RailsConf 2016: Pat Packet visits Ruby Rails

Transcript

1. Pat Packet
   Visits
   Ruby Rails
   by: Jeremy Fairbank
   @elpapapollo | github.com/jfairbank
   illustrations: Marissa Roeper
   marissaroeper.com
   

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2. We help brands excel.
   pushagency.io
   Your website, SimplyBuilt.
   simplybuilt.com
   

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4. ?
   

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5. HTTP
   DNS
   TCP/IP
   ROUTING
   GET / HTTP/1.1
   

   Host: rubyonrails.org
   Accept: text/html
   Accept-Encoding: gzip, deflate, sdch
   Accept-Language: en-US,en;q=0.8
   Cache-Control: no-cache
   Connection: keep-alive
   

   Hello World
   The Message
   

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6. HTTP
   DNS
   TCP/IP
   ROUTING
   The Destination
   rubyonrails.org
   192.30.252.153
   

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7. The Transportation
   HTTP
   DNS
   TCP/IP
   ROUTING
   

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8. The Directions
   HTTP
   DNS
   TCP/IP
   ROUTING
   

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9. Package
   Address
   Continent
   Kingdom
   Train
   Router Station
   Network Packet
   IP Address
   Physical Device
   Software Server
   Connection
   Router/Switch
   Legend
   

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14. WAN - Wide Area Network
    The Internet
    LAN - Local Area Network
    Router + computers
    Protocol
    Official rules/guidelines to follow
    HTTP - Hyper Text Transfer Protocol
    Protocol for HTML, JSON, XML
    

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15. Can you send me
    your home page?
    Request
    Sure thing!
    Here you go!
    Reply
    

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16. GET / HTTP/1.1
    Host: rubyonrails.org
    Accept: text/html
    Accept-Encoding: gzip, deflate, sdch
    Accept-Language: en-US,en;q=0.8
    Cache-Control: no-cache
    Connection: keep-alive
    

    Hello World
    Request Line
    Method Resource HTTP Version HTTP Request
    Headers
    Optional
    Message
    

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17. GET
    POST
    PUT
    DELETE
    HTTP
    Methods
    

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18. GET Can you send me
    your home page?
    GET / HTTP/1.1
    POST
    PUT
    DELETE
    HTTP
    Methods
    

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19. GET Can you send me
    your home page?
    POST Here is my shopping
    cart for checkout.
    PUT
    DELETE
    POST /checkout HTTP/1.1
    HTTP
    Methods
    

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20. GET Can you send me
    your home page?
    POST Here is my shopping
    cart for checkout.
    PUT I changed my name. Can you
    please update your records?
    DELETE
    PUT /user/info HTTP/1.1
    HTTP
    Methods
    

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21. GET Can you send me
    your home page?
    POST Here is my shopping
    cart for checkout.
    PUT I changed my name. Can you
    please update your records?
    DELETE I no longer use this address.
    Can you remove it?
    DELETE /address/2 HTTP/1.1
    HTTP
    Methods
    

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22. Meta data is like saying
    I’d prefer the list of
    friends in HTML.
    Data is like saying
    Please send me a list
    of my friends.
    HTTP Headers
    

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23. Accept: */*
    Accept: text/html
    Content-Type: application/json
    Host: rubyonrails.org
    Content-Length: 42
    Key Value
    HTTP Headers
    

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24. Send back
    whatever you have.
    Accept: */*
    Accept: text/html
    Content-Type: application/json
    Host: rubyonrails.org
    Content-Length: 42
    Key Value
    HTTP Headers
    

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25. Send back HTML
    please.
    Accept: */*
    Accept: text/html
    Content-Type: application/json
    Host: rubyonrails.org
    Content-Length: 42
    Key Value
    HTTP Headers
    

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26. I’m sending you
    some JSON.
    Accept: */*
    Accept: text/html
    Content-Type: application/json
    Host: rubyonrails.org
    Content-Length: 42
    Key Value
    HTTP Headers
    

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27. Please give this
    message to
    rubyonrails.org.
    Accept: */*
    Accept: text/html
    Content-Type: application/json
    Host: rubyonrails.org
    Content-Length: 42
    Key Value
    HTTP Headers
    

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28. Here’s how much
    information I’m
    sending.
    Accept: */*
    Accept: text/html
    Content-Type: application/json
    Host: rubyonrails.org
    Content-Length: 42
    Key Value
    HTTP Headers
    

