Weeks are better than months

If I say to you “let’s meet in a month” you probably won’t know exactly when we are meeting again. It’s an approximation at best. Do I mean 30 days? do I mean the exact same day number but on the next month? What if that month doesn’t have that day, like February 30th? What if we are in a business setting and 30-days-later or same-number-of-the-month falls on a Saturday? As you see, months, as a measure of time, can be pretty useless. Specially when talking about small numbers, like 1 or 2.

There’s a better unit. The week. How long is the week? 7 days. All weeks are 7 days, no exceptions. If I say “‘let’s meet in a week” you know what I mean. Add seven days to today and that’s when we are meeting. If it’s a Monday, in a week, it’s also a Monday. Also, weeks are smaller, more granular, which is useful for little projects. If I ask “When is X is going to be done?” I’d rather hear it expressed in weeks rather than months.

We normally use months because they allow us to set up a time in the year. We can say “July” and know when it’s that. Weeks can do that too actually.

Did you know that the weeks of the year are numbered? It is call “ISO week date” where ISO stands for International Organization for Standardization. Since a year doesn’t start on the same day of the week every year and also has variable numbers of days, years may have 52 or 53 weeks. This allows to say week 5 or week 30 and refer to a specific week of the year. There’s even a format: 2015-W5-1. That referees to Monday of week 5 of 2015.

If you are using Google calendar, you can add the week numbers to it following this procedure:

  1. Click on “Other calendars”
  2. Click on “Browse Interesting Calendars”
    Using Week Numbers in Google Calendar - Browse Interesting Calendars
  3. Click on “More”
    Using Week Numbers in Google Calendar - More
  4. Next to “Week Numbers” click on “Subscribe”

From now on, in your week view, you’ll see a small rectangle with the week number, in this case, week 6:

Using Week Numbers in Google Calendar - Week 6

It also appears on your list of other calendars, so you can change the color and enable or disable it:

Using Week Numbers in Google Calendar - Other calendars

The most organized businesses I came in contact with, made extensive use of calendar numbers and I intend on doing the same and recommend it to other people. I think the first obstacle to overcome is making the number ubiquitous so that when you use it, saying “week 6” for example, people know intuitively what you are talking about.

Let’s do it.

Picture by Yandle.



2016-01-01 16.47.48

LEGO-powered multi-party-popper deployer

On New Year’s day, my partners woke me up to the sound of “Happy New Year” and two party poppers going off. Then, they made the mistake of falling asleep on my bed. Revenge came, powered by LEGO, let me introduce you to The LEGO-powered multi-party-popper deployer:

2016-01-01 16.47.482016-01-01 16.47.33

So, it actually didn’t work quite well, when I pulled it disassembled and three party poppers didn’t deploy. If you are building one, make sure to add more reinforcements.


Happy New Year

Happy New Year! Up to now, Marty McFly has showed us what to expect, but from now on, we are in uncharted territory. It’s time to start making our own future, our own decisions. We can now focus on things more important than hoverboards. Just kidding, hoverboards are cool.

More than four years ago I co-founded Carousel Apps and since then I’ve been the CTO and now I am the CEO. I, like many geeks and entrepreneurs, can super focus on one thing and ignore all others. This can be very productive, but it can isolate you.

For example, I forgot how much I enjoy sitting down with someone and being the bounce board for their ideas or providing my technical expertise on how to execute those ideas. I ended up doing just this recently, which was a reminder, and now I want to do it more often. During 2016, I want to do it once a week.

I’ve been coding for 25 years, I used around 17 different language in many different operating systems and countless frameworks. I worked for Google. I co-founded two startups (or more, depending how you count). I had production systems in both Linux and Windows. I use a Mac and I used Linux as my desktop. I’m the CEO of a distributed company. If any of these things or the many others I’ve done make it sounds like it would be useful for us to sit down for an evening and talk about your startup, let’s do it!

During 2016 I want to spend one evening a week helping a different entrepreneur each time, specially non technical ones, with their issues, specially the technical ones. I want to do this for free, just because it’s fun. I’m located in London and I want to divide my time roughly equally between face to face meetings in London and remote ones with people from all over the world. By the end of 2016, I hoped to have helped 26 London based entrepreneurs and 26 from other places.

If this is something that you want, fire an email to pupeno@pupeno.com and tell me a bit about yourself and what do you want to talk about.

Happy New Year!


to-jdbc-uri 0.5.0 released

We just released to-jdbc-uri 0.5.0 with support for URL parameters. Courtesy of Joe Kutner.

I’d like to note, sometimes I hear that the Clojure community doesn’t care about testing, but to-jdbc-uri has a very complete testing suite and so far, this and other contributions came fully tested.


