diff --git a/internal/imports/mkstdlib.go b/internal/imports/mkstdlib.go
index bbdd1cd2d8e..85fbc2808aa 100644
--- a/internal/imports/mkstdlib.go
+++ b/internal/imports/mkstdlib.go
@@ -61,6 +61,7 @@ func main() {
 		mustOpen(api("go1.12.txt")),
 		mustOpen(api("go1.13.txt")),
 		mustOpen(api("go1.14.txt")),
+		mustOpen(api("go1.15.txt")),
 
 		// The API of the syscall/js package needs to be computed explicitly,
 		// because it's not included in the GOROOT/api/go1.*.txt files at this time.
diff --git a/internal/imports/zstdlib.go b/internal/imports/zstdlib.go
index 16252111ff2..7b573b9830b 100644
--- a/internal/imports/zstdlib.go
+++ b/internal/imports/zstdlib.go
@@ -56,6 +56,7 @@ var stdlib = map[string][]string{
 	},
 	"bufio": []string{
 		"ErrAdvanceTooFar",
+		"ErrBadReadCount",
 		"ErrBufferFull",
 		"ErrFinalToken",
 		"ErrInvalidUnreadByte",
@@ -303,7 +304,9 @@ var stdlib = map[string][]string{
 		"PrivateKey",
 		"PublicKey",
 		"Sign",
+		"SignASN1",
 		"Verify",
+		"VerifyASN1",
 	},
 	"crypto/ed25519": []string{
 		"GenerateKey",
@@ -322,11 +325,13 @@ var stdlib = map[string][]string{
 		"CurveParams",
 		"GenerateKey",
 		"Marshal",
+		"MarshalCompressed",
 		"P224",
 		"P256",
 		"P384",
 		"P521",
 		"Unmarshal",
+		"UnmarshalCompressed",
 	},
 	"crypto/hmac": