Elixir Code Review
Quick Reference
| Issue Type | Reference |
|---|---|
| Naming, formatting, module structure | references/code-style.md |
| With clauses, guards, destructuring | references/pattern-matching.md |
| GenServer, Supervisor, Application | references/otp-basics.md |
| @moduledoc, @doc, @spec, doctests | references/documentation.md |
Review Checklist
Code Style
- Module names are CamelCase, function names are snake_case
- Pipe chains start with raw data, not function calls
- Private functions grouped after public functions
- No unnecessary parentheses in function calls without arguments
Pattern Matching
- Functions use pattern matching over conditionals where appropriate
- With clauses have else handling for error cases
- Guards used instead of runtime checks where possible
- Destructuring used in function heads, not body
OTP Basics
- GenServers use handle_continue for expensive init work
- Supervisors use appropriate restart strategies
- No blocking calls in GenServer callbacks
- Proper use of call vs cast (sync vs async)
Documentation
- All public functions have @doc and @spec
- Modules have @moduledoc describing purpose
- Doctests for pure functions where appropriate
- No @doc false on genuinely public functions
Security
- No
String.to_atom/1on user input (useto_existing_atom/1) - No
Code.eval_string/1on untrusted input - No
:erlang.binary_to_term/1without:safeoption
Valid Patterns (Do NOT Flag)
- Empty function clause for pattern match -
def foo(nil), do: nilis valid guard - Using
|>with single transformation - Readability choice, not wrong @doc falseon callback implementations - Callbacks documented at behaviour level- Private functions without @spec - @spec optional for internals
- Using
Kernel.apply/3- Valid for dynamic dispatch with known module/function
Context-Sensitive Rules
| Issue | Flag ONLY IF |
|---|---|
| Missing @spec | Function is public AND exported |
| Generic rescue | Specific exception types available |
| Nested case/cond | More than 2 levels deep |
When to Load References
- Reviewing module/function naming → code-style.md
- Reviewing with/case/cond statements → pattern-matching.md
- Reviewing GenServer/Supervisor code → otp-basics.md
- Reviewing @doc/@moduledoc → documentation.md
Gates — before reporting
Do these in order for the review batch. Do not publish findings until each step passes.
- Protocol loaded — Read review-verification-protocol and apply its checks for each finding category you use (unused, validation, security, performance, etc.). Pass: For every substantive finding, you can name which protocol subsection you satisfied or state N/A with reason (pure style).
- Anchored evidence — Pass: Each finding includes a concrete locator:
path:line(or line range), orModule.function/arityplus a short quoted snippet from the file. - Claims backed by artifacts — For assertions like unused code, missing validation, or security risk, Pass: You attach the supporting artifact (e.g. search results, file read scope) or downgrade the item to an explicit question / uncertain with what you did not verify.
Before Submitting Findings
Complete Gates — before reporting (section above) first; the verification protocol is mandatory input to those gates.