PLDN Solid Kick-Off

You can choose where you store
every single piece of data you produce.

You can grant apps and people access
to very specific parts of your data.

Separating app and storage competition
drives permissionless innovation.

The traditional way of building apps
does not work well with decentralization.

Building apps over decentralized data
requires different app techniques.

Solid is an ecosystem of data and apps
that work seamlessly together.

• data pods
  • profile
  • photos
  • comments
  • likes
  • …
• applications
  • photo album
  • meeting invites
  • document collaboration
  • …
• standards
  • HTTP
  • URL
  • RDF
  • LDP
  • LDN
  • …

The Solid server and several apps exist
and are usable for developers.

• Solid server
  • store your data online with access control
  • free storage at solid.community and inrupt.net
• apps
  • data browser
  • contacts
  • photos
  • meeting organizer
  • …
• libraries
  • authentication
  • data processing
  • …

The Solid ecosystem is backed by Inrupt,
which aims to accelerate development.

• open up the ecosystem for all
• maintain common building blocks as open source
• create tooling for developers
• offer services and apps

Interoperability challenges in Solid
are solved through Linked Data in RDF.

• If we all store our own data,
  how do we connect it to others’ data?
• How can apps share data,
  without too many prior agreements?
• How do we integrate data
  from multiple data pods?

With JSON-LD, every piece of data
can link to any other piece of data.

{
  "@context":  "https://www.w3.org/ns/activitystreams",
  "id":        "#ruben-likes-pldn-2019",
  "type":      "Like",
  "actor":     "https://ruben.verborgh.org/profile/#me",
  "object":    "http://www.pilod.nl/wiki/PLDN-Solid_Kick-Off#this",
  "published": "2019-04-08T20:00:00Z"
}

Data shapes and their semantics
enable layered compatibility.

{
  "@context":  "https://www.w3.org/ns/activitystreams",
  "id":        "#ruben-likes-pldn-2019",
  "type":      "Like",
  "actor":     "https://ruben.verborgh.org/profile/#me",
  "object":    "http://www.pilod.nl/wiki/PLDN-Solid_Kick-Off#this",
  "published": "2019-04-08T20:00:00Z"
}

Different source data
can be concatenated.

{
  "@context":  "https://www.w3.org/ns/activitystreams",
  "@graph": [{
    "type":      "Like",
    "actor":     "https://ruben.verborgh.org/profile/#me",
    "object":    "http://www.pilod.nl/wiki/PLDN-Solid_Kick-Off#this",
    "published": "2019-04-08T20:00:00Z"
  },{
    "type":      "Like",
    "actor":     "https://example.org/people/pieter#me",
    "object":    "http://www.pilod.nl/wiki/PLDN-Solid_Kick-Off#this",
    "published": "2019-04-08T20:05:00Z"
  }]
}

You’re using Semantic Web technology?
Developers have never wanted it.

• Today’s new generation of front-end developers
  are not burdened by the inheritance of the past.
  • XML
  • Java
  • Big Data
  • …
• They just want to build cool things.
  • Thanks to Solid, they don’t need to harvest data.
• They like Linked Data when show it to them!

Can developers build Linked Data apps
without exposure to raw RDF?

• We could create object-oriented abstractions
  for specific concepts and domains.
  • Forcing data into specific shapes
    hides the benefits of Linked Data.
• We need to create new developer experiences
  that make programming with Linked Data fun.
  • How to get them to think in graphs?

LDflex is a domain-specific language
for traversing Linked Data graphs.

const person = node('https://me.example.org/#me')

person.label
person.friends.firstName

const label = await person.label

for await (const name of person.friends.firstName)
  console.log(name)

LDflex uses SPARQL under the hood
and invokes a client-side query engine.

const person = node('https://me.example.org/#me')
const query = await person.friends.firstName.sparql

SELECT ?firstName WHERE {
  <https://me.example.org/#me> foaf:knows ?v0.
  ?v0 foaf:givenName ?firstName.
}

<LoggedIn>
  <p>Welcome, <Value src="user.firstName"/></p>
  <Image src="user.image" defaultSrc="profile.svg"/>
  <ul>
    <li><Link href="user.inbox">Your inbox</Link></li>
    <li><Link href="user.homepage">Your homepage</Link></li>
  </ul>
  <h2>Your friends</h2>
  <List src="user.friends.firstName"/>
</LoggedIn>

Join us at solid.inrupt.com!