diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5b1c52b6..f1fa76a5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -36,14 +36,14 @@ ecbuild_add_option( FEATURE EXPERIMENTAL
 ecbuild_add_option( FEATURE GRIB
                     DEFAULT ON
                     DESCRIPTION "Add support for GRIB format"
-                    REQUIRED_PACKAGES "NAME eccodes VERSION 2.27" )
+                    REQUIRED_PACKAGES "NAME eccodes VERSION 2.46" )
 
 # BUFR support
 
 ecbuild_add_option( FEATURE BUFR
                     DEFAULT ON
                     DESCRIPTION "Add support for BUFR format"
-                    REQUIRED_PACKAGES "NAME eccodes VERSION 2.27" )
+                    REQUIRED_PACKAGES "NAME eccodes VERSION 2.46" )
 
 # netcdf support
 
diff --git a/VERSION b/VERSION
index b9a05a6d..84cc5294 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.17.3
+1.18.0
diff --git a/src/metkit/CMakeLists.txt b/src/metkit/CMakeLists.txt
index fe61d790..5fb6f064 100644
--- a/src/metkit/CMakeLists.txt
+++ b/src/metkit/CMakeLists.txt
@@ -25,10 +25,8 @@ list( APPEND metkit_srcs
     mars/DHSProtocol.h
     mars/Matcher.cc
     mars/Matcher.h
-    mars/MarsExpandContext.h
     mars/MarsExpansion.cc
     mars/MarsExpansion.h
-    mars/MarsExpension.h
     mars/MarsHandle.cc
     mars/MarsHandle.h
     mars/MarsLanguage.cc
diff --git a/src/metkit/mars/MarsExpandContext.h b/src/metkit/mars/MarsExpandContext.h
index 11f497ae..75554ed4 100644
--- a/src/metkit/mars/MarsExpandContext.h
+++ b/src/metkit/mars/MarsExpandContext.h
@@ -33,10 +33,4 @@ class MarsExpandContext {
 
 //----------------------------------------------------------------------------------------------------------------------
 
-class [[deprecated]] DummyContext : public MarsExpandContext {
-    using MarsExpandContext::MarsExpandContext;
-};
-
-//----------------------------------------------------------------------------------------------------------------------
-
 }  // namespace metkit::mars
diff --git a/src/metkit/mars/MarsExpansion.cc b/src/metkit/mars/MarsExpansion.cc
index 1f095617..f879d9c4 100644
--- a/src/metkit/mars/MarsExpansion.cc
+++ b/src/metkit/mars/MarsExpansion.cc
@@ -17,12 +17,6 @@ namespace metkit::mars {
 
 //----------------------------------------------------------------------------------------------------------------------
 
-FlattenCallback::~FlattenCallback() = default;
-
-ExpandCallback::~ExpandCallback() = default;
-
-//----------------------------------------------------------------------------------------------------------------------
-
 MarsExpansion::MarsExpansion(bool inherit, bool strict) : inherit_(inherit), strict_(strict) {}
 
 MarsExpansion::~MarsExpansion() {
@@ -37,7 +31,6 @@ void MarsExpansion::reset() {
     }
 }
 
-
 MarsLanguage& MarsExpansion::language(const std::string& verb) {
     auto v = MarsLanguage::expandVerb(verb);
 
@@ -64,28 +57,17 @@ std::vector<MarsRequest> MarsExpansion::expand(const std::vector<MarsParsedReque
 }
 
 MarsRequest MarsExpansion::expand(const MarsRequest& request) {
-    auto& lang = language(request.verb());
-    return lang.expand(request, inherit_, strict_);
+    return language(request.verb()).expand(request, inherit_, strict_);
 }
 
-
 void MarsExpansion::expand(const MarsRequest& request, ExpandCallback& callback) {
-    MarsRequest r = language(request.verb()).expand(request, inherit_, strict_);
-    callback(r);
+    callback(expand(request));
 }
 
-
 void MarsExpansion::flatten(const MarsRequest& request, FlattenCallback& callback) {
     language(request.verb()).flatten(request, callback);
 }
 
-void MarsExpansion::expand(const MarsExpandContext&, const MarsRequest& request, ExpandCallback& callback) {
-    expand(request, callback);
-}
-void MarsExpansion::flatten(const MarsExpandContext&, const MarsRequest& request, FlattenCallback& callback) {
-    flatten(request, callback);
-}
-
 //----------------------------------------------------------------------------------------------------------------------
 
