Two Faces.
One Truth.

// The simplest honest program.
func main() do
  println("Hello, Sovereign World.")
end

// Verbose? Never. Janus is as terse as you want it to be.

func clamp(x: i64, lo: i64, hi: i64) -> i64 = match x { _ if x < lo => lo, _ if x > hi => hi, _ => x }

func is_prime(n: i64) -> bool = n > 1 and for 2..isqrt(n)+1 do |i| n % i != 0 end

func fizzbuzz(n: i64) -> string = match (n%3, n%5) { (0,0) => "FizzBuzz", (0,_) => "Fizz", (_,0) => "Buzz", _ => itoa(n) }

// Same language. Same compiler. Your call.

trait Drawable {
  func draw(self) -> i32
}

struct Circle { radius: i32 }

impl Drawable for Circle {
  func draw(self) -> i32 do
    return self.radius * 2
  end
}

// Dynamic dispatch. Cost is visible.
func render(d: &dyn Drawable) -> i32 do
  return d.draw()
end

func parse_port(s: string) -> i32 ! ParseError do
  let n = to_int(s) catch |e| do
    fail ParseError.InvalidNumber
  end
  if n < 0 or n > 65535 do
    fail ParseError.OutOfRange
  end
  return n
end

func fetch_all(urls: []string) do
  nursery |n| do
    for url in urls do
      n.spawn(async fetch(url))
    end
  end // All tasks complete or cancel here.
end

const Ed25519 = std.crypto.sign.Ed25519;

pub const SoulKey = struct {
    seed:   [32]u8,
    public: [32]u8,

    pub fn sign(self: *const SoulKey, msg: []const u8) [64]u8 do
        const kp = Ed25519.KeyPair
            .generateDeterministic(self.seed) catch return .{0} ** 64;
        return kp.sign(msg, null).toBytes();
    end
}; // Zig types. Janus syntax. One binary.

// Sovereign package manifest.
project {
  name "myservice"
  version "1.0.0"
  profile "service"
}

dependencies {
  crypto "^2.1.0" // Verified supply chain
}

// Ed25519 signed. BLAKE3 content-addressed.
// Publish: janus pkg publish --key id.key