Libraries Overview

Epsilon provides functional libraries organized into several packages:

Core Data Structures

• Data Structures - Immutable maps, sets, and collections
• JSON & YAML - Data serialization and parsing
• Cryptography - Hashing and checksums
• String Processing - Unicode-aware text operations

System Integration

• Networking - HTTP client/server and socket programming
• Threading - Concurrency primitives and thread pools
• Filesystem - File and directory operations

Design Philosophy

All libraries follow these principles:

• Immutable by default: Data structures don't modify in place
• Functional interfaces: Pure functions where possible
• Local nicknames: Clean integration with your code
• No external dependencies: Built on SBCL primitives only

Usage Pattern

(defpackage :my-app
  (:use :cl)
  (:local-nicknames
   (:map :epsilon.lib.map)
   (:json :epsilon.lib.json)
   (:http :epsilon.net.http)))

(in-package :my-app)

;; Use the libraries with clean syntax
(defun api-handler (request)
  (let ((data (map:make-map :status "ok" :timestamp (get-universal-time))))
    (http:respond request 200 (json:encode data))))