gosymdb

A Go symbol and call-graph database backed by SQLite. Index any Go module and query symbols, callers, callees, blast radius, dead code, interface implementors, and type references — all with structured JSON output designed for programmatic consumption.

Project page: https://projects.mioli.dev/gosymdb/ · Blog: https://blog.mioli.dev · Author: Stefano Mioli

What this is

gosymdb is a local, Go-specific symbolic query CLI for coding agents. It uses Go's own package/type analysis (go/packages, go/types — the same loader the compiler uses) to build a persistent SQLite index, then answers repeatable JSON queries such as:

• where is this symbol defined?
• what calls this function?
• what does this function call?
• what breaks if I change this signature?
• what implements this interface?
• where is this type used?
• which symbols are never called?

What this is not

• Not semantic search. Queries are symbolic, not natural-language or embedding-based.
• Not multi-language. Go only.
• Not hosted. Everything runs locally. No telemetry.
• Not a replacement for gopls. It complements gopls — see gosymdb and gopls.
• Not a replacement for Sourcegraph, Augment, or Cursor. Those solve broader multi-language, team-scale, or IDE-native problems.

Install

Homebrew (macOS / Linux)

brew tap walkindude/tap
brew install --cask gosymdb

The cask strips macOS Gatekeeper's quarantine flag post-install so the binary runs on first invocation without xattr gymnastics.

Go toolchain

go install github.com/walkindude/gosymdb@latest

Requires Go 1.26+ on your machine, since this path builds gosymdb from source. The other install methods in this section (Homebrew, scripted installer, Nix, Linux packages) ship pre-compiled binaries and have no Go dependency at install or runtime.

Linux packages (deb / rpm / apk)

Download .deb, .rpm, or .apk for amd64 / arm64 from the latest GitHub release.

Nix

nix profile install github:walkindude/gosymdb
# or one-off:
nix run github:walkindude/gosymdb -- --help
# or drop into a dev shell with go + gopls:
nix develop github:walkindude/gosymdb

Scripted installer (macOS / Linux / Windows)

curl -sSL https://raw.githubusercontent.com/walkindude/gosymdb/master/install.sh | sh

Windows (PowerShell):

iwr -useb https://raw.githubusercontent.com/walkindude/gosymdb/master/install.ps1 | iex

Both installers download the binary, verify its SHA-256 checksum against the release's checksums.txt, and — if Claude Code is installed — generate the cli-bridge spec so gosymdb registers as a first-class MCP tool (see below).

Quick start

# 1. Index a Go module
cd ~/your-go-project
gosymdb index --root .

# 2. Query it
gosymdb find --q Store --json
gosymdb callers --symbol 'github.com/you/repo/pkg.MyFunc' --json
gosymdb blast-radius --symbol 'github.com/you/repo/pkg.MyFunc' --depth 5 --json

Use with Claude Code (MCP)

gosymdb exposes a self-describing manifest (gosymdb cli-bridge-manifest) that the cli-bridge plugin turns into first-class MCP tools. Once set up, agents can call gosymdb_callers, gosymdb_blast-radius, gosymdb_implementors etc. as MCP tools — typed inputs, structured outputs, no grep fallback.

This is the recommended path for agentic use. Agents lose track of CLI tools mentioned only in CLAUDE.md once the conversation gets long; MCP tools live in the agent's tool registry and don't decay under context pressure. (For background on why, see cli-bridge's "The problem" section.)

Three steps:

1. go install github.com/walkindude/gosymdb@latest (or use the installer above; install.sh auto-generates the cli-bridge spec when Claude Code is detected, in which case skip step 3).
2. Install cli-bridge — either as a plugin (/plugin marketplace add walkindude/cli-bridge && /plugin install cli-bridge@cli-bridge) or standalone (npm i -g cli-bridge && claude mcp add cli-bridge -s user -- cli-bridge).
3. Inside Claude Code: /cli-bridge:register gosymdb (uses the canonical cli-bridge-manifest subcommand — no --help scraping).

Restart Claude Code and all gosymdb_* tools appear in the MCP tool list. After upgrading the gosymdb binary, cli-bridge auto-refreshes the spec on its next startup — no manual re-register.

Commands

Command	Description
index	Walk a directory tree, find all go.mod files, build a SQLite symbol + call index
find	Search symbols by name, package, file, or kind
def	Exact single-symbol lookup
callers	Direct or transitive callers of a symbol
callees	What does a function call?
blast-radius	Full transitive impact analysis with test/prod split
dead	Symbols with no callers (dead code candidates)
implementors	Types implementing an interface, or interfaces a type satisfies
references	Where a type is used: assertions, switches, composite literals, conversions
packages	All indexed packages with symbol counts
health	Index quality report
agent-context	One-shot API dump for agent bootstrap
version	Version and schema info

All query commands support --json for structured output.