How I found one of the earliest browsers in history

Yesterday, the web celebrated its 25th birthday and to join in, I want a little story. A couple of years ago I found a NeXTcube. I’m not going to say where it is to avoid vandalism (the computer is publicly accessible under some circumstances without much oversight), but this is the story. Sir Tim Berners-Lee coded the earliest version of the web in his NeXTcube workstation when he was working at CERN, so, I was always interested in this machines, from a historical/playful point of view.

The cube that was in front of me was more or less abandoned and I asked the owner if I could play with it. He was very reticent but I was more relentless and I got to play with it. He told me that Next computer belonged, at one point, to CERN and that it has not been used since then. I decided to explore it.

The first interesting thing I found was a file containing a lot of email addresses from people that seemed to work at CERN or be related to CERN in some form or fashion. The owner of the computer decided to be overly professional and deleted the file.

The second interesting thing I found completely blew my mind. There was a folder called WorldWideWeb and inside it several files called WorldWideWeb_0.1.0.tar, 0.1.1.tar, 0.2.0.tar and so on. Could this be? I opened one by one and indeed they were apps. I started with the oldest and executed them one by one.

The first one raised an error as it tried to contact cernvax.cern.ch (this Next cube was disconnected) and then it crashed:


I kept on going and eventually one started. It was very plain but I knew what it was. I quickly went back to my terminal, open vi, and wrote a small HTML file, which then I passed as a parameter to the little WorldWideWeb_0.2. It worked… it displayed an h1 as a title!

I was jumping out of my skin. I don’t want to publish the whole picture to avoid releasing private information, but I’m standing, next to the cube, pointing and what could possible be the earliest version of the web browser that still works today, displaying a web site I just coded (it says Hello World):


Then I discovered the browser allowed me to edit the page, directly there, without having to do anything special, and I remembered that Sir Tim Berners-Lee originally designed the web to be read-write, not read-only.

That was one of the most exciting moments of my life. When I got home I wrote an email to Sir Tim Berners-Lee, telling him of my finding and where he could find that computer, just in case he wanted to get ahold of those binaries (I couldn’t find any source code anywhere on that machine). He never replied, I don’t know if he ever got my email. I bet he gets a lot of it and that he’s a very busy man.

Update: explained a bit why I don’t want to reveal where this happened.


How to legally submit an app to Apple’s App Store when it uses encryption (or how to obtain an ERN)

Disclaimer: I am not a lawyer, this is not legal advice. 

Shameless plug: I am available for hire doing Ruby, Clojure, Python or many of my other skills including managing developers.

There’s a lot of conflicting information out there about whether you need an ERN or not to publish an app in the App Store. I spoke to Apple representatives as well as various employees of a couple of US agencies. As painful as it is, if your app is capable of the simplest, most standard, of encryptions such as SSL/HTTPS then you need to answer your export compliance questions like this:

Mac App Store questions and answers about encryption

The conclusion from selecting the above answers:

To make your app available on the App Store, you must submit a copy of your U.S. Encryption Registration (ERN) approval from the U.S. Bureau of Industry (BIS).

In some places, you’ll see CCATS instead of ERN. I’m not 100% sure, but it seems CCATS was a previous more bureaucratic version of the ERN. Right now, what you need is an ERN and this is our journey to get it. We are publishing as much detail as possible so that you can replicate it for your own application. There are some other blog posts that explain how to do it, but we found that over the years, some of the steps changed and we had to find a new path. Since this is going to happen again, we are adding as much information as possible so that should your path be slightly different, you won’t have much trouble finding your way through it.

Starting at the beginning

After being utterly confused by both Apple’s as well as BIS’ FAQ and how to pages, I decided to go the homepage for the Bureau of Industry and Security and see where it took me:

Homepage for the Bureau of Industry and Security

At this point I new SNAP-R was relevant to my needs. I was almost under the impression of needing one, even though I didn’t know what it was. Going through that page I found this:

BIS Would you like to

Yes! I’d like to submit an application (SNAP-R) – fourth item in the list. That takes you to this page: http://www.bis.doc.gov/index.php/licensing/simplified-network-application-process-redesign-snap-r, which defines what a SNAP-R is. It stands for Simplified Network Application Process – Redesign. I think a SNAP-R is sort of an account with the BIS. There’s no mention of ERN in that page, but it says:

You must have a Company Identification Number (CIN) and an active user account to access SNAP-R. The procedures and requirements for obtaining a CIN and user account are set forth below.

