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