williamlimasilva/salesforce-flow-design

Salesforce Flow Design and Validation

Apply these checks to every Flow you design, build, or review.

Step 1 — Confirm Flow Is the Right Tool

Before designing a Flow, verify that a lighter-weight declarative option cannot solve the problem:

| Requirement | Best tool | |---|---| | Calculate a field value with no side effects | Formula field | | Prevent a bad record save with a user message | Validation rule | | Sum or count child records on a parent | Roll-up Summary field | | Complex multi-object logic, callouts, or high volume | Apex (Queueable / Batch) — not Flow | | Everything else | Flow ✓ |

If you are building a Flow that could be replaced by a formula field or validation rule, ask the user to confirm the requirement is genuinely more complex.

Step 2 — Select the Correct Flow Type

| Use case | Flow type | Key constraint | |---|---|---| | Update a field on the same record before it is saved | Before-save Record-Triggered | Cannot send emails, make callouts, or change related records | | Create/update related records, emails, callouts | After-save Record-Triggered | Runs after commit — avoid recursion traps | | Guide a user through a multi-step UI process | Screen Flow | Cannot be triggered by a record event automatically | | Reusable background logic called from another Flow | Autolaunched (Subflow) | Input/output variables define the contract | | Logic invoked from Apex @InvocableMethod | Autolaunched (Invocable) | Must declare input/output variables | | Time-based batch processing | Scheduled Flow | Runs in batch context — respect governor limits | | Respond to events (Platform Events / CDC) | Platform Event–Triggered | Runs asynchronously — eventual consistency |

Decision rule: choose before-save when you only need to change the triggering record's own fields. Move to after-save the moment you need to touch related records, send emails, or make callouts.

Step 3 — Bulk Safety Checklist

These patterns are governor limit failures at scale. Check for all of them before the Flow is activated.

DML in Loops — Automatic Fail

Loop element
  └── Create Records / Update Records / Delete Records  ← ❌ DML inside loop

Fix: collect records inside the loop into a collection variable, then run the DML element outside the loop.

Get Records in Loops — Automatic Fail

Loop element
  └── Get Records  ← ❌ SOQL inside loop

Fix: perform the Get Records query before the loop, then loop over the collection variable.

Correct Bulk Pattern

Get Records — collect all records in one query
└── Loop over the collection variable
    └── Decision / Assignment (no DML, no Get Records)
└── After the loop: Create/Update/Delete Records — one DML operation

Transform vs Loop

When the goal is reshaping a collection (e.g. mapping field values from one object to another), use the Transform element instead of a Loop + Assignment pattern. Transform is bulk-safe by design and produces cleaner Flow graphs.

Step 4 — Fault Path Requirements

Every element that can fail at runtime must have a fault connector. Flows without fault paths surface raw system errors to users.

Elements That Require Fault Connectors

• Create Records
• Update Records
• Delete Records
• Get Records (when accessing a required record that might not exist)
• Send Email
• HTTP Callout / External Service action
• Apex action (invocable)
• Subflow (if the subflow can throw a fault)

Fault Handler Pattern

Fault connector → Log Error (Create Records on a logging object or fire a Platform Event)
               → Screen element with user-friendly message (Screen Flows)
               → Stop / End element (Record-Triggered Flows)

Never connect a fault path back to the same element that faulted — this creates an infinite loop.

Step 5 — Automation Density Check

Before deploying, verify there are no overlapping automations on the same object and trigger event:

• Other active Record-Triggered Flows on the same Object + When to Run combination
• Legacy Process Builder rules still active on the same object
• Workflow Rules that fire on the same field changes
• Apex triggers that also run on the same before insert / after update context

Overlapping automations can cause unexpected ordering, recursion, and governor limit failures. Document the automation inventory for the object before activating.

Step 6 — Screen Flow UX Guidelines

• Every path through a Screen Flow must reach an End element — no orphan branches.
• Provide a Back navigation option on multi-step flows unless back-navigation would corrupt data.
• Use lightning-input and SLDS-compliant components for all user inputs — do not use HTML form elements.
• Validate required inputs on the screen before the user can advance — use Flow validation rules on the screen.
• Handle the Pause element if the flow may need to await user action across sessions.

Step 7 — Deployment Safety

Deploy as Draft    →   Test with 1 record   →   Test with 200+ records   →   Activate

• Always deploy as Draft first and test thoroughly before activation.
• For Record-Triggered Flows: test with the exact entry conditions (e.g. ISCHANGED(Status) — ensure the test data actually triggers the condition).
• For Scheduled Flows: test with a small batch in a sandbox before enabling in production.
• Check the Automation Density score for the object — more than 3 active automations on a single object increases order-of-execution risk.

Quick Reference — Flow Anti-Patterns Summary

| Anti-pattern | Risk | Fix | |---|---|---| | DML element inside a Loop | Governor limit exception | Move DML outside the loop | | Get Records inside a Loop | SOQL governor limit exception | Query before the loop | | No fault connector on DML/email/callout element | Unhandled exception surfaced to user | Add fault path to every such element | | Updating the triggering record in an after-save flow with no recursion guard | Infinite trigger loops | Add an entry condition or recursion guard variable | | Looping directly on $Record collection | Incorrect behaviour at scale | Assign to a collection variable first, then loop | | Process Builder still active alongside a new Flow | Double-execution, unexpected ordering | Deactivate Process Builder before activating the Flow | | Screen Flow with no End element on all branches | Runtime error or stuck user | Ensure every branch resolves to an End element |