Build it, index a repo, ask a question.

# 1 · install the Rust toolchain (skip if you already have cargo)
brew install rustup-init && rustup-init -y          # or: curl https://sh.rustup.rs -sSf | sh

# 2 · clone & build — pure Rust, no Xcode / C toolchain, no libfuse, no protoc
git clone https://github.com/021flow/synafs && cd synafs
cargo build --release                                # Apple Silicon & Intel

# 3 · index a repo and ask — runs natively on macOS
./target/release/syna init
./target/release/syna index .
./target/release/syna query "reciprocal rank fusion" --top 3

# real semantic embeddings work on macOS — Metal is 3.8× faster than CPU
cargo build --release --features coderank-metal
SYNA_DEVICE=metal SYNA_EMBEDDER=coderank ./target/release/syna index .

# note: syna mount (FUSE) is Linux-only — every other surface runs here

git clone https://github.com/021flow/synafs && cd synafs
cargo build --release
cargo test                # 300 tests: RRF/BM25 + consistency/recovery + symbols + as-of/GC/diff + FUSE + web/gRPC + C ABI/CUSE

# index a repo, then query by meaning
syna init
syna index .
syna query "reciprocal rank fusion" --top 3 --lang rust
syna query --batch "where is auth checked?" "how are configs loaded?"  # N questions, one call
syna query "validate token" --rerank symbolgraph:callers   # call-graph rerank
syna query "login" --as-of HEAD~1                            # search code as it was then

# write path → reindex → consistency token; seal & inspect history
syna edit src/auth.rs --content "$(cat new.rs)"
syna commit -m "checkpoint"                                 # seal the working tree into a version
syna log
syna diff --symbol validate                                 # symbol-level diff across versions
syna symbols validate --relation callers                    # who calls it
syna gc                                              # reclaim chunks from unreachable versions

# surfaces
syna mount /mnt/repo                                       # FUSE: ls /mnt/repo/.syna/query/...
SYNA_TOKEN=secret syna serve --addr 127.0.0.1:5200         # HTTP API + gRPC-Web
syna grpc --addr 127.0.0.1:5201                           # native HTTP/2 gRPC
syna watch                                           # inotify auto-reindex (build --features watch)
sudo syna watch --fanotify                              # whole-mount VFS watch (build --features fanotify, root)
sudo syna dev                                         # /dev/synafs CUSE device (CAP_SYS_ADMIN)
syna bench                                            # throughput · p50/p99 latency · recall@k/MRR
syna usage                                            # MCP adoption health from .syna/mcp-usage.jsonl

# build with the local semantic embedder (pure-Rust candle)
cargo build --release --features coderank

# index and query with real embeddings (model auto-downloads to ~/.cache/synafs)
SYNA_EMBEDDER=coderank syna index <repo>
syna query "authenticate a user token"

cargo build --release
# register with Claude Code (use absolute paths)
claude mcp add synafs -- /ABS/PATH/SynaFS/target/release/syna-mcp /ABS/PATH/your-repo

{
  "mcpServers": {
    "synafs": {
      "command": "/ABS/PATH/SynaFS/target/release/syna-mcp",
      "args": ["/ABS/PATH/your-repo"]
    }
  }
}

# ~/.codex/config.toml  (or per-project .codex/config.toml)
[mcp_servers.synafs]
command = "/ABS/PATH/SynaFS/target/release/syna-mcp"
args = ["/ABS/PATH/your-repo"]
# for semantic results from a coderank-built binary:
env = { SYNA_EMBEDDER = "coderank" }

# or wire it inline for a single run (no config file)
codex exec \
  -c 'mcp_servers.synafs.command="/ABS/PATH/SynaFS/target/release/syna-mcp"' \
  -c 'mcp_servers.synafs.args=["/ABS/PATH/your-repo"]' \
  "where is reciprocal rank fusion implemented?"

// ~/.gemini/settings.json  (or per-project .gemini/settings.json)
{
  "mcpServers": {
    "synafs": {
      "command": "/ABS/PATH/SynaFS/target/release/syna-mcp",
      "args": ["/ABS/PATH/your-repo"],
      "env": { "SYNA_EMBEDDER": "coderank" }
    }
  }
}

# 1 · build the local semantic embedder once
cargo build --release --features coderank

# 2 · index with REAL embeddings — this is the retrieval-quality path agents ride on
SYNA_EMBEDDER=coderank syna index /ABS/PATH/your-repo

# 3 · keep the index fresh as the agent edits (inotify auto-reindex)
syna watch                                  # build --features watch

# 4 · ask several independent questions in ONE call, not one turn each
syna query --batch "where is auth checked?" "how are configs loaded?"

# then audit what your agent sessions actually did
syna usage                                  # adoption health from .syna/mcp-usage.jsonl