indexio
[release]
[npm]
[PyPI]
[license]
indexio is a code search engine for AI coding agents. It indexes all the repositories of an
organization one time. It answers a query in milliseconds. It gives the index to agents as
a tool through the Model Context Protocol (MCP) and through an HTTP API.
indexio is one binary, written in Rust. It does not need a database or an external
service. The index is a set of files in one data directory. You can copy that directory to
another machine.
Let your agent install it
Paste the block below to Claude Code, Cursor, Codex or any coding agent that can run
shell commands. It installs indexio, indexes your code, registers the MCP server and
verifies the result. Replace ~/code with the folder that holds your repositories.
What the agent gets afterwards: code_search, code_grep, find_symbol, who_calls,
file_outline, read_span, impact_of_symbol, impact_of_diff and recall as tools,
answered from the index in milliseconds. The tools table describes each one.
Install
Pick one. Each one gives you the indexio command.
The scripts and the npm package download the binary of the latest
release for your OS and CPU and
check its SHA-256. The pip wheels carry the binary inside them, one wheel per platform.
The pip package is called indexio-cli because indexio on PyPI belongs to an unrelated
project; the command it installs is indexio. The container image works with no install
at all: see Deploy with Docker. git must be on the PATH. No service, no database and no model download
is necessary.
Upgrade
Run the same install command again. The index in ~/.indexio stays, and you do not
index again.
Then do two more steps:
- Run
indexio hook install. It adds the hooks that the new version brings and repairs the
others. It keeps your own hooks.
- Restart your agent sessions. A running session keeps its indexio server until it
restarts.
Running sessions do not stop you from upgrading:
- The two scripts replace the binary while sessions use it. On Windows,
install.ps1 moves
the running indexio.exe to indexio.old.exe and copies the new one in.
- On Windows, npm and pip try to overwrite the binary in place, and Windows does not allow
that while it runs. Close your agent sessions first, or use the script.
- Sessions that still run the old version can read an index that the new version wrote.
- The first new server does its one-time work in the background: it embeds files that have
no vectors and it writes session cards. Calls are not blocked.
Quick start
Three commands. The third one is only for Claude Code.
Then restart Claude Code. Its sessions now have the indexio tools. Two optional commands
make the savings larger:
indexio stats shows what is indexed. indexio usage shows the tokens the index served
against what the built-in tools would have returned.
All data goes into one directory: --data-dir, $INDEXIO_DATA_DIR, or ~/.indexio.
Contents
- Let your agent install it
- What indexio does
- Add sources
- Keep the index current
- Embeddings
- What is never indexed
- Secure the HTTP API
- Team indexing: live worktree overlays
- Enterprise setup
- Use indexio with Claude Code
- Token savings, measured
- Impact analysis
- Use indexio from other tools
- Command reference
- Environment variables
- Deploy with Docker
- Architecture
- Measured performance
- Limits
- Development and releases
What indexio does
indexio answers three kinds of question about the code of an organization.
indexio also knows the definitions and the call graph of the code. It can tell you where a
symbol is defined, who calls it, and what breaks if you change it.
Add sources
Each add indexes the source immediately and builds the semantic plane.
Search:
Serve the index to agents:
indexio remembers each source in <data-dir>/sources.json. indexio sources lists the
sources and the registered repositories. indexio remove <source> forgets a source.
Useful flags for add: --limit 20 (trial run on a large organization), --include-forks,
--include-archived, --full-clone, --dest DIR (where remote clones go), --no-embed,
--exclude PATH, --pdf-text.
Folders with repositories and other files. A folder often holds git repositories and
files that are not in any repository: notes, specs, exports, PDFs. indexio add indexes
each repository as a repository, and the other files as one more repository with the
folder's name:
- Text files are indexed by contents, up to the size limit (256 KiB for text, 4 MiB for code).
- Documents (PDF, Word, Excel, PowerPoint, OpenDocument, RTF, EPUB) and text files over the
limit are indexed by name only.
list_files and a search for words of the name find them.
read_span on one says that its contents are not indexed; read the file itself. The hooks
let a Read of such a file through.
