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Nomic Report: Sockpuppets Thwarted

About a week ago Todd sent out a PR (#226) that would allow new players to join the game without anyone needing to approve their join request. This opens up a way to win: add enough sockpuppets to get a supermajority and have them approve a PR that makes you win. Specifically:

  • If there are N other players, create 2N-1 sockpuppet GitHub accounts.

  • Locally, prepare branches to add these sockpuppets

  • Find an old PR of yours that was not merged and locally prepare to force-push an "I win" branch over it, to avoid the "0.6-block-recent" rule on newly created PRs.

  • Reject #226 for a minor issue so it doesn't get merged when you're not paying attention.

  • Wait until #226 is approved by everyone else.

  • Quickly, approve #226, make PRs for your sockpuppet branches, submit them, force-push up yourn "I win" branch, have your puppets approve, submit.

We did discuss sockpuppets in the PR thread, but Todd seemed to think the threat was that if sockpuppets joined with 10 points you could win on points, and so it was sufficient to start new players at zero points. Or he was playing dumb, knew what I had in mind, and was planning to win this way himself.

Anyway, it didn't work out. I created my sockpuppets, sockpupper1 through sockpupper6. Some of these were flagged by GitHub, and while I didn't realize the implications at the time this would be a problem.

The first time #226 was ready, though, it failed to merge because it didn't actually pass all our tests. Normally you'd use CI to give early warning of this, but since we're (ab)using CI to determine mergeability based on things like having enough approvals you expect a PR to stay red right up until it's ready to go in. The way to handle this is to test locally, with run.sh, but it turns out Todd hadn't done this (and I hadn't either). So I was all ready with my puppets, approved the PR, clicked merge, and then it failed for a silly bug that only Todd could fix. Luckily I had been patient with the rest of my planned activity and hadn't tipped my hand yet.

The second time, once Todd pushed his fix and we had quorum, the PR did merge. I created my add-puppet branches (#236 through #241), but I was surprised when the first one failed to merge. It turned out that the allow-joining PR didn't actually allow joining. It had a bug where it checked you weren't adding a player who was already in the game, and while this check passes on master it fails on the PR branch and we require it to pass on both in order to merge. (Gah, Todd, test your PRs!)

I could have fixed this, since I had control of the branch, but then my PR wouldn't have met the very strict "add a new player" criteria and would still have been blocked.

I quickly closed my sockpuppet PRs and made a new PR (#243) that was obviously testing. I think I wasn't fast enough, though, because before I managed that Todd created a PR (#242) to require users to exist on GitHub for checks to pass. I haven't asked him what he was thinking, but my guess is he saw my PRs and thought I was testing the system, as opposed to trying to win with sockpuppets.

He extended #242 to fix the "can't actually join" bug and to require join PRs to be authored by the person trying to join, but then I ran into another problem. I made another puppet, nomic-user, and had them create #244. If you click on that, though, you'll get a 404. It turns out that PRs created by flagged users aren't visible to anyone else. Which means I would need 2N-1 unflagged sockpuppets to win.

That's not too bad, the flag notice just says to contact support to get the account unflagged. But then I thought before I did that I should look in the terms of service, and unfortunately that has "you may not have more than one free Account". Violating GitHub's TOS is not in bounds, and using paid accounts to win isn't fun, so we decided to ban sockpuppets.

At this point it feels like the game is winding down, with Pavel leaving and me starting to lose interest. Even though I couldn't turn puppetry into a win it was still a lot of fun!

full post...

Bathroom Construction: Framing

I've been working on redoing our bathroom (plans) and after I finished the demolition (details) it was clear that I couldn't just put a new bathroom on top of the old framing. Not only were the original joists in terrible shape, but someone had removed a section of load bearing wall.

I brought in a structural engineer, the same one that did the work for our dormers, and he said we needed a header and two columns down to the basement:

The header needed to go where the load bearing wall used to be, to support the four joists that had been coerced into running the full width of the house. It would sit on two columns, a wall-side one landing on the central beam, and a chimney-side one with a new footing.

Figuring out exactly where these columns would run was pretty hard: the area that they run through has a ton of plumbing, electrical, and existing framing. I started with the chimney-side one, which meant digging a footing.

(If you had told me, before I started, that renovating our second floor bathroom would require digging a hole in the basement floor, I would have been pretty surprised.)

Footing

Last time I made a hole in the basement floor, when I put in a sump pump, I rented a jackhammer. The floor is thin enough, though, that this isn't really needed. First I scored around the edge with a brick chisel:

Then I gave the center some good blows with a sledge hammer:

Then it was just a lot of shoveling. This is a time of year when the local water table is just below our basement floor, so the bottom of the hole got a bit of water in it. I pumped it out as I went, and it didn't fill quickly. I took a photo with a yardstick that I can show to the building inspector if they want to verify I made the footing deep enough.

I filled the bottom of the hole with gravel:

Then I mixed bags of standard concrete and poured them in. One bag at a time, over and over. Something like 400lbs of conrete, plus water. Once it was smooth I put the metal column base in, with a plumb bob to line it up with the hole above.

Chimney-side column

I built the chimney-side column up from the basement. I wanted an ~18 foot column, and there wasn't room to move around with something more than ~7 feet long, so I made it out of staggered 6.5-foot lengths. Each section I screwed together and then put in 16d nails from both sides. It's three 2x6s. Working by myself clamps were a very useful substitute for extra hands.

As I built it up, here's what it looks like from the top, coming up through the mysterious convenient dead space next to the chimney.

The footing was only recently poured and the metal column base needed to not get squashed, so I built up a bit of wood to protect it from the column.

Here's what it looks like done. You can see I used pressure treated 2x6s for the bottom section of the column.