How it works

gosymdb uses go/packages (the same loader the Go compiler uses) to parse and type-check your code, then walks the AST to extract:

• Symbols: functions, methods, types, interfaces, variables, constants
• Call edges: direct calls, function-value references
• Interface satisfaction: which types implement which interfaces
• Type references: assertions, switches, composite literals, conversions, field access, embedding

Everything is stored in a single SQLite file for fast, offline querying.

Freshness loop

The index goes stale the moment you edit a file. gosymdb closes the loop on its own.

Every JSON response carries an env envelope that always includes env.stale_packages — the list of packages whose source has drifted from what's indexed. The agent sees it on every query, regardless of the command:

$ gosymdb find --q Store --json | jq '.env.stale_packages'
["github.com/you/repo/store"]

Pass --auto-reindex to any query command and stale modules get re-indexed in place before the query runs. The staleness check itself is cheap enough to run on every call: a git fast-path uses git diff against the commit stamped at index time (one subprocess for the whole repo, sub-second on Kubernetes-scale codebases), with a per-file FNV-64a hash fallback for when git isn't usable.

gosymdb callers --symbol 'github.com/you/repo/store.Open' --auto-reindex --json

The shipped CLAUDE.md wires this up for agents: watch env.stale_packages, rebuild or pass --auto-reindex. A silent failure mode (querying a stale index) becomes a self-correcting feedback loop the agent doesn't have to be reminded about.

Known limitations

gosymdb is a static symbolic index, not a runtime tracer. Some things it cannot know:

• Interface dispatch is not recorded as a direct call edge. Use implementors to find concrete types, then run callers/callees against the concrete method. Caller responses include a hint field that flags this when relevant.
• Reflection (reflect.Value.Call, method-value lookups) is not statically resolved.
• go:linkname, plugin loading, and runtime dispatch are not modeled.
• Build tags affect what go/packages loads. Symbols behind tags not active for your host won't be indexed.
• Generated code is indexed only when it exists on disk and is part of the loaded package set — run your generator before indexing.
• CGO is off by default. Pass --cgo to index when indexing CGO-dependent modules.
• Test files are excluded by default. Pass --tests to include *_test.go symbols and the calls they contain.
• Query results depend on index freshness. See Freshness loop — env.stale_packages flags drift on every response, and --auto-reindex self-heals before the query runs.

gosymdb and gopls

gosymdb complements gopls; it is not a replacement.

• gopls is the live Language Server view of a workspace — interactive, in-process, built for the IDE inner loop.
• gosymdb is a persistent SQLite query database — offline, scriptable, built for repeatable agent workflows: callers, callees, blast-radius, implementors, dead-code candidates, references, and --json output that diffs cleanly across runs.

If you're editing code in an IDE, use gopls. If an agent needs to ask structural questions across a long session without maintaining an LSP conversation, use gosymdb.

Privacy

gosymdb runs entirely on your machine. It does not send your source code, symbols, or any data to external servers. There is no telemetry, no phoning home, no network access of any kind. The SQLite database stays on your local disk.

Agent integration

gosymdb is designed for AI coding agents. Every command produces structured JSON with:

• Fully-qualified symbol names (no ambiguity)
• File paths and line numbers (jump-to-definition)
• Structured errors with error_code, hint, and recovery fields
• Environment envelope on every response (env.stale_packages always; env.git branch/dirty state when GOSYMDB_ENV_GIT=1)
• agent-context command for one-shot API discovery

Run gosymdb agent-context at the start of any agent session to get the full command reference.

Environment variables

• GOSYMDB_ENV_GIT=1 — populate the env.git block (branch, dirty count, fetch age, etc.) on every response. Off by default because it costs ~7 subprocess git calls per query; turn it on if your agent consumes this info.

API stability

During v0.x, the supported contract is:

• Command names — index, find, def, callers, callees, blast-radius, dead, implementors, references, packages, health, agent-context, cli-bridge-manifest, version.
• Flag names and types — both command-local flags and the global --db, --json, --auto-reindex.
• JSON output shape — field names, nesting, and error envelopes (error_code, hint, recovery) as emitted when --json is set.
• env block on every JSON response: always env.db and env.stale_packages; env.git when GOSYMDB_ENV_GIT=1.

Breaking changes to any of the above bump the minor version and are called out in release notes. Additive changes (new commands, new fields, new optional flags) are non-breaking and can land in patch releases. Tests consuming gosymdb's JSON should be resilient to unknown fields.

For library users

gosymdb is primarily a CLI. A few Go packages are publicly exported — store, store/sqlite, indexer — to make it possible to plug in alternative store.Store backends or drive the indexer from your own code. They are not intended as a stable library API.

While gosymdb is in v0.x, these packages may change in any minor release: signatures, types, or whole packages can be renamed, moved, or removed. If you import them, pin an exact version and expect to read the changelog on every bump.

License

Apache 2.0 — see LICENSE.