--pdf-text indexes the text layer of these PDFs instead of their name. A PDF that was
exported from a document (Word, Google Docs, a browser) has one, so a search finds words
inside it. A scanned PDF has no text layer and keeps its name-only entry: indexio does
no OCR. The extracted text has the text size limit. A PDF over 64 MiB, or one that
takes longer than 20 seconds to read, keeps its name-only entry. The option is
remembered with the source.
- Images, media, archives and other binary files are not indexed.
--exclude PATH (repeatable, relative to the folder) keeps a folder out: it is not a
repository and its files are not indexed. Excludes are remembered with the source and
accumulate when you run add again.
- A folder that is registered on its own is not indexed a second time.
Credentials. indexio reads credentials from the environment only: GITHUB_TOKEN (or
GH_TOKEN) and AZDO_TOKEN (or AZURE_DEVOPS_EXT_PAT, SYSTEM_ACCESSTOKEN). It sends
them to the listing APIs and to git as an authorization header. It never puts them in a
clone URL, in a log, or in .git/config. Public repositories do not need a token.
Keep the index current
Run indexio sync from cron or a timer, for example every 15 minutes. Each run is
incremental:
- New repositories are cloned.
- Changed git repositories are delta-indexed by commit.
- Changed plain folders are delta-indexed by content hash.
- New and changed chunks are embedded. All other chunks are cache hits.
A folder tree of 156 repositories and 17,530 files syncs as a no-op in 11 s.
A running indexio mcp server does more on its own:
- It watches the repository the session works in. It re-indexes the working tree before
each call when files changed. Uncommitted and untracked edits are searchable at once;
their embeddings follow on a background thread within a few hundred milliseconds.
- Every 10 minutes it probes the other repositories for a moved HEAD and re-indexes the
ones that moved, and re-indexes changed plain folders by content (after the first pass,
an unchanged file costs one stat).
- A session that starts before its folder is registered adopts the repository within one
minute of
indexio add. No restart is necessary.
- A session whose checkout is not registered but sits beside three or more registered
repositories adds it on its own (a git repository or a plain project folder of up to
20,000 files, never a folder that holds repositories). Set
INDEXIO_NO_AUTO_ADD, or
create <data_dir>/auto-add-skip, to turn this off.
- An answer from
read_span, code_grep, code_search or file_outline that is
identical to one this session got in the last 20 minutes comes back as a one-line
note. Sending the same call again returns the full text, and a compaction or /clear
resets this.
Embeddings
The built-in model
The default embedder is Random Indexing (rindex). It is a semantic model that indexio
builds in-process from your own code, on the CPU, in one streaming pass. It needs no
training infrastructure, no download and no GPU. It learns the vocabulary of your
organization: internal service names, code names and APIs that no pretrained model knows.
Each new chunk is an incremental update, so indexio sync stays cheap.
Measured on 20 hard concept queries (bench/): hybrid recall@5 is 60 % and MRR is 0.397.
Lexical search alone gives 5 % and 0.050 on the same queries.
An optional neural endpoint
For maximum retrieval quality, point indexio at any OpenAI-compatible embeddings endpoint,
for example Qwen3-Embedding on vLLM or TEI. The two model namespaces coexist.
Embeddings are content-addressed by (chunk hash, model id). Two repositories that share a
file share its embedding. Duplicate chunks across an organization cost nothing extra.
An optional reranker
Add a reranker endpoint, for example Qwen3-Reranker on TEI or vLLM. indexio uses it when a
query asks for it: indexio search --mode hybrid --rerank, rerank=1 over HTTP, or
rerank: true over MCP. Without an endpoint, --rerank has no effect.
What is never indexed
- Files without a known code, document, configuration, script or data extension, such as
databases, images, archives and compiled output.
- Binary content: a NUL byte in the first 8 KiB skips the file. Files over 4 MiB, and
text files over 256 KiB. In a plain folder, these files and documents (PDF, Office) are
indexed by name only (see Add sources).
- Build output, dependency and cache folders (
node_modules, target, dist, vendor,
any folder with a CACHEDIR.TAG), git-ignored files, hidden folders except the
configuration ones (.github, .cargo, .vscode, .devcontainer …), lock, minified
and source-map files.
