Open source alternative to Resend, Sendgrid, Postmark etc.
This report summarizes scanner evidence for usesend/useSend, a TypeScript project with 4,771 GitHub stars. SynthScan examined 83,419 lines of code across 531 source files, recording 141 pattern matches distributed across 11 syntactic categories. The legacy adjusted pattern signal is 2.4 (Low pattern signal); it is not an authorship estimate.
Use the findings to ask whether maintainers can explain intent, verify dependencies, simplify unnecessary scaffolding, and focus review effort. Risk Payload v1 adds ownership, supply-chain, over-engineering, and review-effort vectors when available. These are prompts for human verification, not probabilities, security findings, or measured maintenance costs.
Use each vector to guide manual verification of the underlying findings.
Payload schema: 1.0.0 · Engine: 2.0.0 · Scoring: heuristic-density-v1 · Scan date: 2026-10-31.
Can maintainers explain intent, assumptions, and trade-offs? 74 finding(s).
Are imports declared and package/API names verified? 46 finding(s).
Are wrappers, guards, and repeated structures necessary? 87 finding(s).
Which changes need focused human review? 141 finding(s).
This chart tracks the legacy adjusted pattern score across scan runs. Changes can reflect source changes, scan coverage, or detector/scoring versions; they do not measure AI adoption or prove that a team refactored code. Compare runs only when their scoring versions are compatible. The dashed line tracks the raw pattern-hit count.
Groups findings by configured severity weight. Severity is not a confidence estimate, security rating, or proof that a package is missing. Verify imports against the project's manifests and inspect each finding in its local design context.
This horizontal bar chart shows where configured pattern scores accumulate across directories. Treat the bars as locations to inspect, not as evidence of authorship or code quality. Use the file-level findings to decide whether a directory needs a focused ownership, dependency, complexity, or review check.
The scanner identified 141 distinct pattern matches across 11 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a detector match to inspect in context. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.
Reading the findings table: The Severity column indicates the configured finding weight (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — legacy comment-context matches receive a ×1.5 score weight. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier under the legacy scoring model.
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | packages/ui/src/charts.tsx | 320 | function getPayloadConfigFromPayload( | CODE |
| LOW | packages/python-sdk/tests/test_resources.py | 40 | def test_contact_books_list_uses_expected_path_and_returns_data() -> None: | CODE |
| LOW | packages/python-sdk/tests/test_resources.py | 75 | def test_contact_books_alias_matches_js_style_client() -> None: | CODE |
| LOW | packages/python-sdk/tests/test_resources.py | 87 | def test_contacts_list_encodes_query_params() -> None: | CODE |
| LOW | packages/python-sdk/tests/test_resources.py | 107 | def test_contacts_bulk_methods_use_expected_payloads() -> None: | CODE |
| LOW | packages/python-sdk/tests/test_webhooks.py | 58 | def test_email_webhook_event_type_excludes_specialized_events() -> None: | CODE |
| LOW | packages/python-sdk/tests/test_webhooks.py | 70 | def test_construct_event_parses_bounced_event_with_valid_signature() -> None: | CODE |
| LOW | packages/email-editor/src/nodes/unsubscribe-footer.tsx | 4 | export function UnsubscribeFooterComponent(props: NodeViewProps) { | CODE |
| LOW | packages/email-editor/src/extensions/SlashCommand.tsx | 398 | export function getSlashCommandSuggestions( | CODE |
| LOW | apps/web/src/app/unsubscribe/page.tsx | 17 | function getUnsubscribeErrorMessage(error: unknown) { | CODE |
| LOW | apps/web/src/app/subscribe/page.tsx | 12 | function getConfirmationErrorMessage(error: unknown) { | CODE |
| LOW | apps/web/src/app/subscribe/page.tsx | 45 | async function confirmSubscriptionAction(formData: FormData) { | CODE |
