diff --git a/build.go b/build.go
index dddc3b964..b3b7f5eee 100644
--- a/build.go
+++ b/build.go
@@ -380,6 +380,12 @@ func main() {
 		}
 	}
 
+	solarisMinVersion := GoVersion{Major: 1, Minor: 20, Patch: 0}
+	if env["GOARCH"] == "solaris" && !goVersion.AtLeast(solarisMinVersion) {
+		fmt.Fprintf(os.Stderr, "Detected version %s is too old, restic requires at least %s for Solaris\n", goVersion, solarisMinVersion)
+		os.Exit(1)
+	}
+
 	verbosePrintf("detected Go version %v\n", goVersion)
 
 	preserveSymbols := false
diff --git a/changelog/unreleased/pull-4201 b/changelog/unreleased/pull-4201
new file mode 100644
index 000000000..500bbdbb1
--- /dev/null
+++ b/changelog/unreleased/pull-4201
@@ -0,0 +1,9 @@
+Change: Require Go 1.20 for Solaris builds
+
+Building restic on Solaris now requires Go 1.20, as the library used to access
+Azure uses the mmap syscall, which is only available on Solaris starting from
+Go 1.20.
+
+All other platforms continue to build with Go 1.18.
+
+https://github.com/restic/restic/pull/4201
diff --git a/doc/020_installation.rst b/doc/020_installation.rst
index 4488e31f9..4d591356d 100644
--- a/doc/020_installation.rst
+++ b/doc/020_installation.rst
@@ -269,7 +269,8 @@ From Source
 ***********
 
 restic is written in the Go programming language and you need at least
-Go version 1.18. Building restic may also work with older versions of Go,
+Go version 1.18. Building for Solaris requires at least Go version 1.20.
+Building restic may also work with older versions of Go,
 but that's not supported. See the `Getting
 started <https://go.dev/doc/install>`__ guide of the Go project for
 instructions how to install Go.
diff --git a/go.mod b/go.mod
index d0e514220..752e88019 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@ module github.com/restic/restic
 require (
 	cloud.google.com/go/storage v1.30.1
 	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.4.0
-	github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v0.5.1
+	github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v1.0.0
 	github.com/anacrolix/fuse v0.2.0
 	github.com/cenkalti/backoff/v4 v4.2.0
 	github.com/cespare/xxhash/v2 v2.2.0
diff --git a/go.sum b/go.sum
index ce664c15a..493f95aad 100644
--- a/go.sum
+++ b/go.sum
@@ -15,8 +15,8 @@ github.com/Azure/azure-sdk-for-go/sdk/azcore v1.4.0/go.mod h1:ON4tFdPTwRcgWEaVDr
 github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.1.0 h1:QkAcEIAKbNL4KoFr4SathZPhDhF4mVwpBMFlYjyAqy8=
 github.com/Azure/azure-sdk-for-go/sdk/internal v1.1.2 h1:+5VZ72z0Qan5Bog5C+ZkgSqUbeVUd9wgtHOrIKuc5b8=
 github.com/Azure/azure-sdk-for-go/sdk/internal v1.1.2/go.mod h1:eWRD7oawr1Mu1sLCawqVc0CUiF43ia3qQMxLscsKQ9w=
-github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v0.5.1 h1:BMTdr+ib5ljLa9MxTJK8x/Ds0MbBb4MfuW5BL0zMJnI=
-github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v0.5.1/go.mod h1:c6WvOhtmjNUWbLfOG1qxM/q0SPvQNSVJvolm+C52dIU=
+github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v1.0.0 h1:u/LLAOFgsMv7HmNL4Qufg58y+qElGOt5qv0z1mURkRY=
+github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v1.0.0/go.mod h1:2e8rMJtl2+2j+HXbTBwnyGpm5Nou7KhvSfxOq8JpTag=
 github.com/AzureAD/microsoft-authentication-library-for-go v0.5.1 h1:BWe8a+f/t+7KY7zH2mqygeUD0t8hNFXe08p1Pb3/jKE=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/Julusian/godocdown v0.0.0-20170816220326-6d19f8ff2df8/go.mod h1:INZr5t32rG59/5xeltqoCJoNY7e5x/3xoY9WSWVWg74=
diff --git a/internal/backend/azure/azure.go b/internal/backend/azure/azure.go
index 02433795b..c92fa3f89 100644
--- a/internal/backend/azure/azure.go
+++ b/internal/backend/azure/azure.go
@@ -228,7 +228,7 @@ func (be *Backend) saveSmall(ctx context.Context, objName string, rd restic.Rewi
 
 	reader := bytes.NewReader(buf)
 	_, err = blockBlobClient.StageBlock(ctx, id, streaming.NopCloser(reader), &blockblob.StageBlockOptions{
-		TransactionalContentMD5: rd.Hash(),
+		TransactionalValidation: blob.TransferValidationTypeMD5(rd.Hash()),
 	})
 	if err != nil {
 		return errors.Wrap(err, "StageBlock")
@@ -271,7 +271,7 @@ func (be *Backend) saveLarge(ctx context.Context, objName string, rd restic.Rewi
 		reader := bytes.NewReader(buf)
 		debug.Log("StageBlock %v with %d bytes", id, len(buf))
 		_, err = blockBlobClient.StageBlock(ctx, id, streaming.NopCloser(reader), &blockblob.StageBlockOptions{
-			TransactionalContentMD5: h[:],
+			TransactionalValidation: blob.TransferValidationTypeMD5(h[:]),
 		})
 
 		if err != nil {