diff --git a/internal/installerconf/installerconf.go b/internal/installerconf/installerconf.go
index 30c6a3f..fc575f4 100644
--- a/internal/installerconf/installerconf.go
+++ b/internal/installerconf/installerconf.go
@@ -3,9 +3,46 @@
 // The format is simple key=value, one per line. Blank lines and lines
 // starting with # are ignored. Keys and values are trimmed of whitespace.
 //
+// Minimal example (covers ~60% of packages):
+//
+//	source = github
+//	owner = sharkdp
+//	repo = bat
+//
+// With version prefix stripping (jq tags are "jq-1.7.1"):
+//
+//	source = github
+//	owner = jqlang
+//	repo = jq
+//	version_prefix = jq-
+//
+// With filename exclusions (hugo publishes _extended_ variants):
+//
 //	source = github
 //	owner = gohugoio
 //	repo = hugo
+//	exclude = _extended_, Linux-64bit
+//
+// Monorepo with tag prefix:
+//
+//	source = github
+//	owner = therootcompany
+//	repo = golib
+//	tag_prefix = tools/monorel/
+//
+// Non-GitHub sources:
+//
+//	source = nodedist
+//	url = https://nodejs.org/download/release
+//
+//	source = gitea
+//	base_url = https://gitea.com
+//	owner = xorm
+//	repo = xorm
+//
+// Complex packages that need custom logic beyond what the classifier
+// auto-detects (e.g. ollama's universal binaries, ffmpeg's non-standard
+// naming) should put that logic in Go code, not in the config.
 package installerconf
 
 import (
@@ -15,9 +52,38 @@ import (
 	"strings"
 )
 
-// Conf holds the parsed contents of a releases.conf file.
+// Conf holds the parsed per-package release configuration.
 type Conf struct {
-	m map[string]string
+	// Source is the fetch source type: "github", "gitea", "gitlab",
+	// "gittag", "nodedist", etc.
+	Source string
+
+	// Owner is the repository owner (org or user).
+	Owner string
+
+	// Repo is the repository name.
+	Repo string
+
+	// BaseURL is a custom base URL for non-GitHub sources
+	// (e.g. a Gitea instance or nodedist index URL).
+	BaseURL string
+
+	// TagPrefix filters releases in monorepos. Only tags starting with
+	// this prefix are included, and the prefix is stripped from the
+	// version string. Example: "tools/monorel/"
+	TagPrefix string
+
+	// VersionPrefix is stripped from version strings.
+	// Example: jq tags as "jq-1.7.1" → set to "jq-" to get "1.7.1".
+	VersionPrefix string
+
+	// Exclude lists filename substrings to filter out.
+	// Assets whose name contains any of these are skipped.
+	// Example: ["_extended_", "-gogit-", "-docs-"]
+	Exclude []string
+
+	// Extra holds any unrecognized keys for forward compatibility.
+	Extra map[string]string
 }
 
 // Read parses a releases.conf file.
@@ -28,7 +94,7 @@ func Read(path string) (*Conf, error) {
 	}
 	defer f.Close()
 
