Most iOS AI apps lose their memory the moment the user closes them. Wax fixes that — giving your agents persistent, searchable, private memory that lives entirely on-device in a single portable file.
import Wax
import WaxVectorSearchMiniLM
let memory = try await MemoryOrchestrator.openMiniLM(
at: .documentsDirectory.appending(path: "agent.wax")
)
// Store a memory
try await memory.remember("User prefers concise answers and hates bullet points.")
// Retrieve the most relevant context — semantically
let context = try await memory.recall(query: "communication preferences")Building AI agents on Apple platforms means juggling Core Data for persistence, FAISS or Annoy for vector search, and a tokenizer for context budgets — none of which talk to each other. Or you spin up Chroma or Pinecone and suddenly your app has a server dependency, network calls, and a privacy story you can't tell users.
Wax packages all of it into one self-contained file:
| Capability | Without Wax | With Wax |
|---|---|---|
| Document storage | Core Data / SQLite | ✅ Built-in |
| Semantic search | External FAISS / Annoy | ✅ Built-in (HNSW) |
| Full-text search | Another index | ✅ Built-in (BM25) |
| Token budgeting | Manual | ✅ Automatic |
| Crash safety | You figure it out | ✅ WAL + dual headers |
| Server required | Often | ✅ Never |
- Hybrid retrieval — BM25 keyword search fused with HNSW vector similarity. Gets the right memory, even when wording differs.
- On-device embeddings — Powered by MiniLM, running locally. No API calls, no latency, no cost.
- Metal acceleration — Embedding and search use Apple Silicon GPU when available.
- Token budgets — Set a hard limit. Wax automatically trims and compresses context to fit, every time.
- Tiered surrogates — Store full text, a gist, or a micro-summary. Trade recall for speed at query time.
- Single portable file — The whole memory store is one
.waxfile. Back it up, sync it, move it. - Crash-safe by design — Append-only format with write-ahead logging and dual headers. No corruption on unexpected exits.
- Swift 6 concurrency — Fully
async/awaitnative withSendableconformances throughout.
Swift Package Manager
// Package.swift
dependencies: [
.package(url: "https://github.com/christopherkarani/Wax.git", from: "0.1.8")
],
targets: [
.target(
name: "MyApp",
dependencies: [
.product(name: "Wax", package: "Wax"),
.product(name: "WaxVectorSearchMiniLM", package: "Wax")
]
)
]Or in Xcode: File → Add Package Dependencies → paste the repo URL.
npx -y waxmcp@latest mcp install --scope userAfter installing the MCP server, add this to your CLAUDE.md so Claude Code uses Wax as its memory:
CLAUDE.md snippet (click to expand)
## Rules
1. **Session start** — call `wax_handoff_latest` to resume prior context
2. **Before answering** — call `wax_recall` to check what you already know. Always try this first.
3. **When you learn something durable** — call `wax_remember`. Worth storing: user preferences, project decisions, architectural patterns, conventions, people/roles. Not worth storing: transient debugging, one-off commands.
4. **When corrected** — call `wax_forget` with what changed (e.g. "we don't use Redux anymore")
5. **Session end** — call `wax_handoff` with summary + pending tasks
## Tools
| Tool | When |
|------|------|
| `wax_remember` | User states a preference, makes a decision, or you learn a stable pattern. `project` to scope. |
| `wax_recall` | Before answering anything that might have prior context. Use `graph: true` for relationship-aware search. |
| `wax_forget` | User corrects you or facts become outdated. Natural language or `fact_id`. |
| `wax_context` | Need the full picture of a specific entity (person, project, library). |
| `wax_reflect` | Audit what you know — entity counts, top predicates, memory health. |
| `wax_handoff` | Session ending. Pass `pending_tasks` array for continuity. |
| `wax_handoff_latest` | Session starting. Loads last handoff. |import Wax
import WaxVectorSearchMiniLM
// 1. Open (or create) a memory store
let memory = try await MemoryOrchestrator.openMiniLM(
at: .documentsDirectory.appending(path: "myagent.wax")
)
// 2. Store memories
try await memory.remember("The user's name is Alex and they live in Toronto.")
try await memory.remember("Alex dislikes formal language. Keep responses casual.")
try await memory.remember("Alex is building a habit tracker in SwiftUI.")
// 3. Retrieve relevant context for a prompt
let context = try await memory.recall(query: "how should I address the user?")
print(context.items.map(\.text))- Conversational agents that remember preferences, history, and facts across sessions
- Note-taking apps with semantic search ("find everything I wrote about WWDC")
- Photo & video apps that index captions and transcripts for natural-language lookup
- Personal assistants that learn user habits without sending data off-device
- RAG pipelines built entirely on-device for sensitive or offline-first applications
| Minimum | |
|---|---|
| Swift | 6.2 |
| iOS | 17.0 |
| macOS | 14.0 |
| Xcode | 16.0 |
Apple Silicon recommended for GPU-accelerated embedding. Intel Macs fall back to CPU seamlessly.
| Wax | ChromaDB | Pinecone | Core Data + FAISS | |
|---|---|---|---|---|
| On-device | ✅ | ❌ | ❌ | ✅ |
| No server | ✅ | ❌ | ❌ | ✅ |
| Hybrid search | ✅ | ✅ | ✅ | Manual |
| Token budgeting | ✅ | ❌ | ❌ | ❌ |
| Single file | ✅ | ❌ | ❌ | ❌ |
| Swift-native API | ✅ | ❌ | ❌ | Partial |
| Privacy (data stays on device) | ✅ | ❌ | ❌ | ✅ |
- CloudKit sync (opt-in, encrypted)
- iCloud Drive
.waxdocument support - Memory clustering and deduplication
- Quantized embedding models for smaller footprint
- Instruments template for memory profiling
Issues and PRs are welcome. If you're building something with Wax, open a Discussion — would love to see what you're working on.
Apache 2.0 © Christopher Karani
