eroslifestyle Build Fix Skill - Automated Build Error Resolution
Purpose
Detect the project's build system, run the build, parse errors, and automatically fix them in an iterative loop until the build succeeds.
Trigger
User invokes /build-fix [command] or orchestrator delegates build-fix tasks.
[command]: optional override for build command (e.g.,npm run build)- If omitted, auto-detects build system
Algorithm
Step 1: DETECT Build System
Detect in priority order via Glob/Read:
| File | Build Command |
|---|---|
package.json (scripts.build) |
npm run build or yarn build |
Makefile |
make |
pyproject.toml (build-system) |
python -m build or pip install -e . |
Cargo.toml |
cargo build |
go.mod |
go build ./... |
CMakeLists.txt |
cmake --build build/ |
build.gradle |
./gradlew build |
pom.xml |
mvn compile |
If none found, ask user for build command.
Step 2: RUN Build (Iteration Loop)
iteration = 0
MAX_ITERATIONS = 3
while iteration < MAX_ITERATIONS:
iteration += 1
1. RUN build command via Bash (capture stdout + stderr)
2. IF build succeeds -> REPORT SUCCESS, exit loop
3. PARSE errors from output (see Error Parsing below)
4. For each error (all independent fixes in parallel):
a. READ the file at error location
b. DETERMINE fix type
c. APPLY fix via Edit
5. Continue loop (re-run build)
IF iteration == MAX_ITERATIONS and still failing:
REPORT remaining errors to user
Step 3: REPORT Results
Error Parsing Patterns
TypeScript/JavaScript
Pattern: ^(.+)\((\d+),(\d+)\): error (TS\d+): (.+)$
^(.+):(\d+):(\d+): error: (.+)$
Extract: file, line, column, error_code, message
Python
Pattern: ^ File "(.+)", line (\d+)
^(\w+Error): (.+)$
^SyntaxError: (.+) \((.+), line (\d+)\)
Extract: file, line, error_type, message
Rust
Pattern: ^error\[E(\d+)\]: (.+)
^\s+--> (.+):(\d+):(\d+)
Extract: error_code, message, file, line, column
Go
Pattern: ^(.+):(\d+):(\d+): (.+)$
Extract: file, line, column, message
Generic (fallback)
Pattern: ^(.+):(\d+).*(?:error|Error|ERROR).*: (.+)$
Extract: file, line, message
Common Fix Strategies
| Error Type | Fix Strategy |
|---|---|
| Missing import | Add the import statement |
| Type mismatch | Adjust type annotation or cast |
| Undefined variable | Check for typo, add declaration |
| Missing module | Check package.json/requirements.txt, suggest install |
| Syntax error | Read context, fix syntax |
| Missing return | Add return statement |
| Unused variable | Remove or prefix with underscore |
| Missing dependency | Run install command |
| Missing file | Check if renamed/moved, update import path |
Output Format
# Build Fix Report
## Build System
- Detected: <system name>
- Command: `<build command>`
## Iterations
### Iteration 1
- Errors found: <N>
- Errors fixed: <M>
| File | Line | Error | Fix Applied |
|------|------|-------|-------------|
| src/main.ts | 42 | TS2304: Cannot find name 'Foo' | Added import { Foo } from './types' |
### Iteration 2
- Errors found: <N>
- Errors fixed: <M>
...
## Final Status
- Result: SUCCESS / PARTIAL / FAILED
- Build clean: YES / NO
- Remaining errors: <N> (if any, list them)
Rules
- Maximum 3 build-fix iterations to prevent infinite loops
- ALWAYS capture both stdout and stderr from build command
- Fix errors in order: syntax errors first, then type errors, then logic errors
- If a fix introduces new errors, revert that specific fix
- NEVER modify test files to fix build errors (unless the test itself has a syntax error)
- If build requires install step first (e.g., npm install), run it before building
- Report the exact build command used so user can reproduce
- Timeout: 120 seconds per build attempt (kill if exceeds)