diff --git a/site/source/components/FicheDePaie/CotisationLine.tsx b/site/source/components/FicheDePaie/CotisationLine.tsx
index 3cbf9d61b..3085da959 100644
--- a/site/source/components/FicheDePaie/CotisationLine.tsx
+++ b/site/source/components/FicheDePaie/CotisationLine.tsx
@@ -1,10 +1,9 @@
 import { DottedName } from 'modele-social'
 import { formatValue } from 'publicodes'
-import { useContext } from 'react'
 import { useTranslation } from 'react-i18next'
 
 import RuleLink from '@/components/RuleLink'
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { findReferenceInNode } from '@/utils/publicodes'
 
 export default function CotisationLine({
@@ -13,7 +12,7 @@ export default function CotisationLine({
 	dottedName: DottedName
 }) {
 	const language = useTranslation().i18n.language
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	const partSalariale = engine.evaluate(
 		findReferenceInNode(
 			dottedName,
diff --git a/site/source/components/References.tsx b/site/source/components/References.tsx
index 28d4cf1e7..0b024bc6d 100644
--- a/site/source/components/References.tsx
+++ b/site/source/components/References.tsx
@@ -1,9 +1,8 @@
 import { DottedName } from 'modele-social'
 import { utils } from 'publicodes'
-import { useContext } from 'react'
 import { styled } from 'styled-components'
 
-import { EngineContext, useEngine } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { Grid } from '@/design-system/layout'
 import { Link } from '@/design-system/typography/link'
 import { Li, Ul } from '@/design-system/typography/list'
@@ -131,7 +130,7 @@ const getDomain = (link: string) =>
 	)
 
 export function RuleReferences({ dottedNames }: { dottedNames: DottedName[] }) {
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 
 	return (
 		<Ul>
diff --git a/site/source/components/RuleLink.tsx b/site/source/components/RuleLink.tsx
index cb6b935f9..481353837 100644
--- a/site/source/components/RuleLink.tsx
+++ b/site/source/components/RuleLink.tsx
@@ -1,12 +1,12 @@
 import { RuleLink as EngineRuleLink } from '@publicodes/react-ui'
 import { DottedName } from 'modele-social'
 import Engine from 'publicodes'
-import React, { ReactNode, useContext } from 'react'
+import React, { ReactNode } from 'react'
 
 import { Link } from '@/design-system/typography/link'
 import { useSitePaths } from '@/sitePaths'
 
-import { EngineContext } from './utils/EngineContext'
+import { useEngine } from './utils/EngineContext'
 
 // TODO : quicklink -> en cas de variations ou de somme avec un seul élément actif, faire un lien vers cet élément
 export default function RuleLink(
@@ -20,7 +20,7 @@ export default function RuleLink(
 	} & Omit<React.ComponentProps<typeof Link>, 'to' | 'children'>
 ) {
 	const { absoluteSitePaths } = useSitePaths()
-	const defaultEngine = useContext(EngineContext)
+	const defaultEngine = useEngine()
 
 	const engineUsed = props?.engine ?? defaultEngine
 
diff --git a/site/source/components/conversation/Explicable.tsx b/site/source/components/conversation/Explicable.tsx
index 1337959e0..9186134ae 100644
--- a/site/source/components/conversation/Explicable.tsx
+++ b/site/source/components/conversation/Explicable.tsx
@@ -1,7 +1,6 @@
 import { DottedName } from 'modele-social'
-import { useContext } from 'react'
 
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { Markdown } from '@/components/utils/markdown'
 import HelpButtonWithPopover from '@/design-system/buttons/HelpButtonWithPopover'
 import { Spacing } from '@/design-system/layout'
@@ -23,8 +22,8 @@ export function ExplicableRule<Names extends string = DottedName>({
 	bigPopover?: boolean
 	title?: string
 }) {
-	const engine = useContext(EngineContext)
-	const rule = engine.getRule(dottedName)
+	const engine = useEngine()
+	const rule = engine.getRule(dottedName as DottedName)
 	const références = useReferences(rule)
 