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29. Status Line
    Headers
    Message
    HTTP/1.1 200 OK
    Server: GitHub.com
    Date: Sun, 17 Apr 2016 11:19:48 GMT
    Content-Type: text/html; charset=utf-8
    Content-Length: 4127
    Last-Modified: Tue, 01 Mar 2016
    10:32:49 GMT
    

    Ruby on Rails!
    HTTP
    Version
    Status
    Code
    Status
    Description
    HTTP Reply
    

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30. 200
    304
    404
    401
    500
    HTTP
    Statuses
    

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31. HTTP/1.1 200 OK
    200 All good. Here’s
    your reply.
    304
    404
    401
    500
    HTTP
    Statuses
    

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32. HTTP/1.1 304 Not Modified
    200 All good. Here’s
    your reply.
    304 Nothing changed. Keep
    what you already have.
    404
    401
    500
    HTTP
    Statuses
    

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33. HTTP/1.1 404 Not Found
    200 All good. Here’s
    your reply.
    304 Nothing changed. Keep
    what you already have.
    404 Sorry, I can’t
    find that.
    401
    500
    HTTP
    Statuses
    

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34. HTTP/1.1 401 Unauthorized
    200 All good. Here’s
    your reply.
    304 Nothing changed. Keep
    what you already have.
    404 Sorry, I can’t
    find that.
    401 Sorry, you’re not allowed
    to request that.
    500
    HTTP
    Statuses
    

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35. HTTP/1.1 500 Internal Server Error
    200 All good. Here’s
    your reply.
    304 Nothing changed. Keep
    what you already have.
    404 Sorry, I can’t
    find that.
    401 Sorry, you’re not allowed
    to request that.
    500 Sorry, we’re having
    problems right now.
    HTTP
    Statuses
    

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36. GET / HTTP/1.1
    Host: rubyonrails.org
    Accept: text/html
    Accept-Encoding: gzip, deflate, sdch
    Accept-Language: en-US,en;q=0.8
    Cache-Control: no-cache
    Connection: keep-alive
    

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37. DNS - Domain Name System
    Where is
    rubyonrails.org?
    Oh, you can find it
    at 192.30.252.153.
    Translate
    domain names
    into IP addresses.
    Client DNS Server
    

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47. Local Resolver
    (e.g. at internet
    service provider)
    Root Kingdoms
    DNS
    

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48. Local Resolver
    (e.g. at internet
    service provider)
    rubyonrails.org?
    RECURSIVE
    Root Kingdoms
    DNS
    

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49. Local Resolver
    (e.g. at internet
    service provider)
    rubyonrails.org?
    RECURSIVE
    Root Kingdoms
    DNS
    ?
    ITERATIVE
    (keep trying)
    

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50. Local Resolver
    (e.g. at internet
    service provider)
    rubyonrails.org?
    RECURSIVE
    Root Kingdoms
    DNS
    TLDs
    .org
    .com
    .net
    .io
    ?
    ITERATIVE
    (keep trying)
    

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51. Local Resolver
    (e.g. at internet
    service provider)
    rubyonrails.org?
    RECURSIVE
    Root Kingdoms
    DNS
    TLDs
    .org
    .com
    .net
    .io
    NS
    a0.org…
    a2.org…
    ?
    Try these
    kingdoms.
    ITERATIVE
    (keep trying)
    

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52. Local Resolver
    (e.g. at internet
    service provider)
    TLD Kingdoms
    DNS
    NS Kingdoms
    

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53. Local Resolver
    (e.g. at internet
    service provider)
    TLD Kingdoms
    DNS
    Please associate
    rubyonrails.org with
    my IP address.
    ns1.gratisdns.dk.
    ns2.gratisdns.dk.
    NS Kingdoms
    Please associate us
    with rubyonrails.org.
    

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54. Local Resolver
    (e.g. at internet
    service provider)
    TLD Kingdoms
    DNS
    ?
    NS
    ns1.gratisdns.dk.
    ns2.gratisdns.dk.
    Try these
    kingdoms.
    NS Kingdoms
    

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55. Local Resolver
    (e.g. at internet
    service provider)
    DNS
    NS Kingdoms
    

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56. Local Resolver
    (e.g. at internet
    service provider)
    DNS
    NS Kingdoms
    rubyonrails.org?
    

