diff --git a/lib/manifold/api/workspace.rb b/lib/manifold/api/workspace.rb
index 5b49db3..f760c67 100644
--- a/lib/manifold/api/workspace.rb
+++ b/lib/manifold/api/workspace.rb
@@ -26,6 +26,7 @@ def generate(path)
     end
 
     # Encapsulates a single manifold.
+    # rubocop:disable Metrics/ClassLength
     class Workspace
       attr_reader :name, :template_path, :logger
 
@@ -59,6 +60,7 @@ def generate(with_terraform: false)
 
         write_manifold_merge_sql
         write_dimensions_merge_sql
+        write_metrics_merge_sql
         generate_terraform
         logger.info("Generated Terraform configuration for workspace '#{name}'.")
       end
@@ -108,6 +110,16 @@ def write_dimensions_merge_sql
         write_dimensions_merge_sql_file(sql)
       end
 
+      def write_metrics_merge_sql
+        return unless manifold_file
+
+        @manifold_yaml["metrics"]&.each_key do |group_name|
+          sql_builder = Terraform::SQLBuilder.new(name, manifold_yaml)
+          sql = sql_builder.build_metric_merge_sql(group_name)
+          routines_directory.join("merge_#{group_name}.sql").write(sql)
+        end
+      end
+
       def valid_dimensions_config?
         return false unless manifold_yaml
 
@@ -152,5 +164,6 @@ def generate_terraform
         terraform_generator.generate(terraform_main_path)
       end
     end
+    # rubocop:enable Metrics/ClassLength
   end
 end
diff --git a/lib/manifold/templates/workspace_template.yml b/lib/manifold/templates/workspace_template.yml
index 0b25da6..26f8adb 100644
--- a/lib/manifold/templates/workspace_template.yml
+++ b/lib/manifold/templates/workspace_template.yml
@@ -61,3 +61,4 @@ metrics:
           field: context.sequence
 
     filter: timestamp >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 90 DAY)
+    source: my_project.events
diff --git a/lib/manifold/terraform/workspace_configuration.rb b/lib/manifold/terraform/workspace_configuration.rb
index f1a772f..5311ef2 100644
--- a/lib/manifold/terraform/workspace_configuration.rb
+++ b/lib/manifold/terraform/workspace_configuration.rb
@@ -1,7 +1,10 @@
 # frozen_string_literal: true
 
+# rubocop:disable Metrics/MethodLength, Metrics/AbcSize
+
 module Manifold
   module Terraform
+    # rubocop:disable Metrics/ClassLength
     # Handles building SQL for manifold routines
     class SQLBuilder
       def initialize(name, manifold_config)
@@ -33,6 +36,31 @@ def build_dimensions_merge_sql(source_sql)
         SQL
       end
 
+      def build_metric_merge_sql(group_name)
+        return "" unless valid_config? && @manifold_config["metrics"][group_name]
+
+        config = @manifold_config["metrics"][group_name]
+        ts_field = timestamp_field
+        interval = @manifold_config.dig("timestamp", "interval")
+        source = config["source"]
+        filter_clause = config["filter"] ? " WHERE #{config["filter"]}" : ""
+        metrics_struct = build_group_metrics_struct(group_name, config)
+        <<~SQL
+          MERGE #{@name}.#{metrics_table_name(group_name)} AS target
+          USING (
+            SELECT
+              id,
+              TIMESTAMP_TRUNC(#{ts_field}, #{interval}) AS timestamp,
+              STRUCT(#{metrics_struct}) AS metrics
+            FROM #{source}#{filter_clause}
+            GROUP BY id, timestamp
+          ) AS source
+          ON source.id = target.id AND source.timestamp = target.timestamp
+          WHEN MATCHED THEN UPDATE SET metrics = source.metrics
+          WHEN NOT MATCHED THEN INSERT ROW;
+        SQL
+      end
+
       private
 
