refactor: eliminate small-package smell

.gitignore

@@ -1,7 +1,6 @@
 # Build output
-/build/
+/bin/
 
 # Local development
 .claude/
 agent/
-charon

Makefile

@@ -1,14 +1,7 @@
-BINARY     := charon
-CMD        := ./cmd/charon
-BUILD_DIR  := ./build
+BIN_DIR    := ./bin
 IMAGE_NAME ?= charon
 IMAGE_TAG  ?= latest
 
-GOOS   ?= $(shell go env GOOS)
-GOARCH ?= $(shell go env GOARCH)
-
-OUT := $(BUILD_DIR)/$(GOOS)/$(GOARCH)/$(BINARY)
-
 OPENRESPONSES_DIR ?= ../openresponses
 
 .PHONY: all fmt fmt-check vet lint presubmit test test-unit test-integration test-compliance test-disruptive test-system test-compliance-bun tidy update build image clean
@@ -86,11 +79,12 @@ update:
 # ── Build & package ───────────────────────────────────────────────────────────
 
 build:
-	mkdir -p $(BUILD_DIR)/$(GOOS)/$(GOARCH)
-	go build -o $(OUT) $(CMD)
+	mkdir -p $(BIN_DIR)
+	go build -o $(BIN_DIR)/charon ./cmd/charon
+	go build -o $(BIN_DIR)/proxy ./cmd/proxy
 
 image:
 	docker build -t $(IMAGE_NAME):$(IMAGE_TAG) .
 
 clean:
-	rm -rf $(BUILD_DIR)
+	rm -rf $(BIN_DIR)

cmd/charon/main.go

@@ -14,8 +14,7 @@ import (
 
 	"github.com/elevran/charon/internal/chainstore"
 	pebblebe "github.com/elevran/charon/internal/chainstore/pebble"
-	"github.com/elevran/charon/internal/config"
-	"github.com/elevran/charon/internal/metrics"
+	"github.com/elevran/charon/internal/charonconfig"
 	"github.com/elevran/charon/internal/server"
 	"github.com/elevran/charon/internal/telemetry"
 )
@@ -29,7 +28,7 @@ func main() {
 func run() error {
 	log := slog.New(slog.NewJSONHandler(os.Stdout, nil))
 
-	opts := config.NewCharonOptions()
+	opts := charonconfig.NewOptions()
 	fs := flag.NewFlagSet("charon", flag.ExitOnError)
 	opts.AddFlags(fs)
 	_ = fs.Parse(os.Args[1:])
@@ -43,7 +42,7 @@ func run() error {
 	}
 
 	reg := prometheus.NewRegistry()
-	if err := metrics.Register(reg, ""); err != nil {
+	if err := server.RegisterMetrics(reg, ""); err != nil {
 		log.Error("register metrics", "err", err)
 		return err
 	}

cmd/charon/main_test.go

@@ -6,11 +6,11 @@ import (
 
 	"github.com/stretchr/testify/require"
 
-	"github.com/elevran/charon/internal/config"
+	"github.com/elevran/charon/internal/charonconfig"
 )
 
 func TestConfigDefaults(t *testing.T) {
-	opts := config.NewCharonOptions()
+	opts := charonconfig.NewOptions()
 	require.Equal(t, ":8081", opts.Listen)
 	require.Equal(t, 30, opts.TTLDays)
 }

cmd/proxy/assemble.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
 )
 
 // marshalStoredResponse serialises an inference response and request metadata

cmd/proxy/assemble_test.go

@@ -5,7 +5,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
 )
 
 // helper: decode json.RawMessage value for a key from map.

cmd/proxy/disruptive_test.go

@@ -26,7 +26,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
 )
 
 // failingCharonMux returns an http.Handler that returns 507 for all PUT

cmd/proxy/handler.go

@@ -8,8 +8,8 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/elevran/charon/internal/httputil"
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
+	"github.com/elevran/charon/internal/server"
 	"github.com/elevran/charon/pkg/charon"
 )
 
@@ -46,23 +46,23 @@ func RegisterHandlers(mux *http.ServeMux, h *Handler) {
 func (h *Handler) HandleCreate(w http.ResponseWriter, r *http.Request) {
 	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
-		httputil.WriteError(w, http.StatusBadRequest, "failed to read request body")
+		server.WriteError(w, http.StatusBadRequest, "failed to read request body")
 		return
 	}
 
 	var req CreateRequest
 	if err := json.Unmarshal(bodyBytes, &req); err != nil {
-		httputil.WriteError(w, http.StatusBadRequest, "invalid request body")
+		server.WriteError(w, http.StatusBadRequest, "invalid request body")
 		return
 	}
 	if req.Model == "" {
-		httputil.WriteError(w, http.StatusBadRequest, "model is required")
+		server.WriteError(w, http.StatusBadRequest, "model is required")
 		return
 	}
 
 	var rawReq map[string]json.RawMessage
 	if err := json.Unmarshal(bodyBytes, &rawReq); err != nil {
-		httputil.WriteError(w, http.StatusBadRequest, "invalid request body")
+		server.WriteError(w, http.StatusBadRequest, "invalid request body")
 		return
 	}
 