- Credentials:
.env files, private keys and certificates (pem, key, p12, pfx,
jks, gpg …), .netrc, .npmrc, Terraform state. A credential file indexed by an
earlier version is removed by the next sync. .env.example and *.pub are kept.
The session transcripts and run logs that recall searches are redacted before they are
stored: values of secret-looking settings, passwords in URLs, API keys, bearer tokens,
JWTs and private-key blocks are replaced with <redacted>.
Secure the HTTP API
indexio serve binds to the loopback address by default.
For per-token repository access, use an ACL file:
With an ACL file:
- An unknown token gets HTTP 401.
- Hits outside the allowed patterns are removed from
/search, /symbol and /calls.
- Admin routes need a token with
allow: ["*"]. Other tokens get HTTP 403.
GET /health is always open.
Caution. A bind address other than loopback (--bind 0.0.0.0) is refused unless you
also set --auth-token, $INDEXIO_AUTH_TOKEN or --acl-file. The MCP server over stdio
runs as the local user and has no authentication by design. Put a network-facing MCP
server behind your own gateway.
Team indexing: live worktree overlays
indexio serve can layer every developer's uncommitted changes on top of the
shared index, so an agent answering you sees your working tree — edits,
untracked files, deletions — while everyone else keeps seeing the pushed
state. Nothing to install on the developer machine beyond a shell hook in
the agent harness: no indexio client.
How it works
- The server indexes the pushed repositories (the usual
add + sync).
- A
PreToolUse hook in the agent harness runs
integrations/claude-code/indexio-team-sync.sh before every indexio tool
call. The script diffs the working tree (untracked files included)
against the merge-base with the remote default branch and POSTs the patch
to /team/worktree.
- The server applies the patch into a small overlay shard keyed by the
caller's user name, layered over the base shards: changed paths shadow
the base index, deleted paths are hidden, everything else reads from the
shared index. Applying uses git plumbing on a scratch index — no
checkouts, no worktrees.
- A hash of the last accepted patch is kept on disk, so repeated calls
with unchanged work cost nothing. The hook prints nothing and always
exits 0: it can never block a tool call or pollute the agent's context.
Overlays expire after INDEXIO_TEAM_TTL_DAYS (default 7) without an update.
Server setup
Serve with an ACL file whose tokens carry a "user" — that name keys the
overlay:
A token without "user" works for reading but has no overlay (CI, above).
With a single --auth-token instead of an ACL file, clients pick their user
with the X-Indexio-User header.
Developer setup
setup claude --team-sync writes the hook script into the Claude config
dir and prints the PreToolUse entry for settings.json — matcher
mcp__indexio__.*, so the sync runs right before any indexio tool call.
With one shared token instead of per-user tokens, also set INDEXIO_USER
to the name to act as.
What is enforced server-side
- Credential paths are never accepted into an
overlay, and neither are patches over 32 MiB.
- ACL
allow patterns filter what each user reads — on the documents
themselves for MCP (rendered text cannot be un-shown), as hit-filtering
on the REST API.
- Overlay user names are constrained to
[A-Za-z0-9._@-], no leading dot,
so overlay state stays path-safe (SSO identities are usually emails).
Serving many developers at once
- The server reopens its index by itself when a
sync, reindex or
compaction writes new shards: the new engine is opened and warmed off the
request path and swapped in, so nobody calls /admin/reload and no
request waits for it. The semantic plane is parsed at startup and after
each embed.
- Every request runs on a worker pool, and small lookups stay off the shared
parallel pool, so a
find_symbol or read_span answers in about a
millisecond while other users run broad greps and hybrid searches.
- A developer's view is their overlay layered over the one shared index:
about 1 MB per developer, opened in milliseconds, and opened in the
background right after each upload.
- One content cache serves everyone:
INDEXIO_CONTENT_CACHE_MB (default
1024) holds decompressed files for every user's searches.
- Responses are gzipped for clients that accept it; the hook uploads large
patches gzipped.
- A session's own repo comes first in results and is the default of
read_span and file_outline, as in a local session: the repo the client
names in an X-Indexio-Repo header (a name or the origin URL), else the
repo the developer last synced edits for.
impact_of_diff without a diff maps the developer's synced worktree
against its merge-base.