Wall-side column

The first step was to figure out exactly where the column should run. I opened up a bit of the wall in the first floor bathroom to see.

The column couldn't run through that box because the stack was there. It couldn't run left of that box because that would take more of the bathroom and also at the top it would fall on the wrong side of where one of the joists had been cut all the way through. It couldn't run right of that box, through the back of the closet, because then it would fall on the stack (which made a 90° turn just under the floor and ran along the top of the foundation). After talking to the plumber, and considering that our stack was 100-year-old cast iron and near the end of its life, we decided to remove the stack.

Now there was enough space to lower down a 9-foot triple 2x6 column in one piece, and have it sit directly on the end of the central beam.

Header

The bathroom below had a drop ceiling, which meant there was room to run a header between the bottom of the joists and the top of the ceiling.

Before putting in the header I carefully measured the columns and cut them exactly to length. The goal was that the bottom of the header would be just above the drop ceiling, to give as much room as possible to move the header pieces around above.

The header needed to be just over six feet of triple 2x10. While the columns could be built from pieces that didn't run the full height, each 2x10 had to run the full span. Getting this into place was very difficult, and I wouldn't have been able to do it by my self. My dad helped with this part (thanks Rick!)

There were 2x3s running horizontally, perpendicular to the joists, and while they weren't intended to be structural I was pretty sure they had fallen into that role. So I didn't want to cut any we didn't have to until we were done with the refit. We figured out how to cut just one section of one of them, and fed the 2x10s one by one through the gap.

Rotating the 2x10s, first horizontally and then vertically, was an extremely tight fit. This was very difficult, and involved some carefully targeted additional demolition before they would make the turn. This took a long time!

There was also a vertical 2x3 that they had used as part of boxing in the stack which was in the way of where the header would need to run. Unfortunately it looked like it was probably holding up about one joist's worth of the floor weight! Before we could remove it we needed a temporary support. We ran another 2x6 from the central beam in the basement to just this joist, and hammered it into place to take the load. Once I cut the 2x3 it was very clear that the 2x6 was carrying a lot of weight.

We were finally able to get the header fully in place, and sitting on the column caps, which aren't yet bolted on.

Bolting on the caps was slow going because it was such a confined space. No room for the drill, so I needed to use a ratchet. It's possible I could have done it with a right-angle adapter; I've gotten one to try the next time this comes up.

Here's what the header looks like in place:

The top of the header was an inconsistent distance below the joists, so I needed to shim it up. Over a few days I brought the center section up by about 3/8", one eighth at a time. The goal wasn't to make the floor level, but to makde sure the load was fully on the new header.

Sistering

Nathan came over and helped me sister the joists. It would have been possible to do alone, but much more work. The engineer had said I could use single 2x8s or double 2x6s, and since I didn't want to raise the floor I went with the 2x6s.

From the wall to the header was just under thirteen feet and I had bought fourteen-footers. We decided not to cut them, since they'd fit into place just as they were. We worked from the chimney side over, being very thoughtful about when to cut crosspieces and when to remove existing inadequate sistering. Having someone to talk this through with was another substantial benefit of working with someone else.

Several joists had been cut all the way through, some of them in multiple places. Most, but not all, of these cuts had been sistered with about 3' of 2x6 as a sandwich, which is way too short. We sandwiched all of them for their whole length.

Here's what it looks like with some masking tape on it to represent where we were considering putting fixtures, walls, and doors:

Blocking

The next day I put full-height blocking between the joists so they wouldn't be able to rotate. I also connected the blocking to the header, so the joists wouldn't just be sitting on the header.

Door

When I was doing the demo I cut a very rough opening where the door would go in order to bring demolition debris out. The joists on either side of that had an inside dimension of 29", which was just a little too tight. I considered skipping the jack studs and using header hangers, and even bought the header hangers, but then decided to just reframe it all. Initially we had:

I took out the window and supported the inside of the window with new short studs. Then I doubled up the king stud on the right of the door, and put in double king studs on the left as well. Each time I cut them very slightly long and hammered them into place to make sure they were taking the load. I removed the stud on the left of the rough opening, made a header out of double 2x6s with a 1/2" spacer, and put that in place. Then I put jack studs underneath. A nice new framed opening:

Next steps

Now I need to get this inspected, and it's possible there will be things that need fixing. Then it's time for insulation, rough plumbing and electrical, subfloor, framing the partition wall, etc.

full post...

Nomic Game 3

Our third game of nomic ended quickly, before all of the players had even managed to join (#107). While trying to fall asleep last night I realized a way I could win: #33 gives a point per PR merged, and #49 allows transferring points between players. To keep someone from gaining unbounded points from transfers, #49 requires the total number of points to decrease. This also allows you to make PRs that reduce your points without anyone else having to approve, which is how I could have won last game (#103).

So what I realized I could do was create PRs like #112 that all consisted simply of adding the file players/jeffkaufman/bonuses/lose-a-point with contents -1. All of these PRs would be allowed to merge, but then the file would only be created once, and if I merged N pull requests I would expect to gain N-1 points. The key thing is that git does not consider it a merge conflict if two different PRs create the same file with the same contents.

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Nomic Game 2: Another Conclusion

This morning Chelsea won our second game of Nomic with a timing attack:

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Nomic Report III: Conclusion

The Nomic game has ended, with David (dchudz) the winner:

Since the last update a week and a half ago we made some good progress:

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Simultaneous Shortage and Oversupply

Here are two things I wouldn't expect to be true at the same time:
  • The EA movement has a ton of programmers, many of them earning to give, and many of them interested in moving into some form of direct work.

  • Roles for programmers in direct work tend to sit open for a long time, and people trying to hire programmers have a really hard time finding people.

As far as I can tell, though, these really are both true!

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