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That's brilliant.

What about using a laser to destroy the weeds?

I suspect this would result in rather superficial weed destruction, since the roots underground would be unharmed and would cause the weed to regrow a few days later. Unrooting the weeds definitely sounds more reliable to me.

> Unrooting the weeds definitely sounds more reliable to me.

The robot in the article just pushed the weed underground a few inches. I imagine that some weeds would just pop back after a week, and that the robot would just punch them down again.

So you now you have to run your fleet of robot weeders over the field twice? That seems like a waste of time and $ when you could achieve the desired result in a single pass. every extra pass is also more soil compaction.

Pushing the weeds below the surface is probably less disruptive to the surrounding crops than tearing out the roots. And since you have to run the machine constantly anyway to prevent new weeds from establishing themselves, just poking them down repeatedly will eventually starve them of sunlight and kill them, or at least prevent them from ever growing large enough to cause a problem.

You would already need to run the weeder every few days to catch future weeds. Much of it would be about disrupting the weeds while crops get established.

If you run the robot every week, burning off the stem & leaves, the plant will eventually starve.

Around here, we have an invasive species called scotch broom. If you cut off the plant at ground level, it will grow back. But if you cut it off after it flowers, it'll die. Mowing it flat regularly will also kill it.

On the other hand, with a laser you could process huge areas at extreme speeds. Think 100 zaps a second.

> Think 100 zaps a second.

At very low power, not enough power to kill a plant that has lots of water in it.

Why do you assume low power? :)

While you're at it, attach it into a drone. Useful for animal herding and crowd control as well.

> Why do you assume low power? :)

Because outside of a lab, lasers with enough power to zap and destroy 100 plants per second don't actually exist?

(Not that I've done the math, but you really do need a lot of power.)

There are several technologies in startups that can kill weeds using custom levels/frequencies of light - it takes about 3 seconds per spot to kill a weed.

Lasers, especially fast ones will only handle superficial stuff.

This video of punching the weeds looks promising, but just a thought: maybe you could focus sunlight to burn them? :)

While it would be much more energy-efficient, such a process is bound to have a very low rate of weeds destroyed / minute.

It's a field, you have time. Also, maybe that means you need more of those robots? :).

Microwaves and lasers:


Fire risk?

I don't like this one bit. I've cancelled my Prime membership on principle...

I have some way to go, but gradually I'm working to stop giving energy to organisations that don't align with my values... even if it makes my life marginally less convenient.


I was sorry to read this.

From my perspective, this comment broadly captures what is so tragic for me about his situation and the potential pitfalls of isolation-by-riches: the apparent fact that the majority of people discount a wealthy man's cry for help (read "willingness to be vulnerable"), dehumanising him and robbing him of an opportunity to heal - whether through therapy, community, or some other significant life change.


They do that because they measure the rich person's woes and find that they are considerably less than theirs, its basically that they don't appreciate the person in the sedan chair complaining about the heat.

A wealthy person is still a person, but when another looks at their burden and finds it lighter than their own, they often don't pity them because they perceive they can much more easily mobilize their own help (see: an article about a billionaire's emotional state vs European immigration crisis.)

Basically, the "pitfall" of isolation by riches is a problem a large portion of humans would like to have.


Nobody is robbing Notch of his opportunity to heal. We as internet commentators can't do that. We're not really dehumanizing him, either-- just pointing out that his burden is light relative to most.

If you're having trouble carrying a light weight, sure, get help. It just seems pretty childish to complain to an open microphone about a something so petty. I have no doubt these emotions are very tough for Notch, and I see that I would probably have the same problems in his situation.

But seriously, this isn't the kind of thing you say to a wide audience without being completely out of touch. He should know better.


> just pointing out that his burden is light relative to most.

Yeah, and as someone who makes enough money to not worry about not being on the streets, but also not enough to be able to just do anything I want, my burden is light relative to people in 3rd world countries.

No matter what you say, someone's burden is light compared to another, and completely denying someone like Notch the right to be able to get their burden off their chest, just because their's is less than yours, is asinine.


You wouldn't complain to someone who couldn't afford to eat that you couldn't afford a Ferrari, right?

Same principle applies here...


When Open Exchange Rates [0] began making decent returns - not a $2.5billion exit trajectory by any means, but certainly enough to set me apart from my peers - I felt I was on the path to something great. I thought something like "Now that I don't need to trade my time for money, I'll be [popular, happy, fulfilled, 'enough']... and I'll grow automatically."

I awoke years later (thankfully only two) to find that I had none of what it would take to be happy, or to grow as a man, and a seeming eternity of free time stretching out before me to enjoy my comfortable isolation.

I only had to taste the false freedom of wealth - really just an appetiser - to know that no amount of resources would fulfil me if I could not meet basic emotional needs, go through pain and challenge, be vulnerable, build relationships, and self-nurture. God forbid I ever come into the kind of money he has - but if I do, I pray I would have the courage to start from scratch to build the life that nourishes my spirit.