Team limits
- Overlays are lexical planes. Vector search ranks the base content; edits
to tracked files surface through every tool, while brand-new untracked
files and deletions are visible to the lexical, symbol and outline tools.
- The base must be a commit the server has (the merge-base with
origin/HEAD, else origin/main, origin/master, or the upstream
branch), otherwise the upload is refused with HTTP 409 and retried on the
next call. The server fetches the origin itself, rate-limited to once a
minute.
- The hook ships tuned for Claude Code; the
PreToolUse contract is the
one other harnesses are converging on, but only Claude Code is tested.
Enterprise setup
Everything above runs on one machine. The same binary scales to a team
server or an organization-wide deployment; the moving parts are the
network edge and authentication.
Inside the network (LAN / VPN)
The simplest topology: one indexio server on an internal host, bound to a
private interface; TLS optional on a trusted network.
Developers aim their team-sync hook at it with INDEXIO_URL +
INDEXIO_TOKEN. Start with an ACL file; move to SSO (below) when
handing out tokens becomes the chore.
Facing the internet
The server speaks plain HTTP and refuses to bind wide without
credentials, so put it behind a reverse proxy that terminates TLS and
forwards to the loopback port. A minimal Caddy site:
Then serve with SSO rather than static tokens: a short-lived identity
token beats a long-lived bearer on a laptop.
SSO with an OIDC provider (Entra ID, Google, Keycloak)
--oidc-issuer + --oidc-audience replace the static-token modes. The
server discovers the provider at
<issuer>/.well-known/openid-configuration, caches its JWKS, and
validates every bearer token (RS256, issuer, audience, expiry) before
looking the identity up — fail closed:
- The identity is the token's
email claim (else sub). An identity
not present in users.json gets HTTP 401: provisioning is your
existing directory, mirrored into this file by hand or by a sync job.
allow works exactly like the token ACL; /admin still needs *.
"user" sets the team-overlay name — without it the email is used.
- IdP specifics. Entra ID: an app registration with an exposed API; the
audience is the Application ID URI. Google Workspace: a Web
application OAuth client; the audience is the client ID. Keycloak: a
confidential client in your realm; the audience is the client ID and
the issuer
https://<host>/realms/<realm>.
- Signing keys rotate without a restart: an unknown
kid refetches the
JWKS on demand.
- OIDC mode supersedes
--auth-token/INDEXIO_AUTH_TOKEN; leave them
unset. --oidc-audience requires --oidc-issuer.
Try it: Google Workspace in ten minutes
The exact flow, verified end-to-end against a live server on 2026-09-27.
-
Google Cloud console: create a project (indexio-pilot, say).
-
APIs & Services → OAuth consent screen: External; app name
indexio pilot; scopes openid and email; add your own Google
account under Test users — while the app is in "Testing", only
test users can consent. This is the step everyone forgets.
-
Credentials → Create OAuth client ID → Web application: add
authorized redirect URI https://developers.google.com/oauthplayground.
-
Mint a real ID token at
https://developers.google.com/oauthplayground: gear icon → "Use your
own OAuth credentials" → paste the client ID and secret → scope
openid email → Authorize APIs → consent → Exchange
authorization code for tokens → copy the id_token.
-
Serve with the client ID as the audience and your email in the users
file:
-
Smoke test from anywhere:
Beyond the playground, anything that can run the OAuth consent flow can
produce a bearer the server accepts: an IDE plugin, a small login page
in front of the server, or a CI job.
GitHub
GitHub is not a general OIDC provider for your own API, but two
patterns cover it:
-
GitHub Actions → indexio is OIDC already. A job with
permissions: id-token: write requests a JWT (issuer
https://token.actions.githubusercontent.com, audience of your
choosing) and hands it to indexio clients as the bearer token. The
server validates it like any OIDC token:
CI machines hold no static token, and the allow list in users.json
scopes what each workflow may read.
-
Humans with GitHub accounts. Put an OIDC gateway in front
(oauth2-proxy configured for GitHub) and keep ACL-file tokens between
gateway and indexio, or move human access to Entra ID / Google, where
directory-backed provisioning belongs.
Humans vs agents
Keep the two populations on different credentials: humans on SSO
short-lived tokens, agents and CI on ACL-file tokens scoped to the
repositories they touch (allow: ["payments-*"]). Revoking a human is
disabling their directory account; revoking an agent is deleting one
line of the ACL file.
