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I recently joined early-stage hardware start-up Grow, heading up their software engineering. This is a super exciting opportunity and a chance to work on a technically, very interesting product. What does my role as Head of Software Engineering mean for a hardware start-up? It’s probably going to be mean a lot of things. At a high level, I’ll be the first engineer focusing on the user’s digital experience with this product.

This means I’l focus more on off-device software that will serve as the primary means of user interaction with the device (when they aren’t physically handling it). It’s going to be a mobile-first experience.. so this means building the mobile apps the customer will use.. it also means building the back-end server related components that are needed to support these apps and give us the data we need to get a picture of what’s going on.

It also means I’ll be hiring and building out the future team who will scale this as the company grows!

So, what is this device? Grow is building a outdoor-based automated growing system. What does this mean? The vision is a box that you can plant vegetables in and not have to stay on top of of complex schedule of caring for them. They are watered on a schedule designed for the species and current stage of life of the the plant. There’s an app you use to monitor progress remotely… and let you know about tasks you do need to do such as pruning, harvesting, etc.

Here’s are some pictures of our first prototype.

Grow Prototype - Box & Board

Software wise, there a lot of really interesting problems to solve.

  1. Data retrieval from the bed. If we’re taking care of your plant, we need to pull relatively recent data from it giving us a picture of what’s happening. Soil moisture levels, temperature, etc.. How do we get this data? (Bluetooth, Cellular, Wifi?)
  2. Handling gardens with n number of beds.. i.e. scaling.
  3. Dynamic watering programs. Customizing the behavior of each bed to what is planted in it and it’s needs.
  4. Data capture/analysis of what’s getting grown successfully and funneling this learning back into product/software design.
  5. Early stage validations of hardware components. (Lab testing)
  6. Effective user testing. What do we put in front of users first? What do we need to capture when we do this.
Girl Develop It - iOS Intro Course

Today I am one week into the running/instructing of a 4 week introductory course on iOS and Swift. It’s been such an awesome experience so far planning and executing this course, I wanted to capture the highlights and discuss some of the interesting things I’ve encountered.

What Course?

The course I’m talking about is facilitated through Girl Develop It. The meet-up page is here.

It is meeting for 3 hours on Tuesday nights between 6:30-9:30 for the month of March.


So, full disclosure. I’m a woman. I’m a software engineer. There aren’t that many of us.. proportionally speaking! It’s long been a goal of mine to get more women into this field. I have many opinions on how this can be done. Convincing young girls that it is indeed a career option that makes sense for them is one of these. This, however, is a long game… Hugely important and we will continue to spread this message. But I won’t be coding alongside these individuals for ~10 years. How can I make a quicker impact?

I’ve been trying to find a way over the last 6 months. Early this year I had a discussion with a female colleague of mine who was telling me how she’s really like get into engineering.. specifically iOS app development. I said, that is awesome.. you should totally do it! She mentioned how it’s pretty hard to get off the ground with learning and that she’d really like a course-based setting. We started discussing sources for such courses Girl Develop It, Girls Who Code, etc… But she said they don’t frequently have iOS courses. I thought and said to her ‘I should teach one!’

I contacted Aurelia Moser of Girl Develop It the following week and was on my way to organizing their next iOS Intro course. (The last had been in early 2015.)

My Co-Instructors/Organizers.

As this is a course dedicated to women learning iOS and programming… it should be organized and taught by women right? I found two awesome engineers to help out.

Tamar Nachmany - iOS Engineer at Tumblr
Claire Davis - Recent Flat Iron iOS bootcamp graduate



In organizing likely any introductory course, it’s difficult to draw a line with the amount of programming experience attendees should have. Also, the way Girl Develop It works is attendees sign-up like they would for any meet-up. I had thought if we could screen attendees, we could perhaps offer two courses. One for somewhat experienced coders trying to get into iOS and another for total programming newbies, looking to get into programming via iOS.

As it stands, we decided to just open it up and tell attendees that they should have some (if minimal) programming experience and should understand basic concepts like classes, functions, booleans, etc..

After the course filled up, we sent out a questionnaire to try to get a feeling for who the attendees were and what background they had. It turns out, not surprisingly, that we had gotten a pretty wide range of experience levels. From virtually totally new to programming.. to coming to iOS from a C++ development career.

My conclusion with prerequisites is that if you can’t enforce them, they’re just more of recommendations and you can’t count on everyone to match-up to them. We decided to acknowledge this disparate range in background and to perform frequent check-ins with attendees to make sure they’re getting what they came to get.