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57. Local Resolver
    (e.g. at internet
    service provider)
    DNS
    NS Kingdoms
    rubyonrails.org?
    A 192.30.252.153
    

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58. Local Resolver
    (e.g. at internet
    service provider)
    DNS
    NS Kingdoms
    rubyonrails.org?
    A 192.30.252.153
    rubyonrailsftw.com?
    

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59. Local Resolver
    (e.g. at internet
    service provider)
    DNS
    NS Kingdoms
    rubyonrails.org?
    A 192.30.252.153
    rubyonrailsftw.com?
    CNAME rubyonrails.org.
    

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60. Local Resolver
    (e.g. at internet
    service provider)
    Root Kingdoms
    TLD Kingdoms
    DNS
    NS Kingdoms
    A
    Hierarchy
    

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61. Local Resolver
    (e.g. at internet
    service provider)
    Root Kingdoms
    TLD Kingdoms
    DNS
    NS Kingdoms
    A
    Hierarchy
    

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62. x 4 billion IP addresses
    = LOTS of storage
    Can you all update
    my address?
    

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65. TCP/IP
    Transmission Control Protocol
    

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66. TCP/IP
    Transmission Control Protocol
    

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67. View Slide

68. ACKnowledging
    the package.
    Here’s your reply.
    ACK
    

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69. ACKnowledging
    the package.
    Here’s your reply.
    ACK
    I’m not sure you
    got that package.
    I’ll try again!
    ?
    X
    

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70. View Slide

71. X
    X
    X
    X
    X
    X
    X X
    X
    X
    X
    X
    X
    Congestion
    

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72. Sliding
    Window
    (being delivered)
    Awaiting
    delivery
    1
    TCP Congestion Control
    

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73. Sliding
    Window
    (being delivered)
    Awaiting
    delivery
    1
    1
    TCP Congestion Control
    

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74. Sliding
    Window
    (being delivered)
    Awaiting
    delivery
    1
    ACK 1
    1
    TCP Congestion Control
    

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75. ACK 1
    1
    Awaiting
    delivery
    2
    Delivered
    Sliding
    Window
    (being delivered)
    TCP Congestion Control
    

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76. 2
    3
    ACK 1
    1
    Awaiting
    delivery
    2
    Delivered
    Sliding
    Window
    (being delivered)
    TCP Congestion Control
    

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77. 2
    3
    ACK 1
    1
    Awaiting
    delivery
    2
    Delivered
    Sliding
    Window
    (being delivered)
    TCP Congestion Control
    X
    X
    

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78. 2
    3
    ACK 1
    1
    Awaiting
    delivery
    1
    Delivered
    Sliding
    Window
    (being delivered)
    TCP Congestion Control
    X
    X
    

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79. 2
    3
    ACK 1
    1
    Awaiting
    delivery
    1
    Delivered
    Sliding
    Window
    (being delivered)
    TCP Congestion Control
    X
    X
    2
    

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81. TCP Connections - 3 way handshake
    

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82. SYN
    TCP Connections - 3 way handshake
    1. Client (requester) requests connection with SYNchronize packet.
    1
    

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83. ACK-SYN
    Window = 1
    SYN
    TCP Connections - 3 way handshake
    1. Client (requester) requests connection with SYNchronize packet.
    2. Server (recipient) ACKnowledges SYN and sends its own SYN. Server
    can specify initial window size to prevent too much coming in.
    1
    2
    

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84. ACK-SYN
    Window = 1
    SYN
    TCP Connections - 3 way handshake
    ACK
    1. Client (requester) requests connection with SYNchronize packet.
    2. Server (recipient) ACKnowledges SYN and sends its own SYN. Server
    can specify initial window size to prevent too much coming in.
    3. Client ACKnowledges server’s SYN and connection is established.
    1
    3
    2
    

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85. View Slide

86. 1
    Sliding Window
    1
    2
    2
    1
    Sequence
    Numbers
    

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87. 1
    Sliding Window
    1
    2
    2
    1
    Sequence
    Numbers
    Got #1…
    ACK 1
    

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88. Sliding Window
    1
    2
    2
    1
    Sequence
    Numbers
    Got #1…
    And #2!
    2
    ACK 1
    ACK 2
    

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89. View Slide

90. View Slide

91. Destination Next Hop
    23.235.44.0/24 192.168.1.1
    104.0.0.0/8 192.168.2.1
    192.30.0.0/16 192.168.3.1
    23.21.0.0/16 192.168.4.1
    Routing Tables
    Tell which location to go to next for a range of IP
    addresses.
    IP Address Range
    with CIDR
    Path to follow,
    i.e. the next router
    