Use indexio with Claude Code
indexio speaks MCP over stdio. This is the native tool interface of Claude Code, of the
Claude Agent SDK and of most coding agents.
Register the server
Do one of these:
-
Run indexio setup claude. It runs claude mcp add for this binary and data directory,
and it prints the guidance block for your CLAUDE.md. Add --claude-md ~/.claude/CLAUDE.md
to append the block.
-
Run claude mcp add indexio -- /usr/local/bin/indexio mcp --data-dir /var/lib/indexio.
-
Commit a .mcp.json to the project:
Install the hooks
This writes five Claude Code hooks into ~/.claude/settings.json:
The Bash hook also routes scripts and builds (python, node, npm, pytest, go,
make …) through indexio run, which keeps a long output out of the context: the first
lines, the error lines and the last lines are returned with a runs:<repo>/<log> pointer,
and the full output stays searchable for 30 days.
To keep a shell command from being rewritten, add # raw to it or set INDEXIO_RAW=1.
The tools
The server tells Claude which built-in tool each indexio tool replaces, and which
repositories are indexed. Claude then routes an identifier to lexical search and a
question to hybrid search on its own. It reads a file by outline and span instead of whole.
Results are dense plain text: grouped repo:path and line: snippet rows, folded file
lists, numbered spans. No scores, ranks or JSON punctuation. This costs 54 % fewer tokens
than compact JSON for the same hits. Set INDEXIO_MCP_FORMAT=json for the JSON form.
Token savings, measured
Against the built-in tools, on the same tasks
bench/ab_readme.py runs the tasks a coding agent does through the built-in tools of
Claude Code and through indexio, on the same repositories. Grep prints every match as
path:line:text. Read prints the whole file, 2,000 lines at most. Glob prints one path
per line. Tokens are counted with tiktoken. Three real repositories, 44 in the index, 10
symbols and 3 file types per repository, questions written by a model.
Where the built-in tool is cheaper, the difference is a few hundred tokens. Where it is
expensive, it is expensive by orders of magnitude, because Read returns files and Grep
returns every match of every word.
On real traffic
The server logs every call with the bytes it returned. Where the built-in tool has a
mechanical equivalent, the server also logs what that tool would have returned:
index_stats ends with the last seven days across all sessions. indexio usage prints
the same per tool and per repository. One day of real coding sessions on the author's
machine: 423 compared calls, 220k tokens served where the built-in tools would have
returned 596k, a reduction of 63 %. read_span alone: −71 %.
Impact analysis
The walk is a breadth-first search over the reverse call graph that the index holds. It
costs nothing at index time and answers in milliseconds. A patch is mapped to definitions
with a tree-sitter pass over the changed files only. Changed files are excluded from the
result. Their importers are found with a language-aware import query.
Edges are name-based. Foo::new and Bar::new share the node new. Each site carries its
caller, path and symbol, so an agent can filter. Fan-out caps keep hub names bounded;
truncated: true tells you when a cap fired.
The HTTP API has the same surface: GET /impact/symbol, POST /impact/diff,
GET /outline, GET /span. All of them apply the ACL.
Use indexio from other tools
Any agent framework can use the HTTP API.
A response is a JSON list of hits: repository, path, line, column, snippet, score.
Command reference
Each command accepts --data-dir DIR. The default is $INDEXIO_DATA_DIR, then ~/.indexio.
Index code
Keep it current
Search
Symbols and blast radius
Read from the index
Embeddings
Serve
Agent setup
Run commands without filling the context
A stored log is runs:<repo>/<stamp>-<command>.log: read_span it for the lines the
digest left out, recall finds it later. Logs roll off after INDEXIO_RETAIN_DAYS.
Measure and maintain
Environment variables
Deploy with Docker
The release workflow publishes ghcr.io/ioserviceslabs/indexio for linux/amd64 and
linux/arm64. The image runs as an unprivileged user. The data directory is /data.
git and CA certificates are included.
If you are indexing your own machine for your own agent, install the binary instead.