Course Structure

Session 1 in action

Lecture vs. Lab

Lectures are boring right? We decided to try to minimize these. With 1 introductory lecture in the first session overviewing the iOS framework as a whole and how it’s really just like any operating system… connecting apps to system resources. Beyond this, we wanted to focus mostly on labs.

Labs are more fluid and dynamic, but can also get bogged down in complexity if you’re not careful. We are trying an approach of doing mini labs.. so we do a little coding (5 min) over projected screen share, then hand it off to the attendees to try the same, with perhaps a slight elaboration.

Project vs. Focused Examples

We were initially playing around with the idea of have a course project where attendees would pick the problem/solution and design and build an app to address it over the course of the project.

We felt this would be powerful because attendees would leave with a real iOS app that they build on their phones at the end of the course. It would also demonstrate the process on a end-to-end.

So, after getting into session planning, we identified that it would be harder and harder to tie the material into everyones different projects. We decided to adjust our approach.

Attendees are being encouraged to still work on an individual project (if they choose) with our support should they need it. In class, we’re going to be doing focused mini projects that will tie together the content being covered in that particular class. This will hopefully ensure that everyone is taking away exactly what we planned.

Course Size

The smaller the better! I had initially thought that the more attendees we can fit the better. Advice I received from other GDI instructors said keep it small.. especially since this is the first course I’m running. In a lab-based class, you apparently should target 4-5 attendees per lab instructor or assistant. This is the number we went with as we’ll have 5 instructors/lab assistants in total.

Moving Forward

In our first session, our coding was fairly limited. We achieved a ‘Hello World’ example and then built a two screen application that would use a few UI elements like labels/buttons to show information and move the user between screens.

For session 2, we had to decide between going further into screen building and UI elements or diving into the Swift language. We’ve decided to go into Swift as using it and understanding it’s strengths will really propel a new iOS developer forward and accelerate overall learning (we believe). We shall see. The intention is to get as much feedback from the course attendees as possible to both frame sessions 3 & 4 but to also hopefully improve this course and offer it again!

Swift - Optionals Mindset

Optionals are one of Swifts most unique features. They are powerful.. but take some getting used to when starting out with swift development. I for one spent about half of my development time figuring out what should and should not be an optional and how and when to pass them around and unwrap them.

There are a lof of posts out there explaining what optionals are and how they work. I want to talk today about how you program with them. Specifically, how you think differently about property, variable and paramter definition as you design your classes and functions (among other contexts).

Thinking Shift

In Objective-C (or other programming languages for that matter).. when working nils you can sort of just pass them around until you reach a case where operating on it with a nil value would cause a problem. At this point.. you check for whether or not it is nil.. and then you perform your operation if it isn’t.

Consider the following class definitions.

@interface Book : NSObject
@property (nonatomic) NSString *name;
@property (nonatomic) NSString *author;
@property (nonatomic) NSString *description;

Code that crashes:

Book *book = [[Book alloc] init]; = nil

NSRange *rangeOfAuthor = NSMakeRange(0,

This happens because we are attempting to create the NSRange with a nil length.

The safe thing to do is:

if( != nil){
	NSRange *author = NSMakeRange(0,

So basically, anywhere a nil causes a crash, you will have to check for the case of nil.

In Swift… I like to think about objects being allowed to be defined in two ways:

  • Those that can exist as a nil
  • Those that can not exist as a nil

When you define a property or variable.. you tell the compiler whether this thing is the first or the second. If the property or variable you’re defining can (ever) exist as nil… then you must declare it as an optional. Ahhhh!!! Optionals.

Ok, it is not so bad! Let’s consider our book example. With a book, a name and author are probably items that we can say must always be there. i.e. The can never be nil. A book’s description is something that might not be available, however.. meaning it could exist as a nil.

One thing that’s quite swifty is to represent Book as a struct. This will aid us in forcing that name and author be present in every definition of a book.

struct Book {
    var name: String
    var author: String
    var description: String? //This is indicating the description is a property that could be nil (an optional!)

var b = Book()

The above declaration of b gives you an error. Defining a book as struct means that everytime we instantiate one, we must provide the properties it contains. As follows:

var b = Book(name: "Jean", author:"Auel", description: nil)

Notice if you try to set author to nil, you get a compilation error.

var b = Book(name: "Jean", author:nil, description: nil)

So, this means everytime we access a books name or author, we can be sure it will never be nil. This is safer all around as we DO NOT have to remember to check for nil in the cases we might see a crash.


Optionals allow:

  • You to be explicit about whether a variable of property must be present at all times.
  • To not have to explicitly check for nil in cases when it may cause a crash.
  • In doing the above, minimize likelyhood of crashes in your app.

(BTW, also) - Structs go a little further to enforce you create your object with the properties it is defined to have.

