Cryptaa

crypta

(n.) an underground vault or chamber, especially one beneath a church that is used as a burial place.

Or an offline-first blazing fast & secure note taking application. Check the latest development version at: https://cryptaa.pages.dev. Note that the name is "Cryptaa", with two 'a's instead of one. The application has a first version. However, I started from scratch here to explore some better ideas.

Motivations and Features

For a note-taking application, I wanted these attributes:

• Manual data encryption & decryption: I'm not overly paranoid about data security/data breaching, but sometimes, I do want my data to be stored securely (login credentials or credit card numbers). If I really need the functionality, I can encrypt the text on another website, then paste it to the application. It is not the best UX, however.
• Speed: it should feel fast/snappy enough (if you definitely want a number, maybe it is less than 100ms).
• Many devices (at least mobile/Android and desktop/Linux) data synchronization: I have an Android phone, and two Linux desktops, and want to have the same data between them.
• Web version: I don't like installing another application whether it's on my phone nor my computer.

It surprised me that I couldn't find anything that check all the boxes. Some check more than the others, but in the end, all of them are inadequate and served as the inspiration for Cryptaa. ^{Or NIH syndrome kicked in, and I wanted to use that chance to polish my skills/play around with new technologies.}

How It Works

Cryptaa uses Triplit under the hood. Triplit runs in your browser (persisting to IndexedDB), and can be run within an independent server (persisting to SQLite) as well.

sequenceDiagram
    actor u as User
    participant c1 as Client 1 (Mobile)
    participant s as Server
    participant c2 as Client 2 (Desktop)

    u ->> c1: create notes
    c1 ->> c1: store the data
    c1 ->> s: send data
    s ->> s: store the data
    s ->> c2: send data

Development

• Make sure that you have node and npm ready:

node --version
# v18.18.2
npm --version
# 9.8.1

• Install dependencies:

npm install

• Start the development client:

npm run dev

• Start the synchronization server:

npm run server
# or
npx triplit dev

Client Deployment

• Build static files:

yarn build

The built files should be available in a folder named build/. You are free to copy this somewhere else and serve it as a static website using a web server like Nginx or Caddy.

• Preview (see how the built files work):

npm run preview

Or you can move to the folder and try serving it yourself:

# cd build
python -m http.server

Server Deployment

• Clone the repository on the machine that you want to deploy the server. Make sure that npm is ready and the dependencies are installed (look at the section for "Development").

• Set your environment variables at .env:

TRIPLIT_JWT_SECRET=super-secret
TRIPLIT_PROJECT_ID=cryptaa-server

• Start the server:

# to run the server at port 5432
npm run server
# or specify another port
PORT=8888 npm run server

• Note the service token down somewhere as you'll need them for synchronization between different clients:

Service Token
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ4LXRyaXBsaXQtdG9rZW4[...]

• A good security practice is to "hide" the port from public access (does not allow access to http://<your-ip>:5432), and use a HTTPS reverse proxy to it (allow access to https://cryptaa-server.<your-domain>). Feel free to use Nginx or Caddy or anything that you're comfortable with.

• Demo server's credentials:

URL: https://cryptaa-server-demo.nguyenhuythanh.com
Token: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ4LXRyaXBsaXQtdG9rZW4tdHlwZSI6InNlY3JldCIsIngtdHJpcGxpdC1wcm9qZWN0LWlkIjoiY3J5cHRhYS1zZXJ2ZXIifQ.IDJB0XN3CjpBbWJxyGpHKbPU6rTQkndsFZYF2h4WEto

Miscellanies

Thanks to JetBrains for granting this project's previous version an Open Source License.