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Comment · 3 months ago
I mentioned elsewhere that time taken for setting is also a major factor for why Portland cement is preferred.

Maintenance is probably less of a factor but it also depends on the use case. Take what I have to say with a grain of salt. Lime is a living material that slowly converts lime to limestone. For some use cases, the lime needs to be replenished often through applying lime wash on the plaster of external walls or wet interior walls.

As for load bearing walls or regular interior plaster walls I'm not sure there is much maintenance you can do and they are fairly durable.

As far as I know Portland cement sets faster and is a stronger but has a life span of decades and does not lend itself to be repaired or replenished.

I'd like to also convey some vibes I have about this topic as follows. Imagine having a 2 storey family home made of concrete that you want passed on for many generations. In 50-75 years, repairs/upgrades would require a lot of demolition as concrete with rebar is very strong. Much of the old material is trashed and hard to recycle. A similar house made of lime based products and some stone and wood would lend itself more easily for similar repairs and seamless upgrades and can maintain the same aesthetic look for longer. It feels like lime based products are appropriately strong and suitable for the smaller scale. The old material can be treated like any old dirt or rubble and is less polluting.

Comment · 3 months ago
Sure but lime plaster can be used in bathrooms on the non shower walls as there's no running water but lots of moisture/humidity which leads to mold growth. As far as using it in the grout behind tiles, you may have a point.

I'm considering applying lime wash between the tiles regularly but not sure what the results will be.

Comment · 3 months ago
It is not lime as in the fruit, it is lime as in the material (CaOH2). Lime the material is the binding agent in lime plasters. It is not likely to get washed away.
Comment · 3 months ago
Comment · 3 months ago
You are correct.

I'm not sure why I remember cement to be water proof. Its possible I infered from how its been used around me. I have seen cement very often used where water contact is expected (bathrooms etc). I have also seen brick walls plastered with an extra layer of cement as putty considered to be rain proof and any leaks were thought of as poor workmanship rather than poor material choice.

P.S. I'm not a builder. I've taken an interest in the topic a few months ago.

Comment · 3 months ago
I forgot another important reason why Portland cement is preferred over lime these days. Lime takes a while to set (a few days?), cement sets faster.
Comment · 3 months ago
For those not familiar, the secret ingredients are to do with the Lime Cycle [1]:

1) Quicklime/Slakedlime (Calcium Oxide, CaO)

2) Lime (Calcium Hydroxide, CaOH2)

3) Limestone (Calcium Carbonate, CaCO3)

To keep it simple, typically you start with Quicklime (CaO) and after construction you end up with some mix of all three and after hundreds of years, the masonry transitions to mostly Limestone with microscopic traces of the other two. The slow transition of the lime cycle upon exposure of the masonry to both air and water (rain) ends up making the structure "self healing" and "stronger over time".

Fun fact! Lime putty is anti-mold even in humid conditions because upon exposure to moisture, CaOH2 + H20 becomes too basic for mold to grow on.

Cement/Concrete (based on Portland cement) is water proof but Lime by itself is not. But Roman Concrete, made from Lime and mixing with ash or broken pottery or ceramics makes it water proof [2]. I beleive Roman concrete was used whenever contact with water was expected. Both concrete and Roman concrete have the same underlying chemistry (Pozzolanic reaction) to make them water proof [3].

The fascinating thing is that Lime is everywhere in ancient masonry. Lime is more breathable, workable and sustainable. The only thing is, it requires maintainance, which is why Portland cement has taken over the world.

Modern cement/concrete is amazing for large structures. I hope Lime makes a comeback soon at least partly as putty and for building smaller homes.

[1] https://en.wikipedia.org/wiki/Lime_(material)

[2] https://en.wikipedia.org/wiki/Roman_concrete

[3] https://en.wikipedia.org/wiki/Pozzolanic_activity#Reaction

Comment · 3 months ago
Gotcha and thank you! So the encryption is happening on the OpenAI backend and the agent's clear-text output designated to the sub-agent never reaches local.

Which is a real problem since you can't intercept/monkey patch the ciphertext to decrypt it locally to be able see the clear-text since we don't have the encryption key/algo/salt. No hacking :(

Comment · 3 months ago
Could someone explain to me where exactly the encryption is happening?

I assumed that the main agent makes calls to sub-agents locally. Does Codex work in such a way where the main agent makes calls to sub-agents in the backend (openai server) before reaching local?

Comment · 6 months ago
Out of curiosity, can there not be something like a two party or N party veto? i.e. requiring a minimum of two or N parties to work together to veto?

The choice between just a single party having a veto power vs no party with veto powers seems a little black and white to me. Happy to be enlightened on the matter.

Comment · 7 months ago
I just checked again. 16GB DDR5 (291 Euro) to 32GB (519 Euro). Seems right to me and does not match what you reported. Maybe they updated the website by the time I checked.
Comment · 7 months ago
I checked the prices for 64GB DDR5. There's some variance based on brand/model but the average and trend seems more or less right. Did you happen to notice that it is about prices in the EU?
Comment · 7 months ago
Comment · 7 months ago
Potential reasons I can think of for why they don't disallow name reuse:

a) AWS will need to maintain a database of all historical bucket names to know what to disallow. This is hard per region and even harder globally. Its easier to know what is currently in use rather know what has been used historically.

b) Even if they maintained a database of all historically used bucket names, then the latency to query if something exists in it may be large enough to be annoying during bucket creation process. Knowing AWS, they'll charge you for every 1000 requests for "checking if bucket name exists" :p

c) AWS builds many of its own services on S3 (as indicated in the article) and I can imagine there may be many of their internal services that just rely on existing behaviour i.e. allowing for re-creating the same bucket name.

Comment · 7 months ago
I'd ask politely to refrain from such comments :)

This is not me criticising you. I totally understand the urge to say it. We're all thinking the thing you're thinking of. It takes effort not to give into it ;)

The reason I personally would refrain from making such comments is that they have the potential to end up as highest ranked comment. That would be a shame. Topic of S3 bucketsquatting is rather important and very interesting.

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