       def valid_config?
@@ -106,7 +134,69 @@ def build_metric_joins
 
         "#{first}\n  #{joins.map { |table| "FULL OUTER JOIN #{table} USING (id, timestamp)" }.join("\n  ")}"
       end
+
+      # Builds the inner struct fields for a metrics group
+      def build_group_metrics_struct(_group_name, config)
+        condition_names = config["conditions"]&.keys || []
+        intersection_names = build_intersection_names(config)
+        field_names = condition_names + intersection_names
+        parts = field_names.map do |name|
+          expr = build_condition_expression(name, config)
+          aggregates = []
+          if config.dig("aggregations", "countif")
+            count_name = config["aggregations"]["countif"]
+            aggregates << "COUNTIF(#{expr}) AS #{count_name}"
+          end
+          if config.dig("aggregations", "sumif")
+            config["aggregations"]["sumif"].each do |metric, sum_cfg|
+              field = sum_cfg["field"]
+              aggregates << "SUM(IF(#{expr}, #{field}, 0)) AS #{metric}"
+            end
+          end
+          "STRUCT(#{aggregates.join(", ")}) AS #{name}"
+        end
+        parts.join(", ")
+      end
+
+      # Determines the condition expression, using a scalar function if args exist
+      def build_condition_expression(name, config)
+        cond_cfg = config["conditions"][name]
+        args = cond_cfg["args"]&.keys
+        if args && !args.empty?
+          "is#{name.capitalize}(#{args.join(", ")})"
+        else
+          cond_cfg["body"]
+        end
+      end
+
+      # Builds intersection condition names from breakouts
+      # rubocop:disable Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
+      def build_intersection_names(config)
+        breakouts = config["breakouts"] || {}
+        groups = breakouts.keys
+        return [] if groups.size <= 1
+
+        (2..groups.size).flat_map do |size|
+          groups.combination(size).flat_map do |combo|
+            condition_sets = combo.map { |g| breakouts[g] }
+            combos = condition_sets.first.map { |c| [c] }
+            combos = condition_sets[1..].reduce(combos) do |acc, set|
+              acc.flat_map { |prev| set.map { |c| prev + [c] } }
+            end
+            combos.map { |conds| format_intersection_name(conds) }
+          end
+        end
+      end
+      # rubocop:enable Metrics/AbcSize, Metrics/MethodLength, Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
+
+      # Formats intersection names (first lowercase, others capitalized)
+      def format_intersection_name(conds)
+        name = conds.first
+        conds[1..].each { |c| name += c.capitalize }
+        name
+      end
     end
+    # rubocop:enable Metrics/ClassLength
 
     # Handles building table configurations
     class TableConfigBuilder
@@ -223,16 +313,24 @@ def dataset_config
         }
       end
 
+      # rubocop:disable Metrics/MethodLength
       def routine_config
         routines = {
           "merge_dimensions" => dimensions_routine_attributes,
           "merge_manifold" => manifold_routine_attributes
         }.compact
+        # add metric merge routines
+        if @manifold_config&.dig("metrics")
+          @manifold_config["metrics"].each_key do |group|
+            routines["merge_#{group}"] = metric_routine_attributes(group)
+          end
+        end
         # add user-defined condition routines, if any
         conds = build_condition_routines
         routines.merge!(conds) unless conds.empty?
         routines.empty? ? nil : routines
       end
+      # rubocop:enable Metrics/MethodLength
 
       def dimensions_routine_attributes
         return nil if @vectors.empty? || @dimensions_config.nil?
@@ -260,6 +358,19 @@ def manifold_routine_attributes
         }
       end
 
+      # Builds attributes for a metric merge routine
+      def metric_routine_attributes(group_name)
+        {
+          "dataset_id" => name,
+          "project" => "${var.project_id}",
+          "routine_id" => "merge_#{group_name}",
+          "routine_type" => "PROCEDURE",
+          "language" => "SQL",
+          "definition_body" => "${file(\"${path.module}/routines/merge_#{group_name}.sql\")}",
+          "depends_on" => ["google_bigquery_dataset.#{name}"]
+        }
+      end
+
       # generate scalar function routines for defined conditions
       def build_condition_routines
         return {} unless @manifold_config.is_a?(Hash) && @manifold_config["metrics"].is_a?(Hash)
diff --git a/spec/manifold/api/workspace_spec.rb b/spec/manifold/api/workspace_spec.rb
index 68919c8..3770d4a 100644
--- a/spec/manifold/api/workspace_spec.rb
+++ b/spec/manifold/api/workspace_spec.rb
@@ -377,6 +377,15 @@ def parse_metrics_schema(group_name)
         expect(sql).to include("MERGE #{workspace.name}.Manifold AS target")
       end
 
