Fragmented Keys — Elixir library for composite cache key management and invalidation via independently versioned tags.

fragmented-keys-ex/
 lib/                            # Application source → [lib.md](lib.md)
    fragmented_keys/            #   Core modules
       cache_handler/          #     Backend implementations (Memory, Redis)
       tag/                    #     Tag types (Standard, Constant)
       cache_handler.ex        #     CacheHandler protocol definition
       configuration.ex        #     Global config via :persistent_term
       key.ex                  #     Composite cache key builder
       key_ring.ex             #     Key template factory
       tag.ex                  #     Unified tag operations interface
    fragmented_keys.ex          #   Top-level module and docs
 test/                           # Test suites
    fragmented_keys_test.exs    #   Main test file
    test_helper.exs             #   Test bootstrap
 docs/                           # Documentation
    arch/                       #   Architecture detail docs
       cache-handler.md        #     Cache handler protocol details
       invalidation.md         #     Key invalidation strategy details
    layout/                     #   Layout detail docs
       lib.md                  #     lib/ detailed breakdown
    PROJ-ARCH.md                #   Architecture overview
    PROJ-ARCH.summary.md        #   Architecture quick reference
    PROJ-LAYOUT.md              #   This file
    PROJ-LAYOUT.summary.md      #   Layout quick reference
 .claude/                        # Claude Code configuration
    settings.local.json
 .formatter.exs                  # Mix formatter config
 .gitignore                      # Git ignore rules
 .tool-versions                  # asdf — erlang 28.4, elixir 1.19.5, nodejs 25.8.1
 LICENSE                         # MIT license
 mix.exs                         # Project definition and dependencies
 mix.lock                        # Locked dependency versions
 README.md                       # Project entry point

Key Files Requiring Setup

FileAction
.tool-versionsInstall runtimes via asdf install
mix.exs:redix is optional — add if Redis backend needed