Technical Practices for Sustainable Code

Highly maintainable code is hard to produce.
Without maintainability we can not have sustainable code, it will rot and have to be re-written. As an industry we're often given principles to follow which sound FANTASTIC... but don't layout the "how" of reaching these ideals.
We'll go into detail of four technical practices that have the biggest impact towards improving maintainability of the code we write.
As agile developers, what we want to do is deliver value to the customer quickly and consistently. As an agile developer and team, coding technical practices are the only way to develop code to quickly and consistently deliver value to the customer for the life of the product.
These technical practices produce simple, understandable, testable code which results in extremely maintainable code that we'll be able to enjoy working on for a long time.

Transcript

1. Feature Parity in
   25% of the Dev Hours
   with
   Technical Practices for
   Sustainable Code
   @TheQuinnGil QuinnGil.com
   

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2. Feature Parity in
   25% of the Dev Hours
   @TheQuinnGil QuinnGil.com
   

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3. @TheQuinnGil QuinnGil.com
   Technical Practices for
   Sustainable Code
   

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4. Quinn Gil
   Blog -- QuinnGil.com
   Twitter -- TheQuinnGil
   Github -- Fyzxs
   @TheQuinnGil QuinnGil.com
   

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5. This is for you.
   

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6. Sustainable Code
   through
   Technical Practices
   @TheQuinnGil QuinnGil.com
   

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7. Sustainable Code
   through
   Technical Practices
   @TheQuinnGil QuinnGil.com
   

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8. Sustainable Code
   through
   Technical Practices
   @TheQuinnGil QuinnGil.com
   

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9. Tests
   

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10. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    @TheQuinnGil QuinnGil.com
    

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11. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    No Getters / No Setters
    @TheQuinnGil QuinnGil.com
    

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12. Technical Practices - No Getters / No Setters
    class FizzBuzzBag
    {
    public int Input { get; set; }
    public string Result { get; set; }
    }
    class FizzBuzzBag:
    def __init__(self):
    self._result = None
    self._input = None
    @property
    def result(self):
    return self._result
    @result.setter
    def result(self, value):
    self._result = value
    @property
    def input(self):
    return self._input
    @input.setter
    def input(self, value):
    self._input = value
    class FizzBuzzBag{
    private int input;
    private String result;
    public String getResult(){
    return result;
    }
    public void setResult(String value){
    result = value;
    }
    public int getInput(){
    return input;
    }
    public void setInput(int value){
    input = value;
    }
    }
    class FizzBuzzBag
    attr_accessor :input
    attr_accessor :result
    end
    

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13. Technical Practices - No Getters / No Setters
    No Way
    

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14. No Getters / No Setters
    Technical Practices
    

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15. Technical Practices - No Getters
    Why No Getters?
    

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16. Technical Practices - No Setters
    Why No Setters?
    

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17. Technical Practices - No Getters / No Setters
    How?
    

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18. No Getters / No Setters - How?
    The Class Does It
    

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19. Technical Practices - No Getters / No Setters
    public class FizzBuzz{
    public int Input { get; set; }
    public string Result { get; set; }
    }
    public static class FizzBuzzUtils{
    public static void Calculate(FizzBuzz fb){
    if (fb.Input % 3 == 0){
    fb.Result = "Fizz";
    }
    if (fb.Input % 5 == 0){
    if (fb.Result == null){
    fb.Result = "Buzz";
    } else {
    fb.Result += "Buzz";
    }
    }
    if (string.IsNullOrEmpty(fb.Result)){
    fb.Result = fb.Input.ToString();
    }
    }
    }
    

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20. Technical Practices - No Getters / No Setters
    public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    string result = null;
    if (_input % 3 == 0) result = "Fizz";
    if (_input % 5 == 0){
    if (result == null) result = "Buzz";
    else result += "Buzz";
    }
    if (string.IsNullOrEmpty(result)){
    result = _input.ToString();
    }
    return result;
    }
    }
    public class FizzBuzz{
    public int Input { get; set; }
    public string Result { get; set; }
    }
    public static class FizzBuzzUtils{
    public static void Calculate(FizzBuzz fb){
    if (fb.Input % 3 == 0){
    fb.Result = "Fizz";
    }
    if (fb.Input % 5 == 0){
    if (fb.Result == null){
    fb.Result = "Buzz";
    } else {
    fb.Result += "Buzz";
    }
    }
    if (string.IsNullOrEmpty(fb.Result)){
    fb.Result = fb.Input.ToString();
    }
    }
    }
    