You need to obtain a CIN before you can proceed. If you scroll all the way to the bottom of the page, you’ll see:

BIS Obtaining a CIN for a SNAP-R for an ERN

And that link, ladies and gentlemen, is the most promising I’ve seen so far. It takes you to https://snapr.bis.doc.gov/registration/Register.do which looks like this:

BIS SNAP-R Company Registration for an ERN

The SNAP-R Company Registration process

After completing and submitting that form you’ll get an email to confirm your email address. I recommend limiting yourself to ASCII characters here, as the é and á in my name got mangled. That email took only a few minutes to arrive but the confirmation page claims the next step might take up to five days:

BIS SNAP-R Email confirmation

Some people claim to have been finished in 30 minutes or even less. I suppose it depends where you or your company is located. In my case, the five days elapsed so I sent them an email and two days later I got a reply telling me to call their support number: +1-202-482-2227 (later on I learned that another phone number that might help is +1-202-482-0707). When I talked to a representative, he said that I should have received the activation email already and just re-triggered it. Maybe calling them after a couple of days would have been a good approach to speed things up. Shortly after my call I got this email:

BIS SNAP-R Account Invitation email - for ERN

That link takes you to a page to set up your log in and password:

BIS SNAP-R Login ID and Password Setup

After entering those details, voila! you have an account:

BIS SNAP-R Login ID and Password Setup - account created

You may now log in:

BIS SNAP-R login in - for ERN

After logging in, you are now in your SNAP-R Home page:

Creating a new work item within your SNAP-R account

The next step is to create a new work item, which you can do from the sidebar. That takes you to a page that looks like this:

BIS SNAP-R Create Work Item

The type of work item that you want, to be able to distribute apps with encryption, is an Encryption Registration:

BIS SNAP-R Create Work Item Type Encryption Registration

Now, about the Reference Number, the question mark next to it sends you to https://snapr.bis.doc.gov/snapr/docs/fieldHelp.html#NewWrkItem1 where it says:

Enter a valid reference number for the Work Item. Reference numbers must be in the format “AAA1111”.

which didn’t really answer what a reference number is. I decided to call them again and when I asked the question they put me on hold for 25 minutes. I hung up, called them again and I was speaking with someone else in less than 3 minutes and she answered. The reference number is just something you make up, for yourself. It’s not something you obtain and it seems as long as you follow their convention, it’s fine:

BIS SNAP-R - Create Work Item - Encryption Registration and reference number

After creating the work item, you are invited to edit it. It starts partially populated and it’s straight forward:

BIS SNAP-R Edit Work Item Encryption Registration

Well, it’s straightforward until the last part: Documents. You need to attach the Encryption Registration Supplement No. 5 to Part 742.

Creating the Encryption Registration Supplement

Creating the supplement, thankfully, is easier than it looks; that is, when you know what you have to do. There’s a document number 742 that you can download from https://www.bis.doc.gov/index.php/forms-documents/doc_download/1208-742 and  on page 60 it has the Supplement No. 5: Encryption Registration. These are the contents of that page:


Certain classification requests and self-classification reports for encryption items must be supported by an encryption registration, i.e., the information as described in this Supplement, submitted as a support documentation attachment to an application in accordance with the procedures described in §§ 740.17(b), 740.17(d), 742.15(b), 748.1, 748.3 and Supplement No. 2 to part 748 of the EAR.

(1) Point of Contact Information

(a) Contact Person

(b) Telephone Number

(c) Fax Number

(d) E-mail address

(e) Mailing Address

(2) Company Overview (approximately 100 words).

(3) Identify which of the following categories apply to your companys technology/families of products:

(a) Wireless

(i) 3G cellular

(ii) 4G cellular/WiMax/LTE

(iii) Short-range wireless / WLAN

(iv) Satellite

(v) Radios

(vi) Mobile communications, n.e.s.

(b) Mobile applications

(c) Computing platforms

(d) Multimedia over IP

(e) Trusted computing

(f) Network infrastructure

(g) Link layer encryption

(h) Smartcards or other identity management

(i) Computer or network forensics

(j) Software

(i) Operating systems

(ii) Applications

(k) Toolkits / ASICs / components

(l) Information security including secure storage

(m) Gaming

(n) Cryptanalytic tools

(o) “Open cryptographic interface” (or other support for user-supplied or non-standard cryptography)

(p) Other (identify any not listed above)

(q) Not Applicable (Not a producer of encryption or information technology items)

(4) Describe whether the products incorporate or use proprietary, unpublished or non-standard cryptographic functionality, including encryption algorithms or protocols that have not been adopted or approved by a duly recognized international standards body. (If unsure, please explain)

(5) Will your company be exporting “encryption source code”?