@@ -76,7 +76,7 @@ func (h *Handler) HandleCreate(w http.ResponseWriter, r *http.Request) {
 
 	inputItems, err := inputToItems(req.Input)
 	if err != nil {
-		httputil.WriteError(w, http.StatusBadRequest, "invalid input")
+		server.WriteError(w, http.StatusBadRequest, "invalid input")
 		return
 	}
 
@@ -101,7 +101,7 @@ func (h *Handler) HandleCreate(w http.ResponseWriter, r *http.Request) {
 	infResp, err := h.inf.Complete(ctx, infMap)
 	if err != nil {
 		h.log.Error("inference complete", "err", err)
-		httputil.WriteError(w, http.StatusBadGateway, "inference error")
+		server.WriteError(w, http.StatusBadGateway, "inference error")
 		return
 	}
 	completedAt := time.Now()
@@ -110,13 +110,13 @@ func (h *Handler) HandleCreate(w http.ResponseWriter, r *http.Request) {
 		responseBlob := marshalStoredResponse(infResp, req.PreviousResponseID, req.Instructions, req.Background)
 		if err := h.charon.Store(ctx, infResp.ID, stagingID, tenantKey, responseBlob); err != nil {
 			h.log.Error("charon store", "id", infResp.ID, "err", err)
-			httputil.WriteError(w, http.StatusInternalServerError, "storage error")
+			server.WriteError(w, http.StatusInternalServerError, "storage error")
 			return
 		}
 	}
 
 	resource := buildResponseResource(infResp, req.PreviousResponseID, req.ShouldStore(), req.Background, createdAt, &completedAt)
-	httputil.WriteJSON(w, http.StatusOK, resource)
+	server.WriteJSON(w, http.StatusOK, resource)
 }
 
 // HandleRetrieve handles GET /responses/{id}.
@@ -133,7 +133,7 @@ func (h *Handler) HandleRetrieve(w http.ResponseWriter, r *http.Request) {
 	var stored storedResponse
 	if err := json.Unmarshal(retrieved.ResponseBlob, &stored); err != nil {
 		h.log.Error("unmarshal stored response", "id", id, "err", err)
-		httputil.WriteError(w, http.StatusInternalServerError, "internal server error")
+		server.WriteError(w, http.StatusInternalServerError, "internal server error")
 		return
 	}
 
@@ -160,7 +160,7 @@ func (h *Handler) HandleRetrieve(w http.ResponseWriter, r *http.Request) {
 		Metadata:           map[string]string{},
 		ServiceTier:        "default",
 	}
-	httputil.WriteJSON(w, http.StatusOK, resource)
+	server.WriteJSON(w, http.StatusOK, resource)
 }
 
 // HandleDelete handles DELETE /responses/{id}.
@@ -181,10 +181,10 @@ func (h *Handler) HandleCompact(w http.ResponseWriter, r *http.Request) {
 	}
 	_ = json.NewDecoder(r.Body).Decode(&body)
 	if body.Model == "" {
-		httputil.WriteError(w, http.StatusBadRequest, "model is required")
+		server.WriteError(w, http.StatusBadRequest, "model is required")
 		return
 	}
-	httputil.WriteError(w, http.StatusNotImplemented, "compact not implemented")
+	server.WriteError(w, http.StatusNotImplemented, "compact not implemented")
 }
 
 // HandleListOrWS is implemented in ws.go.
@@ -196,17 +196,17 @@ func (h *Handler) HandleCompact(w http.ResponseWriter, r *http.Request) {
 func (h *Handler) mapCharonError(w http.ResponseWriter, err error, notFoundCode string) {
 	switch {
 	case errors.Is(err, charon.ErrNotFound):
-		httputil.WriteJSON(w, http.StatusNotFound, map[string]string{
+		server.WriteJSON(w, http.StatusNotFound, map[string]string{
 			"code":    notFoundCode,
 			"message": err.Error(),
 		})
 	case errors.Is(err, charon.ErrChainCorrupted):
-		httputil.WriteJSON(w, http.StatusConflict, map[string]string{
+		server.WriteJSON(w, http.StatusConflict, map[string]string{
 			"code":    "chain_corrupted",
 			"message": err.Error(),
 		})
 	default:
 		h.log.Error("charon error", "err", err)
-		httputil.WriteError(w, http.StatusInternalServerError, "internal server error")
+		server.WriteError(w, http.StatusInternalServerError, "internal server error")
 	}
 }

internal/inference/client_test.go → cmd/proxy/inference/client_test.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
 )
 
 var ctx = context.Background()

cmd/proxy/main.go

@@ -10,8 +10,8 @@ import (
 	"syscall"
 	"time"
 
