<div dir="ltr">Hi Gustavo<div><br></div><div>I'll do a fuller "YouPatch story (tech Geek edition)" hopefully soon, but would prefer to submit to Hacker News a little bit down the track when the site has evolved a bit more, and there's more stuff of general interest for the HN audience. I actually think the most interesting parts of the story are yet to unfold - so stay tuned!</div>
<div><br></div><div>That said, I thought I'd respond here to part of your email here:</div><div><br></div><div>TL;DR: Racket's a great choice for creative, experimental programming, that can also be deployed into production.</div>
<div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
<span style="font-family:arial,sans-serif;font-size:13px">Why are you using Racket, and why is it "better" than C? </span></blockquote><div><br></div><div>I'm using Racket because it's a high-level, productive language, with a really smart and supportive community. I happened to be doing most of my "programming for fun" in Racket when the idea of automating pixel quilt design occurred, so I picked up the nearest tool and gave it a go. That was Racket, and I've hardly looked back.</div>
<div><br></div><div>In the initial, highly experimental, hack / research phase I was pleased to find that the batteries included in Racket were great. Having a REPL makes it possible to do lots of mini-experiments, and out-of-the-box performance tends to be very good compared to more popular, high-level "scripting" languages like Python and Ruby.</div>
<div><br></div><div>Realistically, I might have worked in Python, which I'm also currently fluent in, but the need simply didn't arise.</div><div><br></div><div>Later on, when performance issues arose, with a bit of profiling I was able to identify major bottlenecks, make a few simple optimizations and get "good enough" performance.</div>
<div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><span style="font-family:arial,sans-serif;font-size:13px">Do you hate </span><span style="font-family:arial,sans-serif;font-size:13px">the ugly syntax? Do you implement something very complex that is too </span><span style="font-family:arial,sans-serif;font-size:13px">long to write in C? </span></blockquote>
<div><br></div><div>Why not C? I haven't programmed in C for many years. It's very low-level, and lacks expressive power. The syntax isn't too bad, but real functional programming fits my mind better, and is much faster to develop in.</div>
<div><br></div><div>The last point is key. I learned the lesson that programmer efficiency is often more important than code efficiency around 20 years ago, when I working on my PhD in computational mathematical physics writing numerical black hole simulations -- how times change! -- and switched from writing my simulations in Pascal and then C++ to Mathematica. What happened? Instead of running for minutes, my simulations took hours and I had to run them overnight. BUT, the pace of my research sped up because I was able to develop faster, and better interrogate the results interactively. Since then, computers have got much swifter, so there's even less reason to use low-level languages in application and creative programming, except perhaps in key bottlenecks.</div>
<div> </div><div>* * *</div><div><br></div><div>Now, what I described above mainly referred to the research or "hack" phase, but when it came to commercialisation the technical considerations changed somewhat. </div>
<div><br>
</div><div>I invited John Barham -- who I had previously worked with in a corporate setting -- to join as a co-founder. John is very knowledgeable about web-programming and "the cloud", where my skills and knowledge is far less advanced. I.e., we have complementary and overlapping skills (and get along well).</div>
<div><br></div><div>I had noticed that John's latest web-service, <a href="http://turbohdr.com" target="_blank">turbohdr.com</a>, when you stand back and squint, had structural similarities to what my wife Andi and I had in mind for YouPatch: it's also a cloud-based service in which the user uploads a photo, stuff happens, and you pay to download something. Adding a highly intelligent and capable colleague who had recently worked successfully on a similar project seemed like a good way to complete our founding team.</div>
<div><br></div><div>Anyway, when it came to technology choices, one thing I didn't intend to do was convince John to learn Racket! Similarly, I didn't want to have to learn everything that he knew. In fact, I would have been quite willing to translate key code from Racket into say Python or JavaScript had the need arisen -- say for performance reasons or in order to facilitate collaboration with John -- but we decided to leave the core algorithms in Racket (for image processing and PDF generation) for as long as we could, and they're still in place!</div>
<div><br></div><div>John built most of the rest of the site using mainly JavaScript, Python / Django / Mezzanine CMS served by nginx: a far more conventional stack, and I helped out on the front-end design and implementation.</div>
<div><br></div><div>On the development side I continue to maintain the Racket part and we share the UX / front-end work, and John handles everything in-between. I have further "research" going on in Racket, as time permits.</div>
<div><br></div><div>* * *</div><div><br></div><div>I hope that these notes are of interest to others who might want to try their hand at a start-up. The barriers to entry have never been lower, but that also means there's a lot of competition in the general space. I was heavily involved in an ultimately unsuccessful VC-funded startup from 2005 to 2010, and needed to take a few years out from the scene to recharge and recover. Startups are a huge buzz and great for people with creative and generalist leanings, but also tend to be an emotional roller-coaster.</div>
<div><br></div><div>I recommend using Racket (or some other cutting-edge language) in *your* startup, because you get to make the choices, it may well confer real advantages, it's likely that the community support will be greater than for a more conventional choice, and it can help attract a more passionate, discerning and adventurous class of colleague than going down the path of the conventional.</div>
<div><br></div><div>Dan</div><div class="gmail_extra"><div><br></div>-- <br><div dir="ltr">
<div style="font-family:arial;font-size:small"><b>Daniel Prager</b></div><div style="font-family:arial;font-size:small">Agile/Lean Coaching, Software Development and Leadership<br></div><div style="font-family:arial;font-size:small">
<font color="#999999">Startup: </font><font color="#000000"><a href="http://www.youpatch.com" target="_blank">www.youpatch.com</a></font></div><div style="font-family:arial;font-size:small"><font color="#999999">Twitter:</font> <a href="https://twitter.com/agilejitsu" style="color:rgb(17,85,204)" target="_blank">@agilejitsu</a> </div>
<div style="font-family:arial;font-size:small"><font color="#999999">Blog:</font> <a href="http://agile-jitsu.blogspot.com/" style="color:rgb(17,85,204)" target="_blank">agile-jitsu.blogspot.com</a></div></div>
</div></div>