Add a Go Module Dependency

Important constraints

• The component compiles to a WebAssembly component (WASI) via componentize-go — only code that works on that target will build.
• Modules that use OS threads, raw sockets (net.Dial), most database drivers, cgo, or platform-specific syscalls will not work.
• Pure-Go modules, and modules that do I/O through the standard library the SDK adapts (e.g. HTTP via net/http), generally work.
• If unsure whether a module builds for WASM, add it and run golem build to find out.

Steps

1. Add the dependency in the component’s module directory (where its go.mod lives):

   go get github.com/example/mod@latest

   Then import and use it in your code. go get records it in go.mod.

2. Build to verify

   golem build --yes

   golem build runs go mod tidy for you before compiling. Do NOT rely on a bare go build for the component — it can’t link the WASI component; always use golem build.

3. If the build fails

   • Look for wasip1/wasm-unsupported errors, references to net, syscall, or C dependencies — those modules are incompatible with the WASM target.
   • Check whether the module offers a pure-Go or wasm build mode/build tag.
   • Look for an alternative module that supports WASM.

Already available (do NOT re-add)

• github.com/golemcloud/golem/sdks/go/golem — the Golem Go SDK (agents, durability, RPC, retry, config/secrets, keyvalue/blobstore/rdbms/websocket, logging). Its subpackages (.../golem/retry, .../golem/keyvalue, etc.) are part of the same module.
• github.com/bytecodealliance/componentize-go — pinned as a tool dependency in go.mod so go tool componentize-go runs the pinned version. Leave the tool directive in place; don’t remove it.

HTTP and networking

Use the standard net/http package — the SDK routes it through the durable WASI HTTP transport (see golem-make-http-request-go). Raw sockets (net.Dial, crypto/tls over a custom conn) are not available on the WASM target.

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