diff --git a/package.json b/package.json
index 5fecf69bab..f2e79709dc 100644
--- a/package.json
+++ b/package.json
@@ -10,7 +10,7 @@
     "dev:desktop": "bun --cwd packages/desktop dev",
     "dev:web": "bun --cwd packages/app dev",
     "dev:console": "ulimit -n 10240 2>/dev/null; bun run --cwd packages/console/app dev",
-    "dev:stats": "bun sst shell --stage=production -- bun run --cwd packages/stats/app dev",
+    "dev:stats": "bun sst shell --stage=dev -- bun run --cwd packages/stats/app dev",
     "dev:storybook": "bun --cwd packages/storybook storybook",
     "lint": "oxlint",
     "typecheck": "bun turbo typecheck",
diff --git a/packages/stats/core/src/honeycomb-backfill.ts b/packages/stats/core/src/honeycomb-backfill.ts
index 2b497bdf9e..93fc237e97 100644
--- a/packages/stats/core/src/honeycomb-backfill.ts
+++ b/packages/stats/core/src/honeycomb-backfill.ts
@@ -19,11 +19,11 @@ import {
   statPeriodKey,
   synthesizeAllTierRows,
   toStatBaseRow,
-  UPSERT_CHUNK_SIZE,
   type StatBaseAggregate,
 } from "./domain/stat"
 
 const DAY_MS = 86_400_000
+const DEFAULT_UPSERT_CHUNK_SIZE = 100
 const DEFAULT_TIERS = ["Go", "Free", "Paid"]
 const FREE_MODELS = new Set(["gpt-5-nano", "grok-code", "big-pickle"])
 
@@ -44,6 +44,7 @@ type ImportOptions = {
   directories: string[]
   dryRun: boolean
   periodStart: Date | undefined
+  upsertChunkSize: number
   files: Partial<Record<ImportKey, string[]>>
 }
 type ModelAggregate = StatBaseAggregate & { provider: string; model: string; provider_model: string }
@@ -168,6 +169,7 @@ async function importFiles(args: string[]) {
         providerRows: providerRows.length,
         geoRows: geoRows.length,
         dryRun: opts.dryRun,
+        upsertChunkSize: opts.upsertChunkSize,
       },
       null,
       2,
@@ -178,9 +180,9 @@ async function importFiles(args: string[]) {
   if (!opts.databaseUrl) fail("DATABASE_URL is required unless --dry-run is set")
 
   const db = drizzle({ client: new Client({ url: opts.databaseUrl }) })
-  await upsertModelRows(db, modelRows)
-  await upsertProviderRows(db, providerRows)
-  await upsertGeoRows(db, geoRows)
+  await upsertModelRows(db, modelRows, opts.upsertChunkSize)
+  await upsertProviderRows(db, providerRows, opts.upsertChunkSize)
+  await upsertGeoRows(db, geoRows, opts.upsertChunkSize)
 }
 
 function buildQueries(limit: number, tiers: string[]): QuerySpec[] {
@@ -783,125 +785,125 @@ function isRecord(value: unknown): value is Record<string, unknown> {
   return typeof value === "object" && value !== null && !Array.isArray(value)
 }
 
