Go's //go:embed directive supports using glob mode to embed files or directories at compile time. 1. Match non-delimited characters in single-level directories, such as .txt to match txt files in the same directory; 2. Match any hierarchical path, including cross-directory recursion, such as templates//.html can contain html files in all subdirectories; 3. Multiple files can be embedded by spaces, such as assets/.png assets/.jpg; 4. Brace expansion (such as .{png,jpg}) is not supported, and each pattern needs to be explicitly listed; 5. The path is relative to the source file directory, and supports embedded in string, []byte or embed.FS types, and hidden files will also be included if matches. All matches are determined at compile time, so you need to ensure that the file exists.
Go's //go:embed
directive allows you to include files and directories directly in your Go binary at compile time. When using //go:embed
, you can specify glob patterns to match multiple files or directories in a concise way. These are called embedded glob patterns .

What Are Glob Patterns?
Glob patterns are simple string patterns used to match file paths. They're not as powerful as regular expressions, but they're easier to write and widely used in file matching (like in shells or build tools).
In Go's embed
context, glob patterns are used right after the //go:embed
comment to tell the compiler which files to include.

Supported Glob Patterns in //go:embed
Go uses the path.Match
function (from the path
package) to evaluate glob patterns. Here are the key pattern features:
-
*
— Matches any sequence of non-separator characters (ie, doesn't match/
).- Example:
*.txt
matchesreadme.txt
but notdocs/readme.txt
.
- Example:
-
?
— Matches any single non-separator character. -
[abc]
— Matches any one of the characters inside the brackets. -
**
— Matches any sequence of characters including path separators (ie, it can cross directory boundaries).- This is not part of standard
path.Match
, but Go'sembed
does support ` ``** in a special way when needed for recursive matching.
- This is not part of standard
-
/
— Literal path separator (use forward slashes even on Windows).
Common Use Cases and Examples
? Match all .txt
files in a directory
//go:embed config/*.txt var configFiles embedded.FS
This includes config/app.txt
, config/db.txt
, but not config/subdir/info.txt
.

? Match files recursively with **
//go:embed templates/**.html var templateFiles embedded.FS
This includes:
-
templates/home.html
-
templates/users/index.html
-
templates/admin/settings.html
The **
allows matching across subdirectories.
? Embed an entire directory tree
//go:embed static/* var staticFiles embedded.FS
Includes all direct children in static/
, but not nested files deeply if using single *
.
To include everything recursively:
//go:embed static/** var staticFiles embedded.FS
? Match multiple file types
You can embed multiple patterns by separating them with spaces:
//go:embed docs/*.md assets/*.png config/*.json var content embedded.FS
You can also use comma-separated patterns inside curly braces (brace expansion), though that's handled by the shell or tooling — Go itself doesn't expand braces. So this won't work:
//go:embed assets/*.{png,jpg} // ? Not supported directly
Instead, list them separately:
//go:embed assets/*.png assets/*.jpg var images embedded.FS
Important Notes
- Paths are relative to the directory of the Go source file containing the
//go:embed
directive. - You can embed into:
-
string
or[]byte
(for single files) -
embed.FS
(for multiple files or directories)
-
-
**
is supported only in the context of//go:embed
— it's a special extension Go adds for recursive file inclusion. - Hidden files (like
.gitignore
) are included if they match the pattern. - The glob matching is done at compile time , so it only sees files present then.
Summary
Go embedded glob patterns let you specify which files to include in your binary using simple pattern matching. Key patterns:
-
*
→ matches within one directory level -
**
→ matches recursively across directories (special support inembed
) - Multiple patterns → separate by space
- No brace expansion → write full patterns
They're not full regex, but sufficient for most embedding needs — just keep paths clear and test with small examples.
Basically: use *
for flat matches, **
for deep ones, and combine patterns as needed.
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