I think many will take a high position, point a finger at this man, and feel good about themselves. It's easy to look at him and say "High value problems," and "He has nothing to complain about," or even "He should be X/do Y...", etc. The real tragedy for me is that his issue can be so socially unacceptable.

I rate him for being open and vulnerable about this part of the journey and hope he finds the peace he deserves.

[0] https://openexchangerates.org


I clean my living space, clear out old baggage and remnants of old identities, to make space for the new. Lethargy seems to come when I am ready to let go even more and allow life to show me my next steps, but I need to listen to the message.

In the depression/anxiety/lethargy space I find it's not time for any major life breakthroughs.

The biggest breakthrough for me is finding the initial half ounce of mojo to begin the space-clearing and space-claiming process... whether washing a single dish, throwing an old piece of clothing, deleting an email I'll never get around to replying to.

Then, doing it again, and again, one damn t-shirt at a time.

Soon the momentum picks up and the clearing happens by itself.

Also, for me generally the only way out is through - I find it starts with acceptance of this moment as it is, so I'm careful to not add my judgments ("This should not be happening", "I fucked up", etc.) to the situation, but instead hold the lethargic/anxious/depressed parts of me in kindness. Not trying to change anything about them.

From that starting place of self-kindness I can take a breath, dust myself off, and begin taking one simple, tiny action – not to make anything happen but only to make space for the new and invite it in.

I ask myself often: Which old junk am I ready to let go of to make space for the new? I don't need to know what the new is, just trust life and start throwing away the shitty t-shirts.


+1 for cleaning. Really helps me when I get into a slump. Something mindless, but productive with clear results. Lets my mind process whatever it is that is slowing me down.


I created Open Exchange Rates[0] as an open source project four years ago, publishing free currency data into a GitHub repository.

It was launched alongside money.js[1] (a minimal JavaScript currency conversion library), designed to work seamlessly together and both found a brilliant response and grew an organic community.

Hundreds of tutorials and thousands of posts and mentions later, GitHub eventually contacted me and politely asked me to take down the exchange rates repository, because they were being hammered by people requesting the data - only at this point did it occur to me that I'd created something of genuine value, and (6 months of fretting and tail-chasing later) I opened up a paid option.

For me the key thing was: I never intended to create a business. It was (and is) a labour of love. We've since grown to be the industry-leader for our area - "good enough data" for the startup and SME market - and count Etsy, KickStarter, WordPress and Lonely Planet among our clients.

Although it's no longer truly open source, 98% of our users are still on the Free plan, which will very soon be expanding to include all features (so, no more limiting by price tiers) - this is how I still feel so passionate about it.

I can't wait to publish the next steps in our journey - where we're opening everything up to the community and marketplace. I don't like where the industry is heading (competitive, closed, secretive) and we've chosen to move towards transparency and sharing.

I like businesses built on a core of open source community, because they're in service to the people who are actually building the products, rather than those in the traditional 'upper levels'. This means there's really no "sales process" (which I'm massively allergic to) - apart from the occasional grilling from the accounting department, who may find it hard to trust a business based on open source principles.

Good luck!

[0] https://openexchangerates.org

[1] https://github.com/openexchangerates/money.js


Really interested by the pricing on your signup page (https://openexchangerates.org/signup), where you have the prices from most expensive on the left to cheapest on the right. I have mostly seen (and always built) these the opposite way around. Is there a particular reason why you did this? Did you A/B test it?


I've done this before. When I did it it was a conscious design decision to use price framing[1], so the site has a very expensive product, two mid-priced products, and a free product. It's nice when the very expensive product sells, but it's mostly there to make the two non-free products look like reasonable purchases.

I haven't A/B tested it, that's something I should do.



Awesome idea. Would be great to see some test results, once you test it.


I'll try to remember to test, then I'll try to remember to post results ;)

It'll also be interesting to see drop-off at that point in the funnel - my signup form is a bit of a monster.


Good question. Never A/B tested (!) but there was some intuition about leading with the most expensive option. Perhaps to make the others seem more reasonable in comparison.

In any case, we're changing this very soon to list from left to right including the Free plan in the table (I don't like that it's hidden beneath the paid options).


I'd like to thank you for creating your API, and for the generous terms on the free plan. I'm using your API to estimate my weekly revenue (internal reporting).

A suggestion: It would be awesome if it was possible to download historic data in batch format (eg. CSV) which would make it easy to copy the data into my reporting database. When I started working on my own reporting solution, I'd have paid $100 just to download a CSV file with 5 years of exchange rates, even though the data is available for free on a bunch of websites, since it's such a hassle to collect.


The Bank of Canada have downloads (CSV, RSS) for historical rates http://www.bankofcanada.ca/rates/exchange/ - you may need to convert to eg USD rates but the data is easily accessible.