 	if (rule.rawNode.description == null) {
diff --git a/site/source/components/conversation/NumberInput.tsx b/site/source/components/conversation/NumberInput.tsx
index 9db44806b..829fc9bef 100644
--- a/site/source/components/conversation/NumberInput.tsx
+++ b/site/source/components/conversation/NumberInput.tsx
@@ -1,10 +1,10 @@
 import { NumberFieldProps } from '@react-types/numberfield'
 import { ASTNode, parseUnit, serializeUnit, Unit } from 'publicodes'
-import { useCallback, useContext, useEffect, useState } from 'react'
+import { useCallback, useEffect, useState } from 'react'
 import { useTranslation } from 'react-i18next'
 import { styled } from 'styled-components'
 
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { NumberField } from '@/design-system/field'
 import { debounce } from '@/utils'
 
@@ -33,7 +33,7 @@ export default function NumberInput({
 	)
 	const { i18n } = useTranslation()
 	const parsedDisplayedUnit = displayedUnit ? parseUnit(displayedUnit) : unit
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	useEffect(() => {
 		if (value !== currentValue) {
 			setCurrentValue(
diff --git a/site/source/components/conversation/RuleInput.tsx b/site/source/components/conversation/RuleInput.tsx
index 666d9f813..1574fe1c7 100644
--- a/site/source/components/conversation/RuleInput.tsx
+++ b/site/source/components/conversation/RuleInput.tsx
@@ -7,11 +7,11 @@ import Engine, {
 	reduceAST,
 	RuleNode,
 } from 'publicodes'
-import React, { useContext } from 'react'
+import React from 'react'
 
 import NumberInput from '@/components/conversation/NumberInput'
 import SelectCommune from '@/components/conversation/select/SelectCommune'
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { DateFieldProps } from '@/design-system/field/DateField'
 import { Spacing } from '@/design-system/layout'
 import { getMeta } from '@/utils/publicodes'
@@ -84,7 +84,7 @@ export default function RuleInput<Names extends string = DottedName>({
 	engine,
 	...props
 }: Props<Names>) {
-	const defaultEngine = useContext(EngineContext)
+	const defaultEngine = useEngine() as Engine<string>
 
 	const engineValue = (engine ?? defaultEngine) as Engine<Names>
 
diff --git a/site/source/components/layout/Footer/PrivacyPolicy.tsx b/site/source/components/layout/Footer/PrivacyPolicy.tsx
index 8c5f63720..7f6d3502f 100644
--- a/site/source/components/layout/Footer/PrivacyPolicy.tsx
+++ b/site/source/components/layout/Footer/PrivacyPolicy.tsx
@@ -1,4 +1,4 @@
-import { useCallback, useContext, useState } from 'react'
+import { useCallback, useState } from 'react'
 import { Trans, useTranslation } from 'react-i18next'
 import { styled } from 'styled-components'
 
diff --git a/site/source/pages/assistants/components/Fields.tsx b/site/source/pages/assistants/components/Fields.tsx
index a00af0864..ff434f3e3 100644
--- a/site/source/pages/assistants/components/Fields.tsx
+++ b/site/source/pages/assistants/components/Fields.tsx
@@ -1,14 +1,14 @@
 import { useSSRSafeId } from '@react-aria/ssr'
 import { DottedName } from 'modele-social'
 import { PublicodesExpression, RuleNode } from 'publicodes'
-import { useCallback, useContext } from 'react'
+import { useCallback } from 'react'
 import { useDispatch, useSelector } from 'react-redux'
 import { IStyledComponent, styled } from 'styled-components'
 