(6) Do the products incorporate encryption components produced or furnished by non-U.S. sources or vendors? (If unsure, please explain)

(7) With respect to your companys encryption products, are any of them manufactured outside the United States? If yes, provide manufacturing locations. (Insert “not applicable”, if you are not the principal producer of encryption products)

All you have to do is create a PDF file answering these questions for your application and upload it. I couldn’t find this information anywhere so I called them once again and that’s how I learned that all matters related to encryption were handled by the department… never mind the name, the phone number is +1-202-482-0707. Next time I’m calling them directly – there was no wait, no menu, just a person picking up the phone.

I created a document for my case saying:

Screensaver Ninja Encryption Registration Supplement No. 5 to Part 742

(1) Point of Contact Information

(a) José Pablo Fernández Silva



(d) pupeno@carouselapps.com

(e) 20-22 Wenlock Road, London, N1 7GU, United Kingdom

(2) Carousel Apps is a small London based company producing software apps such as Screensaver Ninja. Our main use of encryption (and so far all of it) is the standard SSL (https), OpenSSH, etc. You can learn more about us at https://CarouselApps.com

(3) We produce

(j) Software

(ii) Applications

(4) Our products use standard off the shelf encryption libraries and tools, such as https (SSL). We don’t develop or intend to develop any proprietary encryption mechanisms

(5) We don’t plan on exporting “encryption source code”.

(6) Screensaver Ninja uses Apple’s Safari component that allows https encrypted communication. This is provided by Apple. I understand that Apple uses OpenSSL which is an open source project and thus may have contributions from all around the world.

(7) We produce software, so, no manufacturing process are involved. All our software is produced outside the United States. The reason for this application is to distributed an app through Apple’s App store.

I cannot vouch for this content, I’m not sure this is the appropriate file to submit, this is only what I did. The next step is to click on “View and Manage Supporting Documents” which will take you to a page that looks like this:

BIS SNAP-R Document Management Encryption Registration Supplement No. 5 to Part 742

There, click “Upload Supporting Document” and you’ll be greeted by this form:

BIS SNAP-R Upload document for Encryption Registration Supplement No. 5 to Part 742

I just came up with a title and keywords, entered the current date and my name as author. I think the only really important field is the document type:

BIS SNAP-R Upload document for Encryption Registration Supplement No. 5 to Part 742 f

Submitting the ERN

With that document in place and attached, we seem to have passed some sort of automatic verification procedure.

BIS SNAP-R Encryption Registration All party addresses have passed verification

I clicked on “Preview Work Item to Submit” and I was given a last chance to look at the application and verify its correctness:

BIS SNAP-R ERN Application with document

The submission process, triggered by the “Submit” button of course, asks you for your name, in a special format, one more time:

BIS SNAP-R Encryption Registration Submit Work Item

And we you click “Submit Work Item” you are done:

BIS SNAP-R Encryption Registration Submitted - Thank you

Uploading Encryption Registration to Apple

I almost immediately got a message in the SNAP-R website:

Screen Shot 2015-11-19 at 10.36.00

And the message was the acceptance of the application including the ERN code (blacked out):

BIS SNAP-R Encryption Registration Accepted

That is the document you need to upload to Apple. Take a screenshot of that page and save it for your records. Back at Apple’s iTunes connect, when you answer the questions stating that you use encryption, you get an upload box for the document:

iTunes Connect Encryption upload ERN

If the upload button doesn’t appear, this is what an Apple representative suggested: “If you do not see the prompt, there could be a glitch in the website. One possible workaround is to change the answer to question 4 to “Yes”. By doing this the upload field should appear.”

Once you upload it, the “Submit” button will become enabled and you are ready to rock. Click it and your app will be on its way to fame and fortune. Well… that is… after they review your export compliance. For now, your app will be “Waiting for Export Compliance”:

iTunes Connect - Waiting for Export Compliance

From Apple’s version statuses, that means: “Your app is reviewed and ready for sale, but your CCATS file is in review with Export Compliance.” CCATS seems to be an older or bigger version of the ERN and in some places we can still find CCATS instead of ERN. Don’t worry, an ERN is all you need if your situation is similar to mine. When the status reaches to “Waiting for Review”:

mac app waiting for review

Congratulations! Your ERN was accepted.  You are done with this bit of bureaucracy.

If this blog post was useful or you find differences in the process, please, let us know in the comment section.

Picture by Yuri Samoilov


Free-form version 0.2.0 released

We are very happy to announce version 0.2.0 of our form building library Free-form. This version includes:

The Bootstrap 3 support means that you can have whole fields defined as succinctly as:

[:free-form/field {:type        :email
                   :key         :email
                   :label       "Email"}]]