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Basic Syntax

Kahuna Script is inspired by Lua, Ruby, Bash and PL/pgSQL. Its syntax is easy to understand because of its similarity to widely used languages, making it accessible for developers familiar with scripting or database logic.

A "Hello World" in Kahuna Script would look like this:

return 'Hello World'

A slightly more useful example:

begin
 let current_leader = get `election/leader`
 if rev(current_leader) == 0 then
   set `election/leader` "node-A"
 else
   throw "election failed"
 end
 commit
end

Variables​

In scripts, variables have local and temporary scope, meaning they exist only for the duration of the script’s execution.

Variables can be used to retrieve values from the key/value store and also to hold modified values that can later be written back.

Example:

let current_limits = get "user:123:limits"
let current_limits = current_limits - 1
set "user:123:limits" current_limits

This pattern, read, modify, write, is common in Kahuna Script and helps encapsulate logic close to the data while avoiding multiple round-trips.

Reserved Words and Escaping Identifiers​

Some identifiers are reserved words and cannot be used as constant or variable names. It’s recommended to escape key names using backticks ` or quotes ' ' or " " to avoid conflicts. For example:

set election_leader "node-A"
set `election_leader` "node-A"
set "election_leader" "node-A"

By escaping keys, you can use all kinds of characters and symbols that might not otherwise be allowed. For example:

set `end` "some value" # reserved word end
set `user@domain.com` "active" # symbols
set "config:env/prod#1" true # symbols
set "🔥special-key$" 123 # emojis

This allows for greater flexibility in naming keys, especially when working with external systems, user-generated IDs, or complex naming conventions.

Whitespace and Line Endings​

Whitespace characters such as spaces and tabs are generally ignored in Kahuna Script code, except when they appear in strings:

let my_range = 1..10 for i in my_range do if i == 5 then return i end end throw "needle wasn't found"

The previous script is equivalent to:

let my_range = 1..10
for i in my_range do
    if i == 5 then
        return i
    end
end

throw "needle wasn't found"