 import { ExplicableRule } from '@/components/conversation/Explicable'
 import RuleInput from '@/components/conversation/RuleInput'
 import { FadeIn } from '@/components/ui/animate'
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { Markdown } from '@/components/utils/markdown'
 import { Spacing } from '@/design-system/layout'
 import { H3 } from '@/design-system/typography/heading'
@@ -32,7 +32,7 @@ export function SubSection({
 	hideTitle = false,
 	without = [],
 }: SubSectionProp) {
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	const ruleTitle = engine.getRule(sectionDottedName)?.title
 	const nextSteps = useNextQuestions()
 	const situation = useSelector(situationSelector)
@@ -86,7 +86,7 @@ export function SimpleField(props: SimpleFieldProps) {
 		labelStyle,
 	} = props
 	const dispatch = useDispatch()
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	const evaluation = engine.evaluate(dottedName)
 	const rule = engine.getRule(dottedName)
 	const meta = getMeta<{ requis?: 'oui' | 'non' }>(rule.rawNode, {})
diff --git a/site/source/pages/assistants/demande-mobilité/EndBlock.tsx b/site/source/pages/assistants/demande-mobilité/EndBlock.tsx
index 133879c55..b363ea2cc 100644
--- a/site/source/pages/assistants/demande-mobilité/EndBlock.tsx
+++ b/site/source/pages/assistants/demande-mobilité/EndBlock.tsx
@@ -1,12 +1,12 @@
 import { BlobProvider } from '@react-pdf/renderer'
 import { RuleNode, utils } from 'publicodes'
-import { lazy, Suspense, useContext, useRef, useState } from 'react'
+import { lazy, Suspense, useRef, useState } from 'react'
 import SignaturePad from 'react-signature-pad-wrapper'
 import { useTheme } from 'styled-components'
 
 import { TrackPage, useTracking } from '@/components/ATInternetTracking'
 import { Condition } from '@/components/EngineValue/Condition'
-import { EngineContext, EngineProvider } from '@/components/utils/EngineContext'
+import { EngineProvider, useEngine } from '@/components/utils/EngineContext'
 import { Message, PopoverWithTrigger } from '@/design-system'
 import { Button } from '@/design-system/buttons'
 import { Emoji } from '@/design-system/emoji'
@@ -30,7 +30,7 @@ type EndBlockProps = {
 export default function EndBlock({ fields, missingValues }: EndBlockProps) {
 	const [isCertified, setCertified] = useState(false)
 	const [place, setPlace] = useState<string>()
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	const signatureRef = useRef<SignaturePad | null>(null)
 	const tracker = useTracking()
 	const { colors } = useTheme()
diff --git a/site/source/pages/assistants/demande-mobilité/FieldsPDF.tsx b/site/source/pages/assistants/demande-mobilité/FieldsPDF.tsx
index f2f7fac73..349573c29 100644
--- a/site/source/pages/assistants/demande-mobilité/FieldsPDF.tsx
+++ b/site/source/pages/assistants/demande-mobilité/FieldsPDF.tsx
@@ -1,8 +1,7 @@
 import PDFElement from '@react-pdf/renderer'
 import { formatValue, RuleNode } from 'publicodes'
-import { useContext } from 'react'
 
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 
 const { StyleSheet, Text, View } = PDFElement
 type FieldsPDFProps = {
@@ -10,7 +9,7 @@ type FieldsPDFProps = {
 }
 
 export default function FieldsPDF({ fields }: FieldsPDFProps) {
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 
 	return (
 		<>
diff --git a/site/source/pages/assistants/demande-mobilité/index.tsx b/site/source/pages/assistants/demande-mobilité/index.tsx
index 405080aea..d350d19f5 100644
--- a/site/source/pages/assistants/demande-mobilité/index.tsx
+++ b/site/source/pages/assistants/demande-mobilité/index.tsx
@@ -1,6 +1,7 @@
 import { DottedName } from 'modele-social'
-import Engine, { PublicodesExpression } from 'publicodes'
-import { Fragment, lazy, Suspense, useCallback, useContext } from 'react'
+import { Names } from 'modele-social/dist/names'
+import Engine, { PublicodesExpression, Rule } from 'publicodes'
+import { Fragment, lazy, Suspense, useCallback } from 'react'
 import { Trans, useTranslation } from 'react-i18next'
 