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21. Technical Practices - No Getters / No Setters
    Benefits
    

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22. Sustainable Code through Technical Practices
    No Getters / No Setters
    @TheQuinnGil QuinnGil.com
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    

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23. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    `if` Only As Guard Clause
    @TheQuinnGil QuinnGil.com
    

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24. Technical Practices - `if` Only As Guard Clause
    No Way
    

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25. Technical Practices - `if` Only As Guard Clause
    Default Path
    

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26. `if` Only As Guard Clause - Default Path
    public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    string result = null;
    if (_input % 3 == 0) result = "Fizz";
    if (_input % 5 == 0){
    if (result == null) result = "Buzz";
    else result += "Buzz";
    }
    if (string.IsNullOrEmpty(result)){
    result = _input.ToString();
    }
    return result;
    }
    }
    

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27. public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    string result = null;
    if (_input % 3 == 0) result = "Fizz";
    if (_input % 5 == 0){
    if (result == null) result = "Buzz";
    else result += "Buzz";
    }
    if (string.IsNullOrEmpty(result)){
    result = _input.ToString();
    }
    return result;
    }
    }
    `if` Only As Guard Clause - Default Path
    public class FizzBuzz{
    private int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    if (_input % 15 == 0) return "FizzBuzz";
    if (_input % 3 == 0) return "Fizz";
    if (_input % 5 == 0) return "Buzz";
    return _input.ToString();
    }
    }
    

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28. Technical Practices - `if` Only As Guard Clause
    Cascading Changes
    

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29. Technical Practices - `if` Only As Guard Clause
    Cascading Changes
    switch and else - always evil
    

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30. Technical Practices - `if` Only As Guard Clause
    How?
    

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31. `if` Only As Guard Clause - Default Path
    public class FizzBuzz{
    private int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    if (_input % 15 == 0) return "FizzBuzz";
    if (_input % 3 == 0) return "Fizz";
    if (_input % 5 == 0) return "Buzz";
    return _input.ToString();
    }
    }
    public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    string result = null;
    if (_input % 3 == 0) result = "Fizz";
    if (_input % 5 == 0){
    if (result == null) result = "Buzz";
    else result += "Buzz";
    }
    if (string.IsNullOrEmpty(result)){
    result = _input.ToString();
    }
    return result;
    }
    }
    

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32. Sustainable Code through Technical Practices
    `if` Only As Guard Clause
    @TheQuinnGil QuinnGil.com
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    

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33. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    Isolate Their Code
    @TheQuinnGil QuinnGil.com
    

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34. Technical Practices - Isolate Their Code - 3rd Party
    public class FizzBuzz{
    private readonly string _input;
    public FizzBuzz(string input) => _input = input;
    public string Result(){
    JObject jObject = JObject.Parse(_input);
    int input = jObject.Value("number");
    if (IsFizzBuzz(input)) return "FizzBuzz";
    if (IsFizz(input)) return "Fizz";
    if (IsBuzz(input)) return "Buzz";
    return input.ToString();
    }
    }
    

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35. Technical Practices - Isolate Their Code - 3rd Party
    public class FizzBuzz{
    private readonly string _input;
    private readonly IParser _parser;
    public string Result(){
    IParsedObject pObject = _parser.Parse(_input);
    int input = pObject.IntValue("input");
    if (IsFizzBuzz(input)) return "FizzBuzz";
    if (IsFizz(input)) return "Fizz";
    if (IsBuzz(input)) return "Buzz";
    return input.ToString();
    }
    }
    

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36. What Else?
    Technical Practices - Isolate Their Code
    

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37. Operating System
    Technical Practices - Isolate Their Code
    

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38. How?
    Technical Practices - Isolate Their Code
    

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39. Technical Practices - Isolate Their Code - How?
    internal class HttpClientBookEnd : IHttpClientBookEnd
    {
    private static HttpClient _testClient;
    #if DEBUG
    public static void SetTestClient(HttpClient testClient) => _testClient = testClient;
    #endif
    private readonly HttpClient _httpClient;
    public HttpClientBookEnd() : this(new HttpClient()) { }
    private HttpClientBookEnd(HttpClient httpClient) => _httpClient = httpClient;
    public void SendRequestAsync(HttpRequestMessage msg) => HttpClient().SendAsync(msg);
    private HttpClient HttpClient() => _testClient ?? _httpClient;
    }
    

