diff --git a/test/context/context.go b/test/context/context.go
index 59f76737..b1538590 100644
--- a/test/context/context.go
+++ b/test/context/context.go
@@ -19,6 +19,8 @@
 package context
 
 import (
+	"sync"
+
 	"github.com/ProtonMail/proton-bridge/internal/bridge"
 	"github.com/ProtonMail/proton-bridge/internal/importexport"
 	"github.com/ProtonMail/proton-bridge/internal/transfer"
@@ -56,16 +58,18 @@ type TestContext struct {
 	lastError    error
 
 	// IMAP related variables.
-	imapAddr          string
-	imapServer        server
-	imapClients       map[string]*mocks.IMAPClient
-	imapLastResponses map[string]*mocks.IMAPResponse
+	imapAddr           string
+	imapServer         server
+	imapClients        map[string]*mocks.IMAPClient
+	imapLastResponses  map[string]*mocks.IMAPResponse
+	imapResponseLocker sync.Locker
 
 	// SMTP related variables.
-	smtpAddr          string
-	smtpServer        server
-	smtpClients       map[string]*mocks.SMTPClient
-	smtpLastResponses map[string]*mocks.SMTPResponse
+	smtpAddr           string
+	smtpServer         server
+	smtpClients        map[string]*mocks.SMTPClient
+	smtpLastResponses  map[string]*mocks.SMTPResponse
+	smtpResponseLocker sync.Locker
 
 	// Transfer related variables.
 	transferLocalRootForImport    string
@@ -102,8 +106,10 @@ func New(app string) *TestContext {
 		credStore:             newFakeCredStore(),
 		imapClients:           make(map[string]*mocks.IMAPClient),
 		imapLastResponses:     make(map[string]*mocks.IMAPResponse),
+		imapResponseLocker:    &sync.Mutex{},
 		smtpClients:           make(map[string]*mocks.SMTPClient),
 		smtpLastResponses:     make(map[string]*mocks.SMTPResponse),
+		smtpResponseLocker:    &sync.Mutex{},
 		bddMessageIDsToAPIIDs: make(map[string]string),
 		logger:                logrus.StandardLogger(),
 	}
diff --git a/test/context/imap.go b/test/context/imap.go
index 6218eee4..0cccf10e 100644
--- a/test/context/imap.go
+++ b/test/context/imap.go
@@ -71,10 +71,16 @@ func (ctx *TestContext) withIMAPServer() {
 
 // SetIMAPLastResponse sets the last IMAP response that was received.
 func (ctx *TestContext) SetIMAPLastResponse(handle string, resp *mocks.IMAPResponse) {
+	ctx.imapResponseLocker.Lock()
+	defer ctx.imapResponseLocker.Unlock()
+
 	ctx.imapLastResponses[handle] = resp
 }
 
 // GetIMAPLastResponse returns the last IMAP response that was received.
 func (ctx *TestContext) GetIMAPLastResponse(handle string) *mocks.IMAPResponse {
+	ctx.imapResponseLocker.Lock()
+	defer ctx.imapResponseLocker.Unlock()
+
 	return ctx.imapLastResponses[handle]
 }
diff --git a/test/context/smtp.go b/test/context/smtp.go
index 52090788..cbcada94 100644
--- a/test/context/smtp.go
+++ b/test/context/smtp.go
@@ -72,10 +72,16 @@ func (ctx *TestContext) withSMTPServer() {
 
 // SetSMTPLastResponse sets the last SMTP response that was received.
 func (ctx *TestContext) SetSMTPLastResponse(handle string, resp *mocks.SMTPResponse) {
+	ctx.smtpResponseLocker.Lock()
+	defer ctx.smtpResponseLocker.Unlock()
+
 	ctx.smtpLastResponses[handle] = resp
 }
 
 // GetSMTPLastResponse returns the last IMAP response that was received.
 func (ctx *TestContext) GetSMTPLastResponse(handle string) *mocks.SMTPResponse {
+	ctx.smtpResponseLocker.Lock()
+	defer ctx.smtpResponseLocker.Unlock()
+
 	return ctx.smtpLastResponses[handle]
 }
diff --git a/unreleased.md b/unreleased.md
index 9f3b0c29..b74de3a8 100644
--- a/unreleased.md
+++ b/unreleased.md
@@ -13,6 +13,7 @@ Changelog [format](http://keepachangelog.com/en/1.0.0/)
 * GODT-338 GODT-781 GODT-857 GODT-866 Flaky tests.
 * GODT-773 Replace old dates with birthday of RFC822 to not crash Apple Mail. Original is available under `X-Original-Date` header.
 * GODT-922 Fix panic during restarting the bridge.
+* GODT-945 Fix panic in integration tests caused by concurrent map writes.
 
 ### Changed
 * GODT-858 Bump go-rfc5322 dependency to v0.4.0 to handle some invalid RFC5322 groups.