The container is for a shared index that several people or machines query over HTTP. On
your own laptop it costs you the Bash hooks, the instant working-tree refresh and a layer
of path translation, and buys nothing. Use Install above. The rest of this
section is for the shared case, and for trying indexio without installing anything.
Index a folder on this machine and search it, with nothing installed but Docker:
Serve the HTTP API:
Give the container to an agent as an MCP server (stdio through docker run -i):
How the container indexes code on your machine
The container has no access to your disk beyond what you bind-mount into it. Two mounts
do the work, and they are not symmetric:
indexio add /repos walks the mount, registers every git repository under it at any
depth, and indexes each one. A folder with no git repository in it is indexed as a plain
tree. Each repository is recorded in /data/repos/<name>.json with the path as the
container sees it — /repos/my-service, never C:\Users\you\code\my-service. Results
are repository-relative (my-service:src/main.rs), so searching is unaffected, but the
host path is nowhere in the index.
Three consequences worth knowing before you build a large index:
- A container index and a host index are not interchangeable. If you point the host
binary at a data directory built in a container, the recorded
/repos/... paths do not
exist on the host, so re-indexing and read_span on unindexed content fail. Pick one
and stay with it, or keep two data directories.
- Freshness comes from the sync loop, not from a file watcher.
indexio sync on a
local folder re-discovers the repositories under the root and delta re-indexes whatever
is on disk right now. It does not clone, pull, or write to your source — only the remote
source kinds (github:, azdo:, a git URL) fetch anything. The sync service in
docker-compose.yml runs that every 15 minutes.
- The auto-refresh does not survive the mount.
indexio mcp normally watches the
current repository and re-indexes the working tree in about 25 ms after an edit.
Filesystem events do not cross a Docker Desktop bind mount from a Windows or macOS host
reliably, so in a container treat the index as fresh to the last sync or
refresh_index call, not to the last keystroke. This is the main reason to run the host
binary next to an agent that is editing code.
The Bash hooks (indexio hook install) also need the host binary: they rewrite commands
in your shell, which a container cannot see.
On Windows, generate the serve token in PowerShell rather than with the bash line above:
The image sets INDEXIO_BIND=0.0.0.0, so serve refuses to start without
INDEXIO_AUTH_TOKEN or --acl-file: an index of all your source is not something to
publish unauthenticated. Do not "fix" that by setting INDEXIO_BIND=127.0.0.1 in the
container — the service then binds the container's own loopback and published ports
cannot reach it. Keep the bind at 0.0.0.0, set a token, and publish to
127.0.0.1:7717:7717 so only your machine can connect.
Continuously index one folder
Say the code lives in C:\codebuilds and you want it re-indexed on a timer, with an
agent querying it over MCP. You need no auth token for this: the token guards serve,
the HTTP API, and this setup does not run it.
Register the folder and build the index once. add records /repos as a persistent
source, which is what later syncs re-read:
Then leave a container running that re-syncs on a loop. The image's entrypoint is the
binary, so override it to get a shell:
Point your agent at the same volume. The MCP server is stdio, so it needs no port and no
token:
Check it with docker run --rm -v indexio-data:/data ghcr.io/ioserviceslabs/indexio stats,
which should list every repository found under C:\codebuilds.
Use forward slashes in the mount (C:/codebuilds), and make sure the drive is shared in
Docker Desktop's file-sharing settings. Lower the sleep if 15 minutes is too coarse —
but an edit is visible only after the next sync, so if you want the index to track your
edits as you make them, run the host binary instead.
To use docker-compose.yml for the same thing, set the folder and start only the sync
service:
Compose interpolates the whole file before it selects a service, so
INDEXIO_AUTH_TOKEN must still be set for the file to parse even when you are not
starting the indexio service. Set it as above, or use the plain docker run form.
docker-compose.yml runs two services on one volume:
indexio: the HTTP API, published on localhost only.
sync: indexio sync every 15 minutes. GITHUB_TOKEN and AZDO_TOKEN pass through.
- Put the folders to index under
./repos.
- Start the services:
INDEXIO_AUTH_TOKEN=$(openssl rand -hex 32) docker compose up -d
- Index the folders one time:
docker compose exec sync indexio add /repos
The container binds 0.0.0.0. The binary refuses to start without INDEXIO_AUTH_TOKEN or
an ACL file. docker build -t indexio . builds the same image from source.