 }  // namespace metkit::mars
diff --git a/src/metkit/mars/MarsExpansion.h b/src/metkit/mars/MarsExpansion.h
index b4a60fd9..70f3ff85 100644
--- a/src/metkit/mars/MarsExpansion.h
+++ b/src/metkit/mars/MarsExpansion.h
@@ -23,11 +23,9 @@
 #include <string>
 #include <vector>
 
-#include "metkit/mars/MarsExpandContext.h"
 #include "metkit/mars/MarsParsedRequest.h"
 #include "metkit/mars/MarsRequest.h"
 
-
 namespace metkit::mars {
 
 class MarsLanguage;
@@ -37,16 +35,21 @@ class MarsLanguage;
 class FlattenCallback {
 public:
 
-    virtual ~FlattenCallback();
     virtual void operator()(const MarsRequest&) = 0;
+
+protected:
+
+    virtual ~FlattenCallback() = default;
 };
 
 class ExpandCallback {
 public:
 
-    virtual ~ExpandCallback();
-    virtual void operator()(const MarsRequest& request) { this->operator()(DummyContext{}, request); }
-    virtual void operator()(const MarsExpandContext&, const MarsRequest&) = 0;
+    virtual void operator()(const MarsRequest&) = 0;
+
+protected:
+
+    virtual ~ExpandCallback() = default;
 };
 
 //----------------------------------------------------------------------------------------------------------------------
@@ -63,9 +66,7 @@ class MarsExpansion : public eckit::NonCopyable {
     std::vector<MarsRequest> expand(const std::vector<MarsParsedRequest>&);
 
     void expand(const MarsRequest&, ExpandCallback&);
-    void expand(const MarsExpandContext&, const MarsRequest&, ExpandCallback&);
     void flatten(const MarsRequest&, FlattenCallback&);
-    void flatten(const MarsExpandContext&, const MarsRequest&, FlattenCallback&);
 
 private:
 
diff --git a/src/metkit/mars/MarsExpension.h b/src/metkit/mars/MarsExpension.h
deleted file mode 100644
index b76a7a36..00000000
--- a/src/metkit/mars/MarsExpension.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/*
- * (C) Copyright 1996- ECMWF.
- *
- * This software is licensed under the terms of the Apache Licence Version 2.0
- * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
- * In applying this licence, ECMWF does not waive the privileges and immunities
- * granted to it by virtue of its status as an intergovernmental organisation nor
- * does it submit to any jurisdiction.
- */
-
-#ifndef metkit_MarsExpension_H
-#define metkit_MarsExpension_H
-
-#include "metkit/mars/MarsExpansion.h"
-
-namespace metkit::mars {
-
-//----------------------------------------------------------------------------------------------------------------------
-
-struct [[deprecated("Use MarsExpansion instead")]] MarsExpension : MarsExpansion {
-    using MarsExpansion::MarsExpansion;
-};
-
-//----------------------------------------------------------------------------------------------------------------------
-
-}  // namespace metkit::mars
-
-#endif
diff --git a/src/metkit/mars/MarsLanguage.cc b/src/metkit/mars/MarsLanguage.cc
index a22076de..ce6f2bc5 100644
--- a/src/metkit/mars/MarsLanguage.cc
+++ b/src/metkit/mars/MarsLanguage.cc
@@ -100,12 +100,12 @@ void MarsLanguage::parseModifier(ModifierType typ, std::shared_ptr<Context> ctx,
     }
 }
 
-MarsLanguage::MarsLanguage(const std::string& verb) : verb_(verb) {
+MarsLanguage::MarsLanguage(const std::string& verb) {
     pthread_once(&once, init);
 
-    eckit::Value lang   = languages_[verb];
-    eckit::Value params = lang.keys();
-
+    verb_                = MarsLanguage::expandVerb(verb);
+    eckit::Value lang    = languages_[verb_];
+    eckit::Value params  = lang.keys();
     eckit::Value options = lang["_options"];
 
     for (size_t i = 0; i < params.size(); ++i) {
diff --git a/src/metkit/mars/MarsParser.cc b/src/metkit/mars/MarsParser.cc
index e715561e..d4145c12 100644
--- a/src/metkit/mars/MarsParser.cc
+++ b/src/metkit/mars/MarsParser.cc
@@ -15,8 +15,6 @@
 
 #include "metkit/mars/MarsParser.h"
 