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92. CIDR — Classless Inter-domain Routing
    192.30.0.0/16
    

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93. 192.30.252.153
    8 bits = 2^8 = 256 numbers => 0-255
    4 of 2^8 => 0-255.0-255.0-255.0-255
    IPV4 Addresses - Dotted Quads
    0—255
    1st quad
    0—255
    2nd quad
    0—255
    3rd quad
    0—255
    4th quad
    

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94. CIDR — Classless Inter-domain Routing
    192.30.0.0/16
    192.30.0.0/8
    1. Use the first /8 bits
    to mask the first
    quad. Masks “lock”
    a number in.
    2. Use the next /8 bits
    to mask the second
    quad.
    3. This leaves a range
    of possible IP
    addresses to find a
    match in.
    192.30.0.0/0
    192.30.0-255.0-255
    -or-
    192.30.0.0 - 192.30.255.255
    

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95. Destination Next Hop
    23.235.44.0/24 192.168.1.1
    192.30.0.0/16 192.168.3.1
    23.21.0.0/16 192.168.4.1
    Destination Next Hop
    107.20.0.0/16 192.168.5.1
    192.30.252.0/24 192.168.6.1
    Destination Next Hop
    192.30.252.50.144/28 192.168.7.1
    192.30.0.0/16 192.168.8.1
    192.30.252.153?
    Routing
    Range grows smaller and more specific (mask grows larger).
    

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98. Router Buffer
    (hold unprocessed
    packets)
    

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99. Router Buffer
    (hold unprocessed
    packets)
    

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100. Router Buffer
     (hold unprocessed
     packets)
     No room for packets.
     They must be dropped.
     Requester must try again and
     potentially slow down sending
     rate.
     

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101. Router Buffer
     (hold unprocessed
     packets)
     No room for packets.
     They must be dropped.
     Requester must try again and
     potentially slow down sending
     rate.
     Slow down
     please!
     X X
     

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102. Router Buffer
     (hold unprocessed
     packets)
     No room for packets.
     They must be dropped.
     Requester must try again and
     potentially slow down sending
     rate.
     Slow down
     please!
     X X
     

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107. GET / HTTP/1.1
     Host: rubyonrails.org
     Accept: text/html
     Accept-Encoding: gzip, deflate, sdch
     Accept-Language: en-US,en;q=0.8
     Cache-Control: no-cache
     Connection: keep-alive
     

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110. DNS
     Destination Next Hop
     192.30.0.0/16 192.168.3.1
     Routing
     TCP/IP
     ACK
     Recap
     

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111. DNS
     Destination Next Hop
     192.30.0.0/16 192.168.3.1
     Routing
     TCP/IP
     ACK
     Recap
     

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112. • Physical distance and latency unavoidable
     • Persistent/shared TCP connections
     • Caching DNS queries
     • Caching HTML, scripts, images, etc.
     • Content distribution networks (CDNs) and mirrors
     • HTTP 2
     Performance Matters!
     

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113. • https://commons.wikimedia.org/wiki/File:Cartoon_cloud.svg
     • https://commons.wikimedia.org/wiki/File:Checkmark_green.svg
     • https://commons.wikimedia.org/wiki/File:Computer.svg
     • https://commons.wikimedia.org/wiki/File:Gnome-web-browser.svg
     • https://commons.wikimedia.org/wiki/File:Modern_clock_chris_kemps_01.svg
     • https://commons.wikimedia.org/wiki/File:Network-server.svg
     • https://commons.wikimedia.org/wiki/File:Server-web.svg
     • https://commons.wikimedia.org/wiki/File:Server.svg
     • https://commons.wikimedia.org/wiki/File:Simple_crown_icon.svg
     • https://pixabay.com/en/metro-subway-tramway-159004/
     • https://pixabay.com/en/postal-parcel-post-package-32383/
     • https://pixabay.com/en/subway-map-transportation-metro-576776/
     • https://upload.wikimedia.org/wikipedia/commons/3/3e/I-80_Eastshore_Fwy.jpg
     • https://commons.wikimedia.org/wiki/File:Osa_device-wireless-router.svg
     Sources
     

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114. Acknowledgement
     Illustrations by Marissa Roeper
     marissaroeper.com
     

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115. Thanks!
     by: Jeremy Fairbank
     @elpapapollo | github.com/jfairbank
     illustrations: Marissa Roeper
     marissaroeper.com
     

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