-async function upsertModelRows(db: ReturnType<typeof drizzle>, rows: ModelStatRow[]) {
-  await Promise.all(
-    chunks(rows, UPSERT_CHUNK_SIZE).map((chunk) =>
-      db
-        .insert(modelStat)
-        .values(chunk)
-        .onDuplicateKeyUpdate({
-          set: {
-            provider_model: inserted("provider_model"),
-            sessions: inserted("sessions"),
-            requests: inserted("requests"),
-            input_tokens: inserted("input_tokens"),
-            output_tokens: inserted("output_tokens"),
-            reasoning_tokens: inserted("reasoning_tokens"),
-            cache_read_tokens: inserted("cache_read_tokens"),
-            total_tokens: inserted("total_tokens"),
-            input_cost_microcents: inserted("input_cost_microcents"),
-            output_cost_microcents: inserted("output_cost_microcents"),
-            total_cost_microcents: inserted("total_cost_microcents"),
-            avg_duration_ms: inserted("avg_duration_ms"),
-            p50_duration_ms: inserted("p50_duration_ms"),
-            p95_duration_ms: inserted("p95_duration_ms"),
-            avg_ttfb_ms: inserted("avg_ttfb_ms"),
-            p50_ttfb_ms: inserted("p50_ttfb_ms"),
-            p95_ttfb_ms: inserted("p95_ttfb_ms"),
-            avg_output_tps: inserted("avg_output_tps"),
-            success_count: inserted("success_count"),
-            error_count: inserted("error_count"),
-            sample_count: inserted("sample_count"),
-            rank_by_tokens: inserted("rank_by_tokens"),
-            rank_by_requests: inserted("rank_by_requests"),
-            rank_by_cost: inserted("rank_by_cost"),
-          },
-        }),
-    ),
-  )
+async function upsertModelRows(db: ReturnType<typeof drizzle>, rows: ModelStatRow[], chunkSize: number) {
+  const batches = chunks(rows, chunkSize)
+  console.log(JSON.stringify({ table: "model_stat", batches: batches.length, chunkSize }))
+  for (const chunk of batches) {
+    await db
+      .insert(modelStat)
+      .values(chunk)
+      .onDuplicateKeyUpdate({
+        set: {
+          provider_model: inserted("provider_model"),
+          sessions: inserted("sessions"),
+          requests: inserted("requests"),
+          input_tokens: inserted("input_tokens"),
+          output_tokens: inserted("output_tokens"),
+          reasoning_tokens: inserted("reasoning_tokens"),
+          cache_read_tokens: inserted("cache_read_tokens"),
+          total_tokens: inserted("total_tokens"),
+          input_cost_microcents: inserted("input_cost_microcents"),
+          output_cost_microcents: inserted("output_cost_microcents"),
+          total_cost_microcents: inserted("total_cost_microcents"),
+          avg_duration_ms: inserted("avg_duration_ms"),
+          p50_duration_ms: inserted("p50_duration_ms"),
+          p95_duration_ms: inserted("p95_duration_ms"),
+          avg_ttfb_ms: inserted("avg_ttfb_ms"),
+          p50_ttfb_ms: inserted("p50_ttfb_ms"),
+          p95_ttfb_ms: inserted("p95_ttfb_ms"),
+          avg_output_tps: inserted("avg_output_tps"),
+          success_count: inserted("success_count"),
+          error_count: inserted("error_count"),
+          sample_count: inserted("sample_count"),
+          rank_by_tokens: inserted("rank_by_tokens"),
+          rank_by_requests: inserted("rank_by_requests"),
+          rank_by_cost: inserted("rank_by_cost"),
+        },
+      })
+  }
 }
 
