws DOWNWARD.
- Money market funds are in things like government treasury bonds. Very low risk, low return (like a CD, little better than savings account).
- SPY is the ETF for S&P500, DIA is the ETF for DJIA.
- Hedge. Complement an investment with the opposite to reduce risk (and gains). Example: buy 1 stock for $100 and buy a $80 put option (year) for $5. If it goes up, you lose the $5 insurance policy but if it goes down, you can sell for $80 instead of $0.
- Derivatives are assets based on other assets, like a futures contract to hedge an initial buy, or options. They aren’t stock, but are derived from stock.
- Options. ISOs are like call options, buy at strike price and hope it goes up. Put options hope it goes down. If it drops, you buy the shares at the lower market price, then force the original contractor to honor the options and buy them from you at the higher price. Options have an expiration. Usually 1 put/call is for 100 shares, so a 50/50 hedge would be to buy 100 shares and buy 1 put.
- Futures. Like options, just an agreement to buy or sell at a future date, but you HAVE to fulfill the transaction. This is commonly done for raw materials to hedge.
- Shorting is betting on decrease. A put option is a short, a short position in futures is a short.
- Straddle. Buying a put and call option at the same strike/expiration. You profit if the price moves sharply in either direction.
- EPS = earnings per share. Not normalized, because a company can have an arbitrary number of shares.
- P/E = price earnings ratio. Normalized. Just the current price/eps. S&P is about 15. Higher doesn’t necessarily mean better; it can mean overvalued.
- Sharpe ratio is the risk-adjusted return. Basically take your average return (usually daily), subtract the risk-free return (usually 0), then divide by the standard deviation of returns, then annualize.
- Football scrimmage.
- False start = offense moves, ball is not hiked.
- Neutral zone infraction = defense moves, ball is not hiked.
- Encroachment = defender touches offender, ball is not hiked.
- Offsides = ball is hiked when defender is past line, free play.
- Remember belly breathing and 4-7-8.
- Amazon lost to Microsoft on a 10b/10y deal with the DoD for cloud services.
- Made new powders.
- Replenished sesame seeds, cinnamon, ground flax, and coffee beans.
- Ceylon over Cassia, much lower quantities of (toxic) coumarin.
- Brainstormed a few ideas/stances.
- Disabled abp/privacybadger/ublockorigin on lumen so gdrive would stop asking me to connect.
- A bit of interview question practice, mostly reading (Programming Interviews Exposed).
- Deployed new banner. Had asked a bunch of times but nothing yet. Compiled new reqs.
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- Got about 5 sentry errors last night, same thing about db connections failing when the server threads restart.
- The psycopg errors are all downstream. The actual error is that uwsgi is getting workers killed (sig 9) and trying to respawn. In looking through the digital ocean resource plots, it’s under heavy load.
- I believe the OOM killer is doing this deliberately. No error in the application itself. This will resolve once I self-host with a much better machine. No action for now.
- This also makes sense because it happens regularly ~sunday, 4 days after the application is restarted every wed for banner/lines.
- After a fantastic month, ZYME has dropped quite a bit over the past week.
- 30m with Citadel. (hi Jack!)
- Main is asset management, other business is market making (citadel securities).
- SRE positions open in securities, NY and Chicago.
- Umesh CTO: https://www.citadel.com/leadership/umesh-subramanian/.
- Finance is starting to pull a lot of people from big tech: google and such, not just jpmorgan and goldman sachs anymore. Not necessarily an 80-hr workweek industry anymore (although that’s what I’m used to).
- Comp is close to most parallel software positions. ~200 base and maybe 200 more target bonus (rather than equity).
- Work content is still finance, not quite the same purpose as spacex, but excitement from the challenge/community of tech colleagues.
- 20m with Google.
- Could do onsites in LA, even if the position is in the bay.
- Can expedite the interview process, skipping phones and moving straight to onsites.
- Process is basically the same as 2017. Refresh on algorithms and data structures.
- Type multiple times to remember. Most sorts are nlogn. Most searches are logn. Direct data structure operations on a hash table are usually constant. Space complexity for structures/searches are n. Space complexities for sorts are n, logn for quicksort, constant for bubble sort.
- For logn, each iteration is going to reduce the total by ~half. This is like binary search.
- For nlogn, it’s like quadratic, but instead of n*n, you still have to iterate over the whole thing once but each step reduces the remainder by half. This is like quicksort, mergesort, etc.
- 30m with Amazon.
- Hiring is usually isolated to a product (prime video in this case), but lateral movement is very possible within.
- 3 positions: software development engineer (mostly backend), frontend, webdev.
- You interview in general, then pick team after offer (same as google).
- Locations: santa monica and seattle. The recruiter called me from a 650 number!
- Java, python, react, js, aws.
- Prepare this week, tech phone interview next week (basic coding assessment, culture fit), onsites first week of jan (ds&a, system design, leadership).
- Tried a vlog recording with my raw laptop. Not great.
- The cam is at the bottom of the screen, not the top, so the keys/fingers are in frame unless the laptop is open well over 90deg. Mounting it would be weird.
- Resolution was pretty bad. Mic was quiet. Would definitely need to buy decent hardware for both.
- Recorded 2m raw, was 17MB (.webm). Goes to ~/Videos/Webcam
- Bought the logitech c920. Should have much better video and audio. Reviews say it should be fine with ubuntu. $58. Will test when it arrives wed.
- Tons of financial research. Instead of keeping here, added all to a new doc in my notes. Removed the old, elementary ones.
- DJIA, ETFs, SPY, MMMFs, hedging, futures, options, sharpe and other ratios.
- A Netflix recruiter reached out today as well. Set up phone call for tomorrow.