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40. User Interface
    Technical Practices - Isolate Their Code
    

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41. Sustainable Code through Technical Practices
    Isolate Their Code
    @TheQuinnGil QuinnGil.com
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    

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42. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    Never `null`
    @TheQuinnGil QuinnGil.com
    

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43. Why?
    Technical Practices - Never `null`
    

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44. How?
    Technical Practices - Never `null`
    

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45. Technical Practices - Never `null`
    public string CalculateThing(ICanBeNull canBeNull)
    {
    if (canBeNull == null) return "Default";
    IAlsoNull alsoNull = canBeNull.Example();
    if (alsoNull == null) return "Default";
    string sample = alsoNull.Sample();
    if (sample == null) return "Default";
    return sample;
    }
    

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46. Technical Practices - Never `null`
    public string CalculateThing(ICanBeNull canBeNull)
    {
    if (canBeNull == null) return "Default";
    IAlsoNull alsoNull = canBeNull.Example();
    if (alsoNull == null) return "Default";
    string sample = alsoNull.Sample();
    if (sample == null) return "Default";
    return sample;
    }
    public string CalculateThing(ICanBeNull canBeNull)
    {
    return canBeNull?.Example()?.Sample() ?? "Default";
    }
    

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47. Technical Practices - Never `null`
    public string CalculateThing(ICanBeNull canBeNull)
    {
    if (canBeNull == null) return "Default";
    IAlsoNull alsoNull = canBeNull.Example();
    if (alsoNull == null) return "Default";
    string sample = alsoNull.Sample();
    if (sample == null) return "Default";
    return sample;
    }
    public string CalculateThing(ICanBeNull canBeNull)
    {
    return canBeNull?.Example()?.Sample() ?? "Default";
    }
    public string CalculateThing(ICanNotBeNull canNotBeNull)
    {
    return canNotBeNull.Example().Sample();
    }
    

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48. Technical Practices - Never `null`
    public string CalculateThing(ICanBeNull canBeNull)
    {
    if (canBeNull == null) return "Default";
    IAlsoNull alsoNull = canBeNull.Example();
    if (alsoNull == null) return "Default";
    string sample = alsoNull.Sample();
    if (sample == null) return "Default";
    return sample;
    }
    public string CalculateThing(ICanBeNull canBeNull)
    {
    return canBeNull?.Example()?.Sample() ?? "Default";
    }
    public string CalculateThing(ICanNotBeNull canNotBeNull)
    {
    return canNotBeNull.Example().Sample();
    }
    public void Foo()
    {
    string thing = _bar.CalculateThing(_canBeNull);
    //...
    }
    

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49. Technical Practices - Never `null`
    public string CalculateThing(ICanBeNull canBeNull)
    {
    if (canBeNull == null) return "Default";
    IAlsoNull alsoNull = canBeNull.Example();
    if (alsoNull == null) return "Default";
    string sample = alsoNull.Sample();
    if (sample == null) return "Default";
    return sample;
    }
    public string CalculateThing(ICanBeNull canBeNull)
    {
    return canBeNull?.Example()?.Sample() ?? "Default";
    }
    public string CalculateThing(ICanNotBeNull canNotBeNull)
    {
    return canNotBeNull.Example().Sample();
    }
    public void Foo()
    {
    string thing = _bar.CalculateThing(_canBeNull);
    //...
    }
    public void Foo()
    {
    string thing = _canNotBeNull.Example().Sample();
    //...
    }
    

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50. Technical Practices - Never `null`
    public class NullObject : ICanNotBeNull
    {
    public IAlsoNotNull Example() => new NullObjectAlso();
    }
    public class NullObjectAlso : IAlsoNotNull
    {
    public string Sample() => "Default";
    }
    public string CalculateThing(ICanBeNull canBeNull)
    {
    if (canBeNull == null) return "Default";
    IAlsoNull alsoNull = canBeNull.Example();
    if (alsoNull == null) return "Default";
    string sample = alsoNull.Sample();
    if (sample == null) return "Default";
    return sample;
    }
    public void Foo()
    {
    string thing = _canNotBeNull.Example().Sample();
    //...
    }
    

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51. Languages and Null
    

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52. Sustainable Code through Technical Practices
    Never `null`
    @TheQuinnGil QuinnGil.com
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    