 import { TrackPage } from '@/components/ATInternetTracking'
@@ -9,7 +10,7 @@ import { WhenApplicable } from '@/components/EngineValue/WhenApplicable'
 import { WhenNotApplicable } from '@/components/EngineValue/WhenNotApplicable'
 import { Appear } from '@/components/ui/animate'
 import BrowserOnly from '@/components/utils/BrowserOnly'
-import { EngineContext, EngineProvider } from '@/components/utils/EngineContext'
+import { EngineProvider, useEngine } from '@/components/utils/EngineContext'
 import { Markdown } from '@/components/utils/markdown'
 import { usePersistingState } from '@/components/utils/persistState'
 import { Button } from '@/design-system/buttons'
@@ -32,7 +33,7 @@ const LazyEndBlock = import.meta.env.SSR
 	: lazy(() => import('./EndBlock'))
 
 export default function PageMobilité() {
-	const engine = new Engine(formulaire)
+	const engine = new Engine(formulaire as Record<Names, Rule>)
 
 	return (
 		<>
@@ -70,7 +71,7 @@ const useFields = (
 
 const VERSION = hash(JSON.stringify(formulaire))
 function FormulairePublicodes() {
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	const [situation, setSituation] = usePersistingState<
 		Record<string, PublicodesExpression>
 	>(`formulaire-détachement:${VERSION}`, {})
@@ -81,7 +82,9 @@ function FormulairePublicodes() {
 		(dottedName: string, value?: PublicodesExpression) => {
 			if (value === undefined) {
 				setSituation((situation) => omit(situation, dottedName))
-			} else if (engine.getRule(dottedName).rawNode.API === 'commune') {
+			} else if (
+				engine.getRule(dottedName as DottedName).rawNode.API === 'commune'
+			) {
 				type Value = {
 					batchUpdate: {
 						nom: PublicodesExpression
@@ -123,7 +126,7 @@ function FormulairePublicodes() {
 			}),
 			{}
 		)
-	).map((dottedName) => engine.getRule(dottedName))
+	).map((dottedName) => engine.getRule(dottedName as DottedName))
 
 	return (
 		<>
@@ -180,7 +183,7 @@ function FormulairePublicodes() {
 												<Markdown>
 													{evaluateQuestion(
 														engine,
-														engine.getRule(dottedName)
+														engine.getRule(dottedName as DottedName)
 													) ?? ''}
 												</Markdown>
 											</div>
@@ -193,7 +196,10 @@ function FormulairePublicodes() {
 											hideDefaultValue
 											aria-label={
 												question &&
-												evaluateQuestion(engine, engine.getRule(dottedName))
+												evaluateQuestion(
+													engine,
+													engine.getRule(dottedName as DottedName)
+												)
 											}
 										/>
 										{question && type === undefined && description && (
diff --git a/site/source/pages/simulateurs/artiste-auteur/ArtisteAuteur.tsx b/site/source/pages/simulateurs/artiste-auteur/ArtisteAuteur.tsx
index 871ec24bd..b10b52129 100644
--- a/site/source/pages/simulateurs/artiste-auteur/ArtisteAuteur.tsx
+++ b/site/source/pages/simulateurs/artiste-auteur/ArtisteAuteur.tsx
@@ -1,4 +1,3 @@
-import { useContext } from 'react'
 import { Trans } from 'react-i18next'
 import { useLocation } from 'react-router-dom'
 
@@ -12,7 +11,7 @@ import Simulation, {
 } from '@/components/Simulation'
 import { DistributionBranch } from '@/components/simulationExplanation/DistributionDesCotisations'
 import { InstitutionsPartenairesArtisteAuteur } from '@/components/simulationExplanation/InstitutionsPartenaires'
-import { EngineContext } from '@/components/utils/EngineContext'
+import { useEngine } from '@/components/utils/EngineContext'
 import { H2 } from '@/design-system/typography/heading'
 import { Body } from '@/design-system/typography/paragraphs'
 import useSimulationConfig from '@/hooks/useSimulationConfig'
@@ -85,7 +84,7 @@ const branches = [
 ] as const
 
 function RepartitionCotisations() {
-	const engine = useContext(EngineContext)
+	const engine = useEngine()
 	const cotisations = branches.map((branch) => ({
 		...branch,
 		value: engine.evaluate(branch.dottedName).nodeValue as number,