I’ve been learning Swift for a few months now and wrote my first function using generics today for a real world usecase.

Use case: merge two dictionaries, skipping duplicates. You’ve got to check for the same key types and value types.

extension Dictionary {
    func merge<K, V>(dict: [K: V]) -> [Key: Value]{
        var new: Dictionary<Key, Value> = [:]

        for (k, v) in self {
            new[k] = v

        for (k, v) in dict {
            if let key = k as? Key {
                new[key] = v as? Value
        return new
Clean Energy Landscape

With the Cop21 talks in Paris ending earlier this month… and the outcome being a global agreement to limit temperature increase to 2 degrees celcius, I wanted to capitalize on this momentum and ask myself what I, as a technologist, can do.

The agreement made speaks to limiting temperature, supporting developing countries to maintain growth, and keeping visibility into actions and compliance by all memebers. While there is vagueness about how this will be implemented, there is worldwide agreement that technology needs to be advanced in clean energy and related areas.

As a concerned citizen of the world and one that wants to leave it as beautiful as I’ve found it, I want to know what I, as a software engineer/technologist do to help? How can I contribute my largest asset, my tech skills, to help bring about this change?

Why 2 Degrees

In fact scientists actually believe we should not raise temperatures more than 1.5 degrees above pre-industrial averages. The graph below shows our potential CO2 emissions pathways for this century and their long-term impact on temperature.

What Needs to Change?

To achieve the aim of limiting temperature increase to 2 degrees celcius, we need to move away from getting most of our energy from fossil fuels. We need change to occur across governments, private investment, and societal comprehension/awareness of the problem and more. While I care about all of these, and technology can play a role in bringing these changes about, the largest technological changes need to happen in the energy system itself. So, what needs to change here?

Our current energy system is made up of the sourcing/production, movement, storage, and consumption of energy.

There’s space in all of these areas for major improvement. Let’s look at the current situation for each of these, where things need to get to.

Energy Production

The bottom line is that we need energy and we’re going to need more and more of it. We do have alternative, clean sources of energy available: solar, wind, geothermal, hydroelectric, biomass, and nuclear. But, today we largely rely on coal, oil and natural gas.

US energy usage breakdown 2014

Note that clean, renewable energy sources represent < 10%, with the bulk of that in nuclear (which is debatable in terms of cleanliness and long-term liability). These percentages need to shift.

What needs to change to bring these shifts about?

Energy Networks

Today, our energy grids are a relic of a 100+ year old system. The limitations of these networks represent where much innovation need to happen. Let’s look at each limitation and the changes needed.


In the Lawrence Livermore National Laboratory graph above, note that ‘rejected energy’ or energy produced, but lost and never consumed represents 59% of all the energy produced in the US. This is a huge area for improvement.


Our current electricity grids work on a realtime system. As in, when you pull electritiy off the grid and into your home to power your TV.. that electricity is a result of energy recently created at a power plant (probably by burning coal or natural gas). The idea is that the power plant predicts how much electricity will be demanded by consumers during any given hour of the day and they burn the appropriate level of coal or natural gas to provide that and put it out on the grid.

Currently wind and solar energy don’t integrate well. Solar energy is produced during the day (and sunny days at that) and wind is even more unpredictable.. although can provide energy at night. But, the issue is that they cannot currently be efficiently stored for later conversion and distribution onto the existing energy grid.

Whats needed here are better ways of storing renewable, clean energy for future use. There are a lot of interesting things happening here, but I’m going to dive into that in a future post.

Energy Location/Movement

Similar to the idea above, currently energy needs to be produced somewhat nearby to where it’s distributed and consumed. Wind farms in North Dakota cannot, now, efficiently have their energy transported for realtime consumption in Chicago.

Innovation needs to happen in both enabling energy production in many different environments and in new energy transportation networks that can efficiently move energy around where it’s needed.


It may come as no suprise, but the US and many other first world countries consume the most energy per person globally.

Part of the solution needs to be figuring out ways to use less dirty energy in our high consumption areas without a decrease in standard of living. If we look back at that Estimated U.S. Energy Use graph above, it shows that transportation is 27% of our annual energy usage. This is definitely an area to seek improvement and but it needs to move beyond this to more consumer areas and to the industrial sector as well.

These are definitely areas to seek improvement and watch as a technologist.


This blog post was an examination of the current clean energy landscape and the areas where we need to innovate to answer our energy dillema. If we truly need to ratchet down our CO2 to reach a temperature rise of under 2 degrees, we will need innovation across all these areas. And these are areas where a technologist can bring their skills. If not in the specific answers to say battery efficiency or energy grid waste, definitely in the consumer products and infrastructure that will be needed to adopt these advances across the US and around the world.