-async function upsertProviderRows(db: ReturnType<typeof drizzle>, rows: ProviderStatRow[]) {
-  await Promise.all(
-    chunks(rows, UPSERT_CHUNK_SIZE).map((chunk) =>
-      db
-        .insert(providerStat)
-        .values(chunk)
-        .onDuplicateKeyUpdate({
-          set: {
-            sessions: inserted("sessions"),
-            requests: inserted("requests"),
-            input_tokens: inserted("input_tokens"),
-            output_tokens: inserted("output_tokens"),
-            reasoning_tokens: inserted("reasoning_tokens"),
-            cache_read_tokens: inserted("cache_read_tokens"),
-            total_tokens: inserted("total_tokens"),
-            input_cost_microcents: inserted("input_cost_microcents"),
-            output_cost_microcents: inserted("output_cost_microcents"),
-            total_cost_microcents: inserted("total_cost_microcents"),
-            avg_duration_ms: inserted("avg_duration_ms"),
-            p50_duration_ms: inserted("p50_duration_ms"),
-            p95_duration_ms: inserted("p95_duration_ms"),
-            avg_ttfb_ms: inserted("avg_ttfb_ms"),
-            p50_ttfb_ms: inserted("p50_ttfb_ms"),
-            p95_ttfb_ms: inserted("p95_ttfb_ms"),
-            avg_output_tps: inserted("avg_output_tps"),
-            success_count: inserted("success_count"),
-            error_count: inserted("error_count"),
-            sample_count: inserted("sample_count"),
-            market_share_tokens: inserted("market_share_tokens"),
-            market_share_requests: inserted("market_share_requests"),
-            market_share_sessions: inserted("market_share_sessions"),
-            rank_by_tokens: inserted("rank_by_tokens"),
-            rank_by_requests: inserted("rank_by_requests"),
-            rank_by_sessions: inserted("rank_by_sessions"),
-            rank_by_cost: inserted("rank_by_cost"),
-          },
-        }),
-    ),
-  )
+async function upsertProviderRows(db: ReturnType<typeof drizzle>, rows: ProviderStatRow[], chunkSize: number) {
+  const batches = chunks(rows, chunkSize)
+  console.log(JSON.stringify({ table: "provider_stat", batches: batches.length, chunkSize }))
+  for (const chunk of batches) {
+    await db
+      .insert(providerStat)
+      .values(chunk)
+      .onDuplicateKeyUpdate({
+        set: {
+          sessions: inserted("sessions"),
+          requests: inserted("requests"),
+          input_tokens: inserted("input_tokens"),
+          output_tokens: inserted("output_tokens"),
+          reasoning_tokens: inserted("reasoning_tokens"),
+          cache_read_tokens: inserted("cache_read_tokens"),
+          total_tokens: inserted("total_tokens"),
+          input_cost_microcents: inserted("input_cost_microcents"),
+          output_cost_microcents: inserted("output_cost_microcents"),
+          total_cost_microcents: inserted("total_cost_microcents"),
+          avg_duration_ms: inserted("avg_duration_ms"),
+          p50_duration_ms: inserted("p50_duration_ms"),
+          p95_duration_ms: inserted("p95_duration_ms"),
+          avg_ttfb_ms: inserted("avg_ttfb_ms"),
+          p50_ttfb_ms: inserted("p50_ttfb_ms"),
+          p95_ttfb_ms: inserted("p95_ttfb_ms"),
+          avg_output_tps: inserted("avg_output_tps"),
+          success_count: inserted("success_count"),
+          error_count: inserted("error_count"),
+          sample_count: inserted("sample_count"),
+          market_share_tokens: inserted("market_share_tokens"),
+          market_share_requests: inserted("market_share_requests"),
+          market_share_sessions: inserted("market_share_sessions"),
+          rank_by_tokens: inserted("rank_by_tokens"),
+          rank_by_requests: inserted("rank_by_requests"),
+          rank_by_sessions: inserted("rank_by_sessions"),
+          rank_by_cost: inserted("rank_by_cost"),
+        },
+      })
+  }
 }
 