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53. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    No `new` inline
    @TheQuinnGil QuinnGil.com
    

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54. Technical Practices - No `new` inline
    public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    if (new Mod15(_input).Remainder() == 0) return "FizzBuzz";
    if (new Mod3(_input).Remainder() == 0) return "Fizz";
    if (new Mod5(_input).Remainder() == 0) return "Buzz";
    return _input.ToString();
    }
    }
    

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55. Technical Practices - No `new` inline
    public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    if (Mod15().Remainder() == 0) return "FizzBuzz";
    if (Mod3().Remainder() == 0) return "Fizz";
    if (Mod5().Remainder() == 0) return "Buzz";
    return _input.ToString();
    }
    private IRemainder Mod15() => new Mod15(_input);
    private IRemainder Mod3() => new Mod3(_input);
    private IRemainder Mod5() => new Mod5(_input);
    }
    

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56. Technical Practices - No `new` inline
    public class FizzBuzz{
    private readonly int _input;
    private readonly ModFactory factory;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    if (factory.Mod15(_input).Remainder() == 0) return "FizzBuzz";
    if (factory.Mod3(_input).Remainder() == 0) return "Fizz";
    if (factory.Mod5(_input).Remainder() == 0) return "Buzz";
    return _input.ToString();
    }
    }
    public class ModFactory{
    public IRemainder Mod15(int input) => new Mod15(input);
    public IRemainder Mod3(int input) => new Mod3(input);
    public IRemainder Mod5(int input) => new Mod5(input);
    }
    

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57. Where DO we Create?
    Technical Practices
    

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58. No `new` inline - Where DO We Create?
    public class FizzBuzz{
    public string Result(){
    IFizzBuzzInput input = new FizzBuzzInput();
    if (input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (input.EvenlyDivisibleBy(3)) return "Fizz";
    if (input.EvenlyDivisibleBy(5)) return "Buzz";
    return input.ToString();
    }
    }
    

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59. No `new` inline - Where DO We Create?
    public class FizzBuzz{
    private readonly IFizzBuzzInput _input;
    public FizzBuzz() : this(new FizzBuzzInput()) { }
    private FizzBuzz(IFizzBuzzInput fizzBuzzInput)
    => _input = fizzBuzzInput;
    public string Result(){
    if (_input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (_input.EvenlyDivisibleBy(3)) return "Fizz";
    if (_input.EvenlyDivisibleBy(5)) return "Buzz";
    return _input.ToString();
    }
    }
    public class FizzBuzz{
    public string Result(){
    IFizzBuzzInput input = new FizzBuzzInput();
    if (input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (input.EvenlyDivisibleBy(3)) return "Fizz";
    if (input.EvenlyDivisibleBy(5)) return "Buzz";
    return input.ToString();
    }
    }
    

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60. No `new` inline - Where DO We Create?
    public class FizzBuzz{
    private readonly IFizzBuzzService _service;
    public FizzBuzz() : this(new FizzBuzzService()) { }
    private FizzBuzz(IFizzBuzzService fizzBuzzService)
    => _service = fizzBuzzService;
    public string Result(){
    IFizzBuzzInput input = _service.FizzBuzzInput();
    if (input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (input.EvenlyDivisibleBy(3)) return "Fizz";
    if (input.EvenlyDivisibleBy(5)) return "Buzz";
    return input.ToString();
    }
    } public class FizzBuzzService : IFizzBuzzService {
    public IFizzBuzzInput FizzBuzzInput()
    {
    return new FizzBuzzInputFromNetwork(_foo);
    }
    }
    

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61. Just Two Places
    No `new` inline
    

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62. Why?
    No `new` inline
    

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63. Testability
    No `new` inline - Why?
    

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64. No `new` inline - Why? - Testability
    public class FizzBuzz{
    private readonly IFizzBuzzInput _input;
    public FizzBuzz() : this(new FizzBuzzInput()) { }
    private FizzBuzz(IFizzBuzzInput fizzBuzzInput)
    => _input = fizzBuzzInput;
    public string Result(){
    if (_input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (_input.EvenlyDivisibleBy(3)) return "Fizz";
    if (_input.EvenlyDivisibleBy(5)) return "Buzz";
    return _input.ToString();
    }
    }
    