Architecture
Five design decisions:
- A trigram index, not a resident AST. indexio parses the AST, takes symbols, call
edges and chunk boundaries from it, and discards it. A resident AST costs 20 to 50 times
the text size. Trigram shards cost 1 to 3 times the corpus and answer in milliseconds.
- A global content-addressed store. Extracted artifacts and embeddings are keyed by
content hash across the organization. A fork, a vendored copy or a duplicated file is
indexed and embedded one time.
- Immutable mmap'd shards with tombstones. An index build writes new shards. A
deletion is a bitmap tombstone.
indexio compact merges shards in the background.
Readers never block writers.
- Git-native delta indexing. A re-index walks the diff of the HEAD tree. Unchanged
blobs are not read, parsed or embedded again. A one-file commit re-indexes in less than
one second.
- An independent semantic plane. The vector index is derived from the store and the
shards. You can change the embedding model or rebuild the plane without touching the
lexical index.
Data layout:
Measured performance
Storage and start-up, measured on the author's machine on a 44-repository, 10,000-file
data directory:
The same lookups through the shell and through the index (bench/ab_speed.py, this
repository, a 1,300-file TypeScript application gives the same picture). Wall-clock,
medians of 10, the index side includes the MCP transport:
Each Bash tool call also pays about 15 ms for the shell and about 30 ms for the two
PreToolUse hooks before its command runs. An MCP call pays neither. On real traffic
(5,355 calls in 7 days) the median is 0 ms for read_span, 12 ms for code_search and
29 ms for code_grep; the 90th percentile stays under 130 ms.
Duplication, measured on a sandbox with 2 cores and 4 GB of RAM:
Lexical latency on the same sandbox: rare identifier 21 ms, common term 81 ms, regex
254 ms. Delta re-index of a one-file commit: 792 ms.
Semantic quality on 20 concept queries (bench/known_answers20.json, bench/eval_modes.py):
Measured and rejected: CombMNZ fusion scored below RRF. An offline overlap reranker scored
below hybrid alone. Thesaurus query expansion scored below plain semantic search. An IVF
prescan gave no speed-up. These stay off by default.
Limits
- No type-resolved cross-references. Call edges are name-based. Overloaded names such
as
new, get and run produce noise. Filter by caller and path.
- Untracked files in
impact --diff. git diff does not include them. Stage them, or
pass a patch.
- The built-in model is not neural. It is useful and cheap. For neural quality, set
INDEXIO_EMBED_BASE.
- MCP has no authentication. It runs as the local user over stdio. Do not expose it to
a network without a gateway.
- No web UI and no distributed query. One binary, one data directory.
Development and releases
Crates: indexio-types (shared types, posting codec), indexio-core (n-grams, verification,
query literals), indexio-index (shards, merge, tombstones), indexio-symbols (tree-sitter
symbols, calls and chunks for 6 languages), indexio-ingest (git delta, content store,
sources), indexio-embed (embedders, embedding store, vector index, pipeline),
indexio-query (planner, ranking, fusion, impact), indexio (CLI, HTTP, MCP, hooks).
docs/DEVELOPMENT.md is the operator manual.
CI (.github/workflows/ci.yml) runs on each push and pull request. It checks that the
manifests parse, the scripts compile and the workflows are valid. It is killed after 90
seconds. The build and the test suite run locally; they do not fit that budget.
Releases (.github/workflows/release.yml) come from main:
- Set
version in Cargo.toml ([workspace.package]).
- Merge to
main. In less than 90 seconds the workflow creates the tag v<version> and a
GitHub release with generated notes. A merge without a version change does nothing.
- The same workflow then builds the binaries for Linux (x86_64, aarch64) and Windows
(x86_64), attaches each archive with a
.sha256 and a pip
wheel to the release, publishes the container image to ghcr.io, publishes the npm
package when the NPM_TOKEN secret exists, and publishes the indexio-cli wheels to
PyPI when the PYPI_API_TOKEN secret exists. These jobs compile Rust and take some
minutes.
tools/release-assets.sh builds and attaches one asset from a maintainer machine, for a
platform the workflow does not cover.
License
Apache License 2.0. See LICENSE and NOTICE.