Thanks and you're welcome! We do have a time-series bulk download, but it's still in JSON format and currently limited to 1 month of data. This will be redesigned soon and looking to include CSV downloads as an option.



We do have a time-series bulk download, but it's still in JSON format and currently limited to 1 month of data. This will be redesigned soon and looking to include CSV downloads as an option.


Github asked you to take down a hosted repo because it was too popular? I'm slightly shocked at that (just a tiny bit)


It isn't shocking at all in this context - GitHub is for hosting code (and other code-like things), it isn't a content delivery network.


I would guess because Github was not being used as a code repo, but was essentially being used as free CDN for the data file. I've seen direct linking to Github raw files like that before and wondered if it was something they condone.


Yep. GitHub were cool about it, explained that some people were making thousands of requests per second for no reason at all and it was impacting others users on the network. It's not the intended use of GitHub at all and I genuinely had no idea it would become popular.


Are your top customers really only paying you $97/month? Seems like you could charge them substantially more money.


Isn't that stretching it a bit too much? It's a service that can be replicated for free with the Yahoo! Finance APIs and a couple hours of your time.


Yahoo finance APIs are notoriously finicky. They go down. They change. Hard to build a business off that.


I can't say I can relate, I've been using them for two years without an issue.


Great Saas , can you tell from where you poll the currency data ?


Wow, I was looking for something like your project for months!



Location: London, remote possible.

Timeframe: ASAP, 3-6 months.

We’re looking for a software developer for a large contract at Open Exchange Rates, the fastest-growing global currency data API on the web.

You’ll need thorough knowledge and experience building API stacks and environments, including nodeJS a plus. You’ll need to be creatively independent – able to architect, implement and document expertly – and able to confidently lead a project from start to finish.

All the other usual keywords apply (though for this stage, advanced front-end skills not required).

We look forward to hearing from you.

JOBS at openexchangerates.org



We're looking for a creative branding artist and graphic designer at Open Exchange Rates.

This will be a well-scoped and fast-paced contract, with ongoing work for the right candidate.

We need:

. Diverse and in-depth experience with branding and design in startups, software-as-a-service and larger companies both B2B and B2C,

. Knowledge and understanding of the open source and web development community,

. Strong communication, accountability and authenticity,

. Skill with creative writing and storytelling,

. Fluent written and spoken English - we'll be Skyping and Slacking a lot – and

. A calm, confident, creative, collaborative approach.

If this sounds like you, please email JOBS at openexchangerates.org, including:

. Your portfolio

. Your availability

. Your daily/weekly/per project rates



We're looking for a freelance JavaScript developer and open source advocate at Open Exchange Rates, to take over maintenance of our two popular open source libraries, money.js[1] and accounting.js[2].

Between them, these projects have hundreds of thousands of users, thousands of articles and tutorials, and hundreds of community forks.

This is an opportunity to get paid to chill out with a passion project, which carries your name and belongs to the developer community forever.

You’ll be taking ownership of:

* keeping the libraries in alignment with the latest coding standards,

* merging contributions and resolving issues from the GitHub community,

* keeping track of forks and integrations,

* rewriting their documentation, and

* leading and interacting with the community of developers building with them every day.

NOTE: These projects are public and open source, but we're treating this as a standard freelance project to begin with. After the first phase, we'll have a discussion to see how things want to progress. We have many more open source projects in the pipeline – and internal gigs too.

We’re from London, but you can be anywhere. Let's make some art.

Please include your GitHub profile, website, relevant projects and experience, and availability over the next 6 months.

CONTACT: Jobs at openexchangerates.org

[1] http://openexchangerates.github.io/money.js/

[2] http://openexchangerates.github.io/accounting.js/


SEEKING FREELANCER: Finance-industry startup seeks data scientist for ongoing part-time lead role.

We’re looking for an engineer with a finance background (or a finance person with an engineering background!) to help out behind the scenes at Open Exchange Rates.

Open Exchange Rates[0] is the fastest-growing currency data API on the web, loved by the likes of Etsy, Shopify, Kickstarter and thousands more.

We have a super-exciting backend engineering project involving overhauling a large part of our platform, over which you'll have complete autonomy within the requirements.

Project scope, budget and timeframe are all negotiable for the right contractor, but likely to be 2-3 months, plus ongoing work available.



* Python, client-side and server-side JavaScript (+PHP and PhantomJS a bonus); intermediate sysadmin skills

* Proficiency with relational and non-relational databases

* Understanding of foreign exchange markets

* Designing and implementing algorithms for financial data analysis

* Understanding of APIs, methods of online data collection, and authorisation mechanisms

* Ideally: Expert front-end development skills in HTML/CSS/JS (negotiable in project scope)

* Remote possible; UK preferred; London ideal.

* Chutzpah



Get in touch with josscrowcroft@gmail, with a little about yourself, your work, your story and what makes you come alive. Relevant experience also appreciated.

[0] https://openexchangerates.org



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