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65. No `new` inline - Why? - Testability
    public class FizzBuzz{
    private readonly IFizzBuzzInput _input;
    public FizzBuzz() : this(new FizzBuzzInput()) { }
    private FizzBuzz(IFizzBuzzInput fizzBuzzInput)
    => _input = fizzBuzzInput;
    public string Result(){
    if (_input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (_input.EvenlyDivisibleBy(3)) return "Fizz";
    if (_input.EvenlyDivisibleBy(5)) return "Buzz";
    return _input.ToString();
    }
    }
    public class FizzBuzz{
    private readonly IFizzBuzzService _service;
    public FizzBuzz() : this(new FizzBuzzService()) { }
    private FizzBuzz(IFizzBuzzService fizzBuzzService)
    => _service = fizzBuzzService;
    public string Result(){
    IFizzBuzzInput input = _service.FizzBuzzInput();
    if (input.EvenlyDivisibleBy(15)) return "FizzBuzz";
    if (input.EvenlyDivisibleBy(3)) return "Fizz";
    if (input.EvenlyDivisibleBy(5)) return "Buzz";
    return input.ToString();
    }
    }
    

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66. Expose Existing Cohesion
    No `new` inline - Why?
    

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67. No `new` inline - Why? - Expose Existing Cohesion
    public class FizzBuzz{
    private readonly int _input;
    public FizzBuzz(int input) => _input = input;
    public string Result(){
    if (new Mod15(_input).IsMultipleOf()) return "FizzBuzz";
    if (new Mod3(_input).IsMultipleOf()) return "Fizz";
    if (new Mod5(_input).IsMultipleOf()) return "Buzz";
    return _input.ToString();
    }
    }
    

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68. No `new` inline - Why? - Expose Existing Cohesion
    public class FizzBuzz{
    public FizzBuzz(int input):this(input,
    new Mod15(input),
    new Mod3(input),
    new Mod5(input))
    public string Result(){
    if (_mod15.IsMultipleOf()) return "FizzBuzz";
    if (_mod3.IsMultipleOf()) return "Fizz";
    if (_mod5.IsMultipleOf()) return "Buzz";
    return _input.ToString();
    }
    }
    

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69. No `new` inline - Why? - Expose Existing Cohesion
    public class FizzBuzz{
    public FizzBuzz(int input):this(new IntToString(input),
    new Mod15(input),
    new Mod3(input),
    new Mod5(input))
    public string Result(){
    if (_mod15.IsMultipleOf()) return "FizzBuzz";
    if (_mod3.IsMultipleOf()) return "Fizz";
    if (_mod5.IsMultipleOf()) return "Buzz";
    return _toString.Value();
    }
    }
    

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70. No `new` inline - Why? - Expose Existing Cohesion
    public class FizzBuzz{
    public FizzBuzz(int input):this(new IntToString(input),
    new Mod15(input),
    new Mod3(input),
    new Mod5(input))
    public string Result(){
    if (_mod15.IsMultipleOf()) return _mod15.Value();
    if (_mod3.IsMultipleOf()) return _mod3.Value();
    if (_mod5.IsMultipleOf()) return _mod5.Value();
    return _toString.Value();
    }
    }
    

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71. No `new` inline - Why? - Expose Existing Cohesion
    public class FizzBuzz{
    public FizzBuzz(int input):this(new ToStringResult(input),
    new FizzBuzzResult(input),
    new FizzResult(input),
    new BuzzResult(input))
    public string Result(){
    if (_fizzBuzz.ShouldReturn()) return _fizzBuzz.Value();
    if (_buzz.ShouldReturn()) return _buzz.Value();
    if (_fizz.ShouldReturn()) return _fizz.Value();
    return _toString.Value();
    }
    }
    

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72. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    No `new` inline
    @TheQuinnGil QuinnGil.com
    

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73. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    @TheQuinnGil QuinnGil.com
    

    View Slide

74. Feature Parity in
    25% of the Dev Hours
    @TheQuinnGil QuinnGil.com
    

    View Slide

75. THANK YOU!
    @TheQuinnGil QuinnGil.com
    

    View Slide

76. Sustainable Code through Technical Practices
    ● No Getters / No Setters
    ● `if` Only As Guard Clause
    ● Isolate Their Code
    ● Never `null`
    ● No `new` inline
    ● Composition, Not Inheritance
    ●
    ● Be Immutable
    ● No Primitives
    ● Extract Cohesion
    ● No Public Statics
    ● Never Reflection
    @TheQuinnGil QuinnGil.com
    

    View Slide