-async function upsertGeoRows(db: ReturnType<typeof drizzle>, rows: GeoStatRow[]) {
-  await Promise.all(
-    chunks(rows, UPSERT_CHUNK_SIZE).map((chunk) =>
-      db
-        .insert(geoStat)
-        .values(chunk)
-        .onDuplicateKeyUpdate({
-          set: {
-            continent: inserted("continent"),
-            sessions: inserted("sessions"),
-            requests: inserted("requests"),
-            input_tokens: inserted("input_tokens"),
-            output_tokens: inserted("output_tokens"),
-            reasoning_tokens: inserted("reasoning_tokens"),
-            cache_read_tokens: inserted("cache_read_tokens"),
-            total_tokens: inserted("total_tokens"),
-            input_cost_microcents: inserted("input_cost_microcents"),
-            output_cost_microcents: inserted("output_cost_microcents"),
-            total_cost_microcents: inserted("total_cost_microcents"),
-            avg_duration_ms: inserted("avg_duration_ms"),
-            p50_duration_ms: inserted("p50_duration_ms"),
-            p95_duration_ms: inserted("p95_duration_ms"),
-            avg_ttfb_ms: inserted("avg_ttfb_ms"),
-            p50_ttfb_ms: inserted("p50_ttfb_ms"),
-            p95_ttfb_ms: inserted("p95_ttfb_ms"),
-            avg_output_tps: inserted("avg_output_tps"),
-            success_count: inserted("success_count"),
-            error_count: inserted("error_count"),
-            sample_count: inserted("sample_count"),
-            market_share_tokens: inserted("market_share_tokens"),
-            market_share_requests: inserted("market_share_requests"),
-            market_share_sessions: inserted("market_share_sessions"),
-            rank_by_tokens: inserted("rank_by_tokens"),
-            rank_by_requests: inserted("rank_by_requests"),
-            rank_by_sessions: inserted("rank_by_sessions"),
-            rank_by_cost: inserted("rank_by_cost"),
-          },
-        }),
-    ),
-  )
+async function upsertGeoRows(db: ReturnType<typeof drizzle>, rows: GeoStatRow[], chunkSize: number) {
+  const batches = chunks(rows, chunkSize)
+  console.log(JSON.stringify({ table: "geo_stat", batches: batches.length, chunkSize }))
+  for (const chunk of batches) {
+    await db
+      .insert(geoStat)
+      .values(chunk)
+      .onDuplicateKeyUpdate({
+        set: {
+          continent: inserted("continent"),
+          sessions: inserted("sessions"),
+          requests: inserted("requests"),
+          input_tokens: inserted("input_tokens"),
+          output_tokens: inserted("output_tokens"),
+          reasoning_tokens: inserted("reasoning_tokens"),
+          cache_read_tokens: inserted("cache_read_tokens"),
+          total_tokens: inserted("total_tokens"),
+          input_cost_microcents: inserted("input_cost_microcents"),
+          output_cost_microcents: inserted("output_cost_microcents"),
+          total_cost_microcents: inserted("total_cost_microcents"),
+          avg_duration_ms: inserted("avg_duration_ms"),
+          p50_duration_ms: inserted("p50_duration_ms"),
+          p95_duration_ms: inserted("p95_duration_ms"),
+          avg_ttfb_ms: inserted("avg_ttfb_ms"),
+          p50_ttfb_ms: inserted("p50_ttfb_ms"),
+          p95_ttfb_ms: inserted("p95_ttfb_ms"),
+          avg_output_tps: inserted("avg_output_tps"),
+          success_count: inserted("success_count"),
+          error_count: inserted("error_count"),
+          sample_count: inserted("sample_count"),
+          market_share_tokens: inserted("market_share_tokens"),
+          market_share_requests: inserted("market_share_requests"),
+          market_share_sessions: inserted("market_share_sessions"),
+          rank_by_tokens: inserted("rank_by_tokens"),
+          rank_by_requests: inserted("rank_by_requests"),
+          rank_by_sessions: inserted("rank_by_sessions"),
+          rank_by_cost: inserted("rank_by_cost"),
+        },
+      })
+  }
 }
 
 function parseImportOptions(args: string[]): ImportOptions {
@@ -917,6 +919,7 @@ function parseImportOptions(args: string[]): ImportOptions {
     directories: flags.get("dir") ?? flags.get("directory") ?? [],
     dryRun: flags.has("dry-run"),
     periodStart: parseDateFlag(flags, "period-start"),
+    upsertChunkSize: parseIntegerFlag(flags, "upsert-chunk-size") ?? DEFAULT_UPSERT_CHUNK_SIZE,
     files,
   }
 }
@@ -969,8 +972,8 @@ function parseListFlag(flags: Map<string, string[]>, name: string) {
 function usage(): never {
   fail(`Usage:
   bun src/honeycomb-backfill.ts queries [--tiers Go,Free,Paid] [--limit 1000]
-  bun src/honeycomb-backfill.ts import [--dry-run] [--database-url URL] --dir downloads
-  bun src/honeycomb-backfill.ts import [--dry-run] [--database-url URL] --model-day file.csv [--model-day more.csv] ...`)
+  bun src/honeycomb-backfill.ts import [--dry-run] [--upsert-chunk-size 100] [--database-url URL] --dir downloads
+  bun src/honeycomb-backfill.ts import [--dry-run] [--upsert-chunk-size 100] [--database-url URL] --model-day file.csv [--model-day more.csv] ...`)
 }
 
 function fail(message: string): never {