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Archive for May 2011

Notes from Kyle Neath’s presentation at Twitter on 5/31

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  • Slides http://warpspire.com/talks/responsive/
  • hashbang urls
    • are a kludgy workaround for lack of history api. Since history api is coming, they have no future. Since urls are forever, especially w/ tweets being stored in the lib of congress, use of hashbangs results in permanent support for a temporary condition.
    • break pre-existing url fragment behavior
    • result in confusing routing logic
  • “responsive web design” is adapting to client and seeming responsive to user input
    • page load isn’t just a benchmark; a page is only “loaded” when the user can scroll, read text, and click links
  • well-designed urls provide a command-line-like interface for web apps
  • all web assets should have a url, i.e., navigation should not allow access to a resource that cannot then be accessed directly via a url
  • native elements should behave as the user expects
    • do not modify common key combos, e.g., shift + click
    • take advantage of the back button, tabs, links, etc
  • responsiveness is as much about performance as perception
    • wait ~500ms before showing loader image; showing loaders immediately can actually make the page seem slower
  • ssl
    • is required now that there are common, easy ways to sniff credentials
    • a new ssl handshake is very slow, and required for each domain
    • use http keep-alive to reuse ssl connections
    • multiple parallel requests to a new domain will each have to perform a handshake; instead, complete one fast request, and then reuse the connection for subsequent parallel requests
    • github optimized its backend to 40ms latency before realizing that the ssl handshake takes 500ms
      • a case of perception > performance
      • favor science over theory, i.e., test time-to-usable in multiple regions instead of just running perf tests on components
    • templates
    • use something simple, e.g., mustache
    • avoid rendering on client and server; pick one
    • kneath prefers server-side
    • for server-side rendering, passing html back as one value in a json object allows for passing data back in other keys
  • html 5 history api
  • allows for much richer state management. See github’s new issues dashboard

Written by Erik

May 31, 2011 at 8:19 pm

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Notes from Neil Gershenfeld’s 5/24 talk at Twitter

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My mind was just blown by a talk from Neil Gershenfeld, director of the Bits and Atoms lab at MIT. His team created the fab lab. Here are  some notes

Written by Erik

May 24, 2011 at 12:45 pm

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Notes from Rob Pike’s 5/12 talk on Go at Twitter

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  • See golang.org for language documentation
  • W/in a factor of 2 slower than C/C++. Generally w/in 20% speed of c/c++ programs
  • Intrinsically safe
  • This talk has been presented before, so the slides may be online. see google io 2010 archive
  • check out article in Register about Go that quotes Odersky: “I like a lot of the design decisions they made in the language … Basically, I like all of them.”
  • built on 4 self-reinforcing principles: simple, ortho, succinct, safe
  • see axiom of choice in type theory
  • public/private hint in variable name is one of the best things about the language
  • see CSP tradition
  • uses a deterministic model, channels, for concurrency
  • the “go” keyword launches a go routine
  • “for { … ” declares an infinite loop
  • expressiveness comes from orthogonal composition of constructs
  • Go conceived while waiting for 45 min gcc compilation
  • Go app engine sdk is a complete installation vs building from source

Questions

How is the language intrinsically safe?

  • no stack overflows

Interoperability?

  • native swig support for C/C++ progs
  • no java interop

Exceptions?

  • no try/catch
  • uses panic/recover
  • function-level, not statement-level

Channel implementation?

  • not like erlang channels
  • passing channel over netchan is coming

Generics?

  • Core team has members that believe generics must and must-not be included

Upgrading?

  • gofix rewrites code
  • gofont pretty-prints/formats code

Inspirations?

  • Oberon
  • New Squeek
  • Didn’t cherry-pick features to build an ideal language, but they did include elements that helped them be productive

Written by Erik

May 12, 2011 at 11:24 am

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