-	c := &Conf{m: make(map[string]string)}
+	raw := make(map[string]string)
 	scanner := bufio.NewScanner(f)
 	for scanner.Scan() {
 		line := strings.TrimSpace(scanner.Text())
@@ -39,20 +105,49 @@ func Read(path string) (*Conf, error) {
 		if !ok {
 			continue
 		}
-		c.m[strings.TrimSpace(key)] = strings.TrimSpace(val)
+		raw[strings.TrimSpace(key)] = strings.TrimSpace(val)
 	}
 	if err := scanner.Err(); err != nil {
 		return nil, fmt.Errorf("installerconf: read %s: %w", path, err)
 	}
+
+	c := &Conf{}
+	c.Source = raw["source"]
+	c.Owner = raw["owner"]
+	c.Repo = raw["repo"]
+	c.TagPrefix = raw["tag_prefix"]
+	c.VersionPrefix = raw["version_prefix"]
+
+	if v := raw["base_url"]; v != "" {
+		c.BaseURL = v
+	} else {
+		c.BaseURL = raw["url"]
+	}
+
+	if v := raw["exclude"]; v != "" {
+		for _, p := range strings.Split(v, ",") {
+			p = strings.TrimSpace(p)
+			if p != "" {
+				c.Exclude = append(c.Exclude, p)
+			}
+		}
+	}
+
+	// Collect unrecognized keys.
+	known := map[string]bool{
+		"source": true, "owner": true, "repo": true,
+		"base_url": true, "url": true,
+		"tag_prefix": true, "version_prefix": true,
+		"exclude": true,
+	}
+	for k, v := range raw {
+		if !known[k] {
+			if c.Extra == nil {
+				c.Extra = make(map[string]string)
+			}
+			c.Extra[k] = v
+		}
+	}
+
 	return c, nil
 }
-
-// Get returns the value for a key, or "" if not set.
-func (c *Conf) Get(key string) string {
-	return c.m[key]
-}
-
-// Source returns the fetch source type (e.g. "github", "nodedist", "gitea").
-func (c *Conf) Source() string {
-	return c.m["source"]
-}
diff --git a/internal/installerconf/installerconf_test.go b/internal/installerconf/installerconf_test.go
index 13b8289..8e48fb8 100644
--- a/internal/installerconf/installerconf_test.go
+++ b/internal/installerconf/installerconf_test.go
@@ -8,106 +8,128 @@ import (
 	"github.com/webinstall/webi-installers/internal/installerconf"
 )
 
-func TestRead(t *testing.T) {
-	dir := t.TempDir()
-	path := filepath.Join(dir, "releases.conf")
-	os.WriteFile(path, []byte(`
-# Hugo release config
+func TestSimpleGitHub(t *testing.T) {
+	c := confFromString(t, `
+source = github
+owner = sharkdp
+repo = bat
+`)
+	assertEqual(t, "Source", c.Source, "github")
+	assertEqual(t, "Owner", c.Owner, "sharkdp")
+	assertEqual(t, "Repo", c.Repo, "bat")
+	assertEqual(t, "TagPrefix", c.TagPrefix, "")
+	assertEqual(t, "VersionPrefix", c.VersionPrefix, "")
+
+	if len(c.Exclude) != 0 {
+		t.Errorf("Exclude = %v, want empty", c.Exclude)
+	}
+}
+
+func TestVersionPrefix(t *testing.T) {
+	c := confFromString(t, `
+source = github
+owner = jqlang
+repo = jq
+version_prefix = jq-
+`)
+	assertEqual(t, "VersionPrefix", c.VersionPrefix, "jq-")
+}
+
+func TestExclude(t *testing.T) {
+	c := confFromString(t, `
 source = github
 owner = gohugoio
 repo = hugo
-`), 0o644)
-
-	c, err := installerconf.Read(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if c.Source() != "github" {
-		t.Errorf("Source() = %q, want github", c.Source())
-	}
-	if c.Get("owner") != "gohugoio" {
-		t.Errorf("owner = %q, want gohugoio", c.Get("owner"))
-	}
-	if c.Get("repo") != "hugo" {
-		t.Errorf("repo = %q, want hugo", c.Get("repo"))
+exclude = _extended_, Linux-64bit
+`)
+	if len(c.Exclude) != 2 {
+		t.Fatalf("Exclude has %d items, want 2: %v", len(c.Exclude), c.Exclude)
 	}
+	assertEqual(t, "Exclude[0]", c.Exclude[0], "_extended_")
+	assertEqual(t, "Exclude[1]", c.Exclude[1], "Linux-64bit")
 }
 
