peterc

How to set up a basic Sinatra + React webapp in 2025

Let's say you want to use Ruby for the backend of a basic webapp but React on the frontend. Here's how.

(Note: All tested on January 13, 2025 with Ruby 3.3, Sinatra 4.1.1, and React 18.3. Configs may change over time.)

First, create the app folder and set up Sinatra:

mkdir my-sinatra-react-app

peterc

import Metal

// Inline Metal shader code
let shaderSource = """
kernel void multiply(const device float* a [[ buffer(0) ]],
                     const device float* b [[ buffer(1) ]],
                     device float* result [[ buffer(2) ]],
                     uint id [[ thread_position_in_grid ]]) {
    result[id] = a[id] * b[id];

peterc

#!/bin/bash

# Check if a repository URL was provided
if [ $# -ne 1 ]; then
    echo "Usage: $0 <repository-url>"
    exit 1
fi

REPO_URL=$1

peterc

WITH RECURSIVE
  xaxis(x) AS (
    SELECT -2.0
    UNION ALL
    SELECT x + 0.05 FROM xaxis WHERE x < 1.2
  ),
  yaxis(y) AS (
    SELECT -1.0
    UNION ALL
    SELECT y + 0.1 FROM yaxis WHERE y < 1.0

peterc

A test of the technique illustrated by Simon Willison at https://til.simonwillison.net/llms/docs-from-tests

JSON Library Usage Documentation

Basic Usage

Parsing JSON

# Parse JSON string into Ruby objects

peterc

To compile:

as -o hello.o hello.s
ld -o hello hello.o -lSystem -syslibroot `xcrun -sdk macosx --show-sdk-path` -e _main -arch arm64

./hello

peterc

Seems to work, but I'm not an expert with this stuff, so YMMV.

peterc

require 'http'
require 'json'

class GroqClient
  def initialize(api_key: nil, api_url: "https://api.groq.com/openai/v1/chat/completions", model: "mixtral-8x7b-32768")
    @api_key = api_key || ENV['GROQ_API_KEY']
    @api_url = api_url
    @model = model
  end

peterc

put.your.domain.here {

  @local {
    file
    not path /
  }

  log {
    output file /var/log/caddy/mastodon.log
  }

peterc

# Example of using SQLite VSS with OpenAI's text embedding API
# from Ruby.

# Note: Install/bundle the sqlite3, sqlite_vss, and ruby-openai gems first
# OPENAI_API_KEY must also be set in the environment
# Other embeddings can be used, but this is the easiest for a quick demo

# More on the topic at
# https://observablehq.com/@asg017/introducing-sqlite-vss
# https://observablehq.com/@asg017/making-sqlite-extension-gem-installable