Troubleshooting Golem Build Failures

Both golem and golem-cli can be used — all commands below work with either binary.

For the normal build workflow and golem build usage, load golem-build. This skill focuses on what to do when that build fails.

Build Pipeline Overview

golem build executes a multi-step pipeline. Understanding which step failed is the first step to diagnosing problems:

1. Check — verifies build tools are installed and dependencies are correct
2. Build — runs language-specific compilation commands
3. Add Metadata — embeds component name and version into the output WASM
4. Generate Bridge — generates bridge SDK code for inter-component communication

Run a single step in isolation with --step:

golem build --step check --yes      # Run only the check step
golem build --step build --yes      # Run only the build step

Step 1: Build Tool Requirement Checks

The check step verifies that required system tools are installed and meet minimum version requirements. The checks are language-specific:

Rust Projects

Tool	Check	Install Hint
rustup	rustup --version (minimum version enforced)	https://www.rust-lang.org/tools/install
rustc	rustc --version (minimum version enforced)	rustup install stable && rustup default stable
cargo	cargo version (minimum version enforced)	Installed with Rust toolchain
wasm32-wasip2 target	rustup target list --installed	rustup target add wasm32-wasip2

TypeScript Projects

Tool	Check	Install Hint
node	node --version (minimum version enforced)	https://nodejs.org/
npm	npm --version (minimum version enforced)	Installed with Node.js

MoonBit Projects

Tool	Check	Install Hint
moon	moon version (minimum version enforced)	https://docs.moonbitlang.com

If a tool is missing or below the minimum version, the check step fails with an error message and an install hint. To skip these checks (e.g., if you know tools are installed but detection fails), use --skip-check.

Step 2: Dependency Validation and Auto-Fix

After tool checks, golem build validates project dependencies and can auto-fix them:

Rust Dependency Checks

The CLI inspects every Rust component's Cargo.toml (and workspace Cargo.toml if present) for:

• golem-rust — must be present with a semantically compatible version (or matching path for local development)
• wstd — checked if present, version compatibility verified
• log — checked if present, ensures the kv feature is enabled
• serde — checked if present, ensures the derive feature is enabled
• serde_json — checked if present, version compatibility verified

If dependencies are outdated or missing required features, the CLI shows a diff and prompts for confirmation before applying fixes.

TypeScript Dependency Checks

The CLI inspects the root package.json for:

• @golemcloud/golem-ts-sdk — must be present with a compatible version
• Rollup plugins (@rollup/plugin-node-resolve, @rollup/plugin-typescript, @rollup/plugin-commonjs, @rollup/plugin-json) — version compatibility checked
• typescript, rollup, tslib, @types/node — version compatibility checked

The CLI also validates tsconfig.json settings:

• compilerOptions.moduleResolution must be "bundler"

AGENTS.md and Skill Files

The CLI checks that the project's AGENTS.md and .agents/skills/ directory contain up-to-date content matching the current CLI version's templates. If they are stale, the CLI updates them automatically during the build.

Viewing Planned Fixes Without Applying

Run the check step alone to see what the CLI wants to fix without building:

golem build --step check --yes

Common Build Errors and Solutions

"X is not available" / Tool Not Found

The CLI cannot find a required tool. Check that it is installed and on your PATH:

which cargo     # Rust
which node      # TypeScript
which moon      # MoonBit

"X version could not be detected"

The CLI found the tool but could not parse its version. This usually means a non-standard version string. Try updating the tool.

Missing Rust Target

rust target wasm32-wasip2 is not installed

Fix: rustup target add wasm32-wasip2

Dependency Version Mismatch

The CLI shows a diff of the changes it wants to make. Review the diff — it will update version numbers or add missing features. Pass --yes to auto-accept.

TypeScript tsconfig.json Issues

If moduleResolution is not set to "bundler", the build will fail during type checking. The CLI auto-fixes this during the check step.

Up-to-Date Check Confusion

golem build tracks file hashes to skip unchanged steps. If files were modified outside the build (e.g., by cargo build), the check may be stale. Force a full rebuild:

golem build --force-build --yes

Or clean and rebuild:

golem clean
golem build --yes

Diagnosing Manifest Configuration Issues with manifest-trace

When environment variables, config, plugins, or files are not what you expect at runtime, use manifest-trace to see exactly how the manifest configuration is resolved:

golem component manifest-trace

This command outputs a detailed trace for each component showing:

• Applied Layers — the ordered list of configuration layers that contributed to the final values (e.g., component template, component definition, agent template, agent common, environment presets, custom presets)
• Property Values and Origins — for each property (config, env, wasiConfig, plugins, files, build, clean, componentWasm, outputWasm), the final resolved value plus a trace of which layer introduced or modified it
• Merge Operations — whether values were merged (showing inserted/updated entries) or entirely replaced, and from which layer

Example Usage

# Trace all components
golem component manifest-trace

# Trace a specific component
golem component manifest-trace my-app:main

What to Look For

1. Missing environment variables: Check the env property trace to see if the variable was defined in a layer that was overridden or replaced by a later layer
2. Wrong config values: Check the config property trace — a later layer may have replaced the entire config object instead of merging individual fields
3. Plugin not applied: Check the plugins property trace to see if the plugin was defined in a layer that is not in the appliedLayers list (e.g., an environment that is not active)
4. Unexpected merge behavior: Check envMergeMode, pluginsMergeMode, or filesMergeMode — these control whether later layers merge with or replace earlier values
5. Preset not active: Verify that the expected preset appears in appliedLayers — if it is missing, it may not be set as the default or selected via the environment

Combining with Environment Selection

To see how the trace changes under a specific environment:

golem component manifest-trace -e staging

This activates the staging environment's presets, letting you verify that environment-specific overrides are applied correctly.

Related Skills

• Load golem-build for the normal golem build workflow and options