-#include "metkit/mars/MarsExpandContext.h"
-
 namespace metkit::mars {
 
 //----------------------------------------------------------------------------------------------------------------------
@@ -200,7 +198,7 @@ void MarsParser::parse(MarsParserCallback& cb) {
 
     while (peek() != 0) {
         auto r = parseRequest();
-        cb(DummyContext{}, r);
+        cb(r);
     }
 }
 
diff --git a/src/metkit/mars/MarsParser.h b/src/metkit/mars/MarsParser.h
index 5d6f2a47..c12cb56e 100644
--- a/src/metkit/mars/MarsParser.h
+++ b/src/metkit/mars/MarsParser.h
@@ -19,27 +19,22 @@
 
 namespace metkit::mars {
 
-class MarsExpandContext;
 class MarsRequest;
 
-
 //----------------------------------------------------------------------------------------------------------------------
 
-
 class MarsParserCallback {
 public:
 
-    virtual void operator()(const MarsExpandContext&, const MarsRequest&) = 0;
+    virtual void operator()(const MarsRequest&) = 0;
 
 protected:
 
     virtual ~MarsParserCallback() = default;
 };
 
-
 //----------------------------------------------------------------------------------------------------------------------
 
-
 class MarsParser : public eckit::StreamParser {
 
 public:  // methods
diff --git a/src/metkit/mars/MarsRequest.cc b/src/metkit/mars/MarsRequest.cc
index d1b646d4..83e28361 100644
--- a/src/metkit/mars/MarsRequest.cc
+++ b/src/metkit/mars/MarsRequest.cc
@@ -30,7 +30,9 @@ namespace mars {
 
 MarsRequest::MarsRequest() {}
 
-MarsRequest::MarsRequest(const std::string& s) : verb_(s) {}
+MarsRequest::MarsRequest(const std::string& s) : verb_(s) {
+    ASSERT(s.find(',') == std::string::npos);
+}
 
 MarsRequest::MarsRequest(const std::string& s, const std::map<std::string, std::string>& values) : verb_(s) {
     for (auto j = values.begin(); j != values.end(); ++j) {
diff --git a/src/metkit/mars/Type.cc b/src/metkit/mars/Type.cc
index eec42e4c..fe309e80 100644
--- a/src/metkit/mars/Type.cc
+++ b/src/metkit/mars/Type.cc
@@ -269,9 +269,6 @@ bool Type::expand(std::string& value, const MarsRequest&) const {
     oss << *this << ":  expand not implemented (" << value << ")";
     throw eckit::SeriousBug(oss.str());
 }
-bool Type::expand(const MarsExpandContext&, std::string& value, const MarsRequest& request) const {
-    return expand(value, request);
-}
 
 void Type::expand(std::vector<std::string>& values, const MarsRequest& request) const {
 
diff --git a/src/metkit/mars/Type.h b/src/metkit/mars/Type.h
index 67f7c5dc..d55c59e1 100644
--- a/src/metkit/mars/Type.h
+++ b/src/metkit/mars/Type.h
@@ -30,8 +30,6 @@
 
 namespace metkit::mars {
 
-class MarsExpandContext;
-
 //----------------------------------------------------------------------------------------------------------------------
 
 /// @brief abstract class - ContextRule subclasses are used to define a context. A MarsRequest matches a context, if it
@@ -192,7 +190,6 @@ class Type : public eckit::Counted {
     ~Type() noexcept override = default;
 
     virtual bool expand(std::string& value, const MarsRequest& request = {}) const;
-    [[deprecated]] bool expand(const MarsExpandContext& ctx, std::string& value, const MarsRequest& request = {}) const;
     void expand(std::vector<std::string>& values, const MarsRequest& request = {}) const;
 
     std::string tidy(const std::string& value, const MarsRequest& request = {}) const;
diff --git a/src/tools/parse-mars-request.cc b/src/tools/parse-mars-request.cc
index 52361e91..a67dc567 100644
--- a/src/tools/parse-mars-request.cc
+++ b/src/tools/parse-mars-request.cc
@@ -157,17 +157,6 @@ void ParseRequest::process(const eckit::PathName& path) {
             }
         }
     }
-
-    class Print : public FlattenCallback {
-        virtual void operator()(const MarsRequest& request) { std::cout << request << std::endl; }
-    };
-
-
-    Print cb;
-
-    // for (std::vector<MarsRequest>::const_iterator j = v.begin(); j != v.end(); ++j) {
-    //     expand.flatten(*j, cb, filter);
-    // }
 }
 
 //----------------------------------------------------------------------------------------------------------------------