-func TestReadMonorepo(t *testing.T) {
-	dir := t.TempDir()
-	path := filepath.Join(dir, "releases.conf")
-	os.WriteFile(path, []byte(`source = github
+func TestMonorepoTagPrefix(t *testing.T) {
+	c := confFromString(t, `
+source = github
 owner = therootcompany
 repo = golib
 tag_prefix = tools/monorel/
-`), 0o644)
-
-	c, err := installerconf.Read(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if c.Get("tag_prefix") != "tools/monorel/" {
-		t.Errorf("tag_prefix = %q", c.Get("tag_prefix"))
-	}
+`)
+	assertEqual(t, "TagPrefix", c.TagPrefix, "tools/monorel/")
 }
 
-func TestReadNodeDist(t *testing.T) {
-	dir := t.TempDir()
-	path := filepath.Join(dir, "releases.conf")
-	os.WriteFile(path, []byte(`source = nodedist
+func TestNodeDist(t *testing.T) {
+	c := confFromString(t, `
+source = nodedist
 url = https://nodejs.org/download/release
-`), 0o644)
-
-	c, err := installerconf.Read(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if c.Source() != "nodedist" {
-		t.Errorf("Source() = %q, want nodedist", c.Source())
-	}
-	if c.Get("url") != "https://nodejs.org/download/release" {
-		t.Errorf("url = %q", c.Get("url"))
-	}
+`)
+	assertEqual(t, "Source", c.Source, "nodedist")
+	assertEqual(t, "BaseURL", c.BaseURL, "https://nodejs.org/download/release")
 }
 
-func TestReadSkipsBlanksAndComments(t *testing.T) {
-	dir := t.TempDir()
-	path := filepath.Join(dir, "releases.conf")
-	os.WriteFile(path, []byte(`
-# comment
+func TestGiteaBaseURL(t *testing.T) {
+	c := confFromString(t, `
+source = gitea
+base_url = https://gitea.com
+owner = xorm
+repo = xorm
+`)
+	assertEqual(t, "Source", c.Source, "gitea")
+	assertEqual(t, "BaseURL", c.BaseURL, "https://gitea.com")
+	assertEqual(t, "Owner", c.Owner, "xorm")
+}
+
+func TestBlanksAndComments(t *testing.T) {
+	c := confFromString(t, `
+# Hugo config
 source = github
 
-# another comment
+# owner line
 owner = foo
-`), 0o644)
+`)
+	assertEqual(t, "Source", c.Source, "github")
+	assertEqual(t, "Owner", c.Owner, "foo")
+}
 
-	c, err := installerconf.Read(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if c.Source() != "github" {
-		t.Errorf("Source() = %q", c.Source())
-	}
-	if c.Get("owner") != "foo" {
-		t.Errorf("owner = %q", c.Get("owner"))
+func TestExtraKeys(t *testing.T) {
+	c := confFromString(t, `
+source = github
+owner = foo
+repo = bar
+custom_thing = hello
+`)
+	if c.Extra == nil || c.Extra["custom_thing"] != "hello" {
+		t.Errorf("Extra[custom_thing] = %q, want hello", c.Extra["custom_thing"])
 	}
 }
 
-func TestGetMissing(t *testing.T) {
+func TestEmptyExclude(t *testing.T) {
+	c := confFromString(t, "source = github\n")
+	if c.Exclude != nil {
+		t.Errorf("Exclude = %v, want nil", c.Exclude)
+	}
+}
+
+// helpers
+
+func confFromString(t *testing.T, content string) *installerconf.Conf {
+	t.Helper()
 	dir := t.TempDir()
 	path := filepath.Join(dir, "releases.conf")
-	os.WriteFile(path, []byte("source = github\n"), 0o644)
-
+	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
+		t.Fatal(err)
+	}
 	c, err := installerconf.Read(path)
 	if err != nil {
 		t.Fatal(err)
 	}
+	return c
+}
 
-	if c.Get("nonexistent") != "" {
-		t.Errorf("Get(nonexistent) = %q, want empty", c.Get("nonexistent"))
+func assertEqual(t *testing.T, name, got, want string) {
+	t.Helper()
+	if got != want {
+		t.Errorf("%s = %q, want %q", name, got, want)
 	}
 }