+      it "generates metric merge SQL file for each metric group" do
+        expect(workspace.routines_directory.join("merge_taps.sql")).to be_file
+      end
+
+      it "includes the metric merge SQL in the generated file" do
+        sql = workspace.routines_directory.join("merge_taps.sql").read
+        expect(sql).to include("MERGE #{workspace.name}.TapsMetrics AS target")
+      end
+
       def configure_vector_service
         allow(Manifold::Services::VectorService).to receive(:new).and_return(vector_service)
         configure_vector_schema
diff --git a/spec/manifold/terraform/sql_builder_spec.rb b/spec/manifold/terraform/sql_builder_spec.rb
index 7d28803..a61c9ee 100644
--- a/spec/manifold/terraform/sql_builder_spec.rb
+++ b/spec/manifold/terraform/sql_builder_spec.rb
@@ -55,4 +55,59 @@
       expect(sql).to include("WHEN NOT MATCHED THEN INSERT ROW")
     end
   end
+
+  describe "#build_metric_merge_sql" do
+    subject(:sql) { builder.build_metric_merge_sql("renders") }
+
+    let(:manifold_config) do
+      {
+        "timestamp" => { "field" => "timestamp", "interval" => "DAY" },
+        "metrics" => {
+          "renders" => {
+            "source" => "my_project.events",
+            "filter" => "timestamp >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 7 DAY)",
+            "conditions" => {
+              "mobile" => { "args" => { "device" => "STRING" }, "body" => "device = 'mobile'" }
+            },
+            "aggregations" => {
+              "countif" => "renderCount",
+              "sumif" => { "seqSum" => { "field" => "context.seq" } }
+            }
+          }
+        }
+      }
+    end
+
+    it "merges into the renders metrics table" do
+      expect(sql).to include("MERGE analytics.RendersMetrics AS target")
+    end
+
+    it "truncates the timestamp field by interval" do
+      expect(sql).to include("TIMESTAMP_TRUNC(timestamp, DAY) AS timestamp")
+    end
+
+    it "uses the configured source" do
+      expect(sql).to include("FROM my_project.events")
+    end
+
+    it "uses the configured filter" do
+      expect(sql).to include("WHERE timestamp >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 7 DAY)")
+    end
+
+    it "groups by id and timestamp" do
+      expect(sql).to match(/GROUP BY id, timestamp/)
+    end
+
+    it "includes countif aggregation with condition expression" do
+      expect(sql).to include("COUNTIF(isMobile(device)) AS renderCount")
+    end
+
+    it "includes sumif aggregation with IF expression" do
+      expect(sql).to include("SUM(IF(isMobile(device), context.seq, 0)) AS seqSum")
+    end
+
+    it "updates on match and inserts on not match" do
+      expect(sql).to include("WHEN MATCHED THEN").and include("WHEN NOT MATCHED THEN INSERT ROW")
+    end
+  end
 end
diff --git a/spec/manifold/terraform/workspace_configuration_spec.rb b/spec/manifold/terraform/workspace_configuration_spec.rb
index 07ad7f7..857d6d3 100644
--- a/spec/manifold/terraform/workspace_configuration_spec.rb
+++ b/spec/manifold/terraform/workspace_configuration_spec.rb
@@ -109,11 +109,26 @@
         config.manifold_config = manifold_config
       end
 
+      let(:taps_routine) { json["resource"]["google_bigquery_routine"]["merge_taps"] }
+
       it "includes metrics table configurations" do
         expect(json["resource"]["google_bigquery_table"]).to include(
           "tapsmetrics" => expected_metrics_table("taps")
         )
       end
+
+      it "includes the merge_taps routine" do
+        routines = json["resource"]["google_bigquery_routine"]
+        expect(routines).to include("merge_taps")
+      end
+
+      it "sets the correct definition_body for merge_taps routine" do
+        expect(taps_routine["definition_body"]).to eq("${file(\"${path.module}/routines/merge_taps.sql\")}")
+      end
+
+      it "sets the routine_type for merge_taps routine" do
+        expect(taps_routine["routine_type"]).to eq("PROCEDURE")
+      end
     end
 
     context "when metric conditions are present" do