-	"github.com/elevran/charon/internal/config"
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
+	"github.com/elevran/charon/internal/proxyconfig"
 	"github.com/elevran/charon/internal/server"
 	"github.com/elevran/charon/internal/telemetry"
 	"github.com/elevran/charon/pkg/charon"
@@ -26,7 +26,7 @@ func main() {
 func run() error {
 	log := slog.New(slog.NewJSONHandler(os.Stdout, nil))
 
-	opts := config.NewProxyOptions()
+	opts := proxyconfig.NewOptions()
 	fs := flag.NewFlagSet("proxy", flag.ExitOnError)
 	opts.AddFlags(fs)
 	_ = fs.Parse(os.Args[1:])

cmd/proxy/sse.go

@@ -7,8 +7,8 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/elevran/charon/internal/httputil"
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
+	"github.com/elevran/charon/internal/server"
 	"github.com/elevran/charon/pkg/charon"
 )
 
@@ -64,7 +64,7 @@ func (h *Handler) handleStream(w http.ResponseWriter, r *http.Request, req Creat
 
 	inputItems, err := inputToItems(req.Input)
 	if err != nil {
-		httputil.WriteError(w, http.StatusBadRequest, "invalid input")
+		server.WriteError(w, http.StatusBadRequest, "invalid input")
 		return
 	}
 
@@ -90,7 +90,7 @@ func (h *Handler) handleStream(w http.ResponseWriter, r *http.Request, req Creat
 	ch, err := h.inf.Stream(ctx, infMap)
 	if err != nil {
 		h.log.Error("inference stream", "err", err)
-		httputil.WriteError(w, http.StatusBadGateway, "inference error")
+		server.WriteError(w, http.StatusBadGateway, "inference error")
 		return
 	}
 

cmd/proxy/stateless_parity_test.go

@@ -28,7 +28,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
 )
 
 // capturedInfReq records a single request body received by the inference server.

cmd/proxy/testhelpers_test.go

@@ -21,9 +21,9 @@ import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/require"
 
+	"github.com/elevran/charon/cmd/proxy/inference"
 	"github.com/elevran/charon/internal/chainstore"
 	pebblebe "github.com/elevran/charon/internal/chainstore/pebble"
-	"github.com/elevran/charon/internal/inference"
 	"github.com/elevran/charon/internal/server"
 	"github.com/elevran/charon/pkg/charon"
 )

cmd/proxy/ws.go

@@ -9,11 +9,10 @@ import (
 	"sync"
 	"time"
 
-	"github.com/elevran/charon/internal/httputil"
-
 	"github.com/gorilla/websocket"
 
-	"github.com/elevran/charon/internal/inference"
+	"github.com/elevran/charon/cmd/proxy/inference"
+	"github.com/elevran/charon/internal/server"
 	"github.com/elevran/charon/pkg/charon"
 )
 
@@ -78,7 +77,7 @@ func (h *Handler) HandleListOrWS(w http.ResponseWriter, r *http.Request) {
 		h.HandleWebSocket(w, r)
 		return
 	}
-	httputil.WriteJSON(w, http.StatusOK, map[string]interface{}{
+	server.WriteJSON(w, http.StatusOK, map[string]interface{}{
 		"object":   "list",
 		"data":     []interface{}{},
 		"has_more": false,

internal/config/bytesize.go → internal/charonconfig/bytesize.go

@@ -1,4 +1,4 @@
-package config
+package charonconfig
 
 import (
 	"encoding/json"
@@ -19,14 +19,12 @@ var unitMultipliers = map[string]int64{
 }
 
 func (b *ByteSize) UnmarshalJSON(data []byte) error {
-	// Try plain number first.
 	var n int64
 	if err := json.Unmarshal(data, &n); err == nil {
 		*b = ByteSize(n)
 		return nil
 	}
 
-	// Try quoted string.
 	var s string
 	if err := json.Unmarshal(data, &s); err != nil {
 		return fmt.Errorf("bytesize: expected number or string, got %s", data)
@@ -35,7 +33,6 @@ func (b *ByteSize) UnmarshalJSON(data []byte) error {
 	s = strings.TrimSpace(s)
 	lower := strings.ToLower(s)
 
-	// Find where the digits end.
 	i := 0
 	for i < len(s) && (s[i] == '-' || s[i] == '+' || (s[i] >= '0' && s[i] <= '9')) {
 		i++