CEO @yimbymelbourne // Chief @inflectionptswk // Boundless (2027, Hardie Grant) // Emergent Ventures // jonathan@jonobri.com

Melbourne, Victoria
An absolute honour to be on the @FinancialReview Power List. This is a spectacular recognition of all the fantastic work that @yimbymelbourne has done over the past four years. Thank you to everyone who has been part of that.
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Jonathan O'Brien retweeted
I’m liking this trend of the state government stepping in to overrule nimby councils/orgs (see also World Cup Fed Square)
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The Australian Government claims that this constitutes a unique risk. It does not. The same portal that OpenAI is alleged to have scraped has been publicly accessible and independently scraped by members of the public for more than a year. This script was also posted on LinkedIn but it has been subsequently taken down. It fits the bill exactly. github.com/bfiripis/Web-Scra…
Breaking: Anthony Albanese rings up Sam Altman to express "severe concern" after finding out an AI agent hacked into an Australian Medicare data portal in June. Richard Marles says while the impact was "minor" it is a "warning in terms of what can happen" abc.net.au/news/2026-09-24/a…
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Jonathan O'Brien retweeted
I call BS. This was some agent browsing sites and accessed files that were public but not directly linked from main site. They are very carefully calling them "non-public" instead of "secure" or "password protected".
Australia has been hacked. 'And today, I spoke with the CEO of OpenAI, Sam Altman, to express Australia's extreme concern about this incident. And I also expressed my disappointment that it took the company way too long to inform the government what had occurred, and the nature of the way that that notification occurred as well was unacceptable.'
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you're obsessed with the lesbian bar's mask policy because of woke. i'm obsessed with the lesbian bar's mask policy because it reveals the psychotic levels of entitlement bred by stakeholder-veto culture and participatory democracy.
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AI is not that smart. For starters, it hacked the government but failed to lower the mandatory superannuation contribution to 9%
Australia has been hacked. 'And today, I spoke with the CEO of OpenAI, Sam Altman, to express Australia's extreme concern about this incident. And I also expressed my disappointment that it took the company way too long to inform the government what had occurred, and the nature of the way that that notification occurred as well was unacceptable.'
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DeepSeek would have lowered it to 6
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openai crawled a publicly accessible website and the country is freaking out? what?
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can we stop pretending that Strong Towns is a YIMBY organization now?
Strange article from Strong Towns on "filtering". Fundamentally, they do not believe in indirect spillover effects, where adding high-end supply can reduce low-end rents. Instead, we have to intentionally and directly target the low-end. 1/
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Interesting note from e61 modelling out the impacts of the recent tax changes on property investment: only around half of investors actually pay more tax. Big run-up in long term interest rates likely to be a far more substantial factor in recent price falls than tax changes.
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Charles Marohn is fundamentally wrong about how housing markets work and people concerned with housing affordability should stop listening to him.
Replying to @michael_wiebe
This is the crux. Yes, actually, when new apartments absorb demand from young professionals, that does help poor people stay in their homes and it does create more housing options. 5/5
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🚨 At the U20 Mayors Summit, Mamdani Says the Left Has Ceded “Quality of Life,” “Efficiency,” and “Fraud and Waste” to the Right This was one of the more interesting arguments Zohran Mamdani made today at the U20 Mayors Summit, and a reminder that he can be genuinely sharp when he drops the “central casting” routine. “In New York City, there are certain words that have taken on ideological associations.” “Quality of life has come to be seen as somehow a right-wing concern. Efficiency… has been taken on as a right-wing concern, rooting out fraud and waste, a right-wing concern.” Mamdani’s argument is that refusing to engage those issues actually helps the Right. “If you are staring at an example of social disorder or social inefficiency, and the left refuses to explain either why it has happened or how they will fix it, then the right gets to point at someone in the immediate area and say, ‘That’s who did it.’” The harder question is how much of the broader Left is actually prepared to follow the advice.
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An absolute honour to be on the @FinancialReview Power List. This is a spectacular recognition of all the fantastic work that @yimbymelbourne has done over the past four years. Thank you to everyone who has been part of that.
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Building this grassroots organisation into Australia's foremost housing think tank has been the most important work of my life. Thank you, especially, to @hillfolkAU who has been my rock throughout.
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Yarra council at all times for no reason
Canning St, Carlton North and now thanks to Yarra Council you can’t enjoy your wine in the linear park.
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Council really banned a decades-long tradition because some curtain-twitchers complained.
Canning St, Carlton North and now thanks to Yarra Council you can’t enjoy your wine in the linear park.
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Every one of these streets in inner Melbourne needs to be turned into a one way street to create a massive park. Canning is just barely usable parkland as is, but with no traffic on one side it would be a paradise.
Canning St, Carlton North and now thanks to Yarra Council you can’t enjoy your wine in the linear park.
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We call this problem Schroedinger’s Flat.
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Practically nothing about how Sydney builds and manages its housing is a positive lesson for Melbourne. The NSW planning system is a warning for Victorians: things could be much, much worse.
There's almost 100 2-bedroom apartments available for rent for less than $600/wk in and around the Melbourne CBD. In Sydney there are zero. Before giving Melbourne advice on planning and building, the City of Sydney should reflect on its own failures. smh.com.au/national/victoria…
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