| LOW | apps/web/src/app/(dashboard)/layout.tsx | 7 | export default function AuthenticatedDashboardLayout({ | CODE |
| LOW | apps/web/src/app/(dashboard)/domains/domain-list.tsx | 47 | function handleClickTrackingChange() { | CODE |
| LOW | …ps/web/src/app/(dashboard)/domains/[domainId]/page.tsx | 185 | function handleClickTrackingChange() { | CODE |
| LOW | …app/(dashboard)/suppressions/bulk-add-suppressions.tsx | 32 | export default function BulkAddSuppressionsDialog({ | CODE |
| LOW | …/[contactBookId]/resend-double-opt-in-confirmation.tsx | 23 | export function ResendDoubleOptInConfirmation({ | CODE |
| LOW | apps/web/src/test/integration/helpers.ts | 30 | export async function closeIntegrationConnections() { | CODE |
| LOW | apps/web/src/server/mailer.ts | 72 | export async function sendSubscriptionConfirmationEmail(email: string) { | CODE |
| LOW | apps/web/src/server/auth.ts | 38 | export async function canRegisterSelfHostedUser( | CODE |
| LOW | …/src/server/email-templates/UsageLimitReachedEmail.tsx | 106 | export async function renderUsageLimitReachedEmail( | CODE |
| LOW | …rver/email-templates/DomainVerificationStatusEmail.tsx | 35 | export function DomainVerificationStatusEmail({ | CODE |
| LOW | …rver/email-templates/DomainVerificationStatusEmail.tsx | 126 | export async function renderDomainVerificationStatusEmail( | CODE |
| LOW | …s/web/src/server/utils/contact-variable-replacement.ts | 13 | export function getContactReplacementValue({ | CODE |
| LOW | …s/web/src/server/utils/contact-variable-replacement.ts | 55 | export function createCaseInsensitiveVariableValues( | CODE |
| LOW | apps/web/src/server/api/routers/admin.ts | 24 | function formatDisplayNameFromEmail(email: string) { | CODE |
| LOW | apps/web/src/server/aws/sns-message-validator.ts | 158 | export async function verifySnsMessageSignature( | CODE |
| LOW | apps/web/src/server/aws/ses.ts | 320 | export async function deleteFromSesSuppressionList( | CODE |
| LOW | apps/web/src/server/jobs/domain-verification-job.ts | 16 | export async function runDueDomainVerifications() { | CODE |
| LOW | apps/web/src/server/jobs/domain-verification-job.ts | 40 | export async function initDomainVerificationJob() { | CODE |
| LOW | apps/web/src/server/service/double-opt-in-service.ts | 37 | function createDoubleOptInConfirmationUrl(contactId: string) { | CODE |
| LOW | apps/web/src/server/service/double-opt-in-service.ts | 49 | export async function sendDoubleOptInConfirmationEmail({ | CODE |
| LOW | apps/web/src/server/service/double-opt-in-service.ts | 167 | export async function confirmDoubleOptInSubscription({ | CODE |
| LOW | apps/web/src/server/service/domain-service.unit.test.ts | 37 | function wasLastNotifiedStatusStored() { | CODE |
| LOW | apps/web/src/server/service/contact-service.ts | 177 | export async function updateContactInContactBook( | CODE |
| LOW | apps/web/src/server/service/contact-service.ts | 230 | export async function deleteContactInContactBook( | CODE |
| LOW | apps/web/src/server/service/contact-service.ts | 255 | export async function bulkDeleteContactsInContactBook( | CODE |
| LOW | apps/web/src/server/service/contact-service.ts | 287 | export async function resendDoubleOptInConfirmationInContactBook( | CODE |
| LOW | apps/web/src/server/service/contact-service.ts | 369 | export async function updateContactSubscription({ | CODE |
| LOW | apps/web/src/server/service/contact-variable-service.ts | 4 | export function normalizeContactBookVariables(variables?: string[]): string[] { | CODE |
| LOW | apps/web/src/server/service/contact-variable-service.ts | 26 | export function validateContactBookVariables(variables: string[]) { | CODE |
| LOW | apps/web/src/server/service/campaign-service.ts | 46 | function campaignHasUnsubscribePlaceholder( | CODE |
| LOW | apps/web/src/server/service/campaign-service.ts | 54 | function replaceUnsubscribePlaceholders(html: string, url: string) { | CODE |
| LOW | apps/web/src/server/service/campaign-service.ts | 102 | async function renderCampaignHtmlForContact({ | CODE |
| LOW | apps/web/src/server/service/campaign-service.ts | 579 | export async function getContactFromUnsubscribeLink(id: string, hash: string) { | CODE |
| LOW | apps/web/src/server/service/campaign-service.ts | 593 | export async function unsubscribeContactFromLink(id: string, hash: string) { | CODE |
| LOW | apps/web/src/server/service/campaign-service.ts | 766 | export async function recordCampaignContactFailure({ | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 127 | async function getDomainVerificationState( | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 149 | async function setDomainVerificationCheckedAt( | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 166 | async function setLastNotifiedDomainStatus( | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 176 | async function reserveDomainStatusNotification( | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 191 | async function clearDomainVerificationState(domainId: number) { | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 215 | function shouldSendDomainStatusNotification({ | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 244 | async function sendDomainStatusNotification({ | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 357 | export async function validateApiKeyDomainAccess( | CODE |
| LOW | apps/web/src/server/service/domain-service.ts | 461 | export async function refreshDomainVerification( | CODE |
| LOW | apps/web/src/server/billing/payments.ts | 29 | export async function createCheckoutSessionForTeam(teamId: number) { | CODE |
| LOW | apps/web/src/lib/subscription-status.ts | 7 | export function isEntitledSubscriptionStatus( | CODE |
| LOW | apps/web/src/lib/contact-properties.ts | 1 | export function getCanonicalContactVariableName( | CODE |
| LOW | apps/web/src/lib/contact-properties.ts | 12 | export function normalizeContactProperties( | CODE |
| 6 more matches not shown… | ||||
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| MEDIUM | packages/python-sdk/usesend/usesend.py | 79 | # ------------------------------------------------------------------ | COMMENT |
| MEDIUM | packages/python-sdk/usesend/usesend.py | 81 | # ------------------------------------------------------------------ | COMMENT |
| MEDIUM | packages/python-sdk/usesend/usesend.py | 107 | # ------------------------------------------------------------------ | COMMENT |
| MEDIUM | packages/python-sdk/usesend/usesend.py | 109 | # ------------------------------------------------------------------ | COMMENT |
| MEDIUM⚡ | packages/python-sdk/usesend/usesend.py | 147 | # ------------------------------------------------------------------ | COMMENT |
| MEDIUM⚡ | packages/python-sdk/usesend/usesend.py | 149 | # ------------------------------------------------------------------ | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 13 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 15 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 103 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 105 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 269 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 271 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 416 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | packages/python-sdk/usesend/types.py | 418 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | packages/python-sdk/usesend/types.py | 520 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | packages/python-sdk/usesend/types.py | 522 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | packages/python-sdk/usesend/types.py | 530 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | packages/python-sdk/usesend/types.py | 532 | # --------------------------------------------------------------------------- | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | …-sdk/example/webhook-test-project/send_test_webhook.py | 1 | CODE | |
| LOW | …es/python-sdk/example/webhook-test-project/receiver.py | 1 | CODE | |
| LOW | packages/python-sdk/usesend/contacts.py | 2 | CODE | |
| LOW | packages/python-sdk/usesend/contacts.py | 119 | CODE | |
| LOW | packages/python-sdk/usesend/usesend.py | 7 | CODE | |
| LOW | packages/python-sdk/usesend/domains.py | 2 | CODE | |
| LOW | packages/python-sdk/usesend/domains.py | 42 | CODE | |
| LOW | packages/python-sdk/usesend/emails.py | 2 | CODE | |
| LOW | packages/python-sdk/usesend/emails.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/emails.py | 107 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 3 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 3 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 4 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 5 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 6 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 7 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 8 | CODE | |
| LOW | packages/python-sdk/usesend/__init__.py | 16 | CODE | |
| LOW | packages/python-sdk/usesend/types.py | 7 | CODE | |
| LOW | packages/python-sdk/usesend/campaigns.py | 2 | CODE | |
| LOW | packages/python-sdk/usesend/campaigns.py | 4 | CODE | |
| LOW | packages/python-sdk/usesend/campaigns.py | 4 | CODE | |
| LOW | packages/python-sdk/usesend/campaigns.py | 68 | CODE | |
| LOW | packages/python-sdk/usesend/webhooks.py | 7 | CODE | |
| LOW | packages/python-sdk/usesend/webhooks.py | 13 | CODE | |
| LOW | packages/python-sdk/usesend/contact_books.py | 2 | CODE | |
| LOW | packages/python-sdk/usesend/contact_books.py | 50 | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | apps/web/prisma/seed_dashboard.sql | 10 | VALUES ('Acme Inc', 'BASIC'::"Plan", TRUE, 10, NOW(), NOW()); | CODE |
| LOW | apps/web/prisma/seed_dashboard.sql | 21 | WHERE "name" = 'Acme Inc' | CODE |
| LOW | apps/web/src/app/api/dev/email-preview/route.ts | 30 | inviterName: "John Doe", | CODE |
| LOW | apps/web/src/app/api/dev/email-preview/route.ts | 38 | teamName: "Acme Inc", | CODE |
| LOW | apps/web/src/app/api/dev/email-preview/route.ts | 49 | teamName: "Acme Inc", | CODE |
| LOW | apps/web/src/app/(dashboard)/admin/waitlist/page.tsx | 127 | placeholder="user@example.com" | CODE |
| LOW | …rc/server/public-api/api/emails/send-email.api.test.ts | 118 | to: "user@example.com", | CODE |
| LOW | apps/web/src/server/api/trpc.trpc.test.ts | 57 | email: "user@example.com", | CODE |
| LOW | …/web/src/server/api/routers/team-security.trpc.test.ts | 42 | email: "admin@example.com", | CODE |
| LOW | apps/web/src/server/service/email-service.unit.test.ts | 170 | to: "user@example.com", | CODE |
| LOW | apps/web/src/server/service/email-service.unit.test.ts | 191 | to: "user@example.com", | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| HIGH | docker/README.md | 53 | -e DATABASE_URL="<your-database-url>" \ | CODE |
| HIGH | apps/web/src/app/(dashboard)/dev-settings/smtp/page.tsx | 60 | value={"YOUR_API_KEY"} | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | references/webhook-architecture.md | 239 | ### Step 1: Event Emission | COMMENT |
| LOW | references/webhook-architecture.md | 255 | ### Step 2: Webhook Matching & Call Creation | COMMENT |
| LOW | references/webhook-architecture.md | 277 | ### Step 3: Queue Processing | COMMENT |
| LOW | references/webhook-architecture.md | 287 | ### Step 4: Payload Structure | COMMENT |
| LOW | references/webhook-architecture.md | 319 | ### Step 5: Request Signing | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| HIGH | apps/marketing/src/components/CodeExample.tsx | 30 | print(data or err)`; | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW⚡ | packages/python-sdk/usesend/usesend.py | 136 | except Exception: | CODE |
| LOW⚡ | packages/python-sdk/usesend/usesend.py | 144 | except Exception: | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | apps/web/next-env.d.ts | 1 | /// <reference types="next" /> | COMMENT |
| LOW | apps/marketing/next-env.d.ts | 1 | /// <reference types="next" /> | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | packages/python-sdk/usesend/__init__.py | 18 | __all__ = [ | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | apps/smtp-server/docker-compose.yml | 9 | SMTP_AUTH_USERNAME: "usesend" # can be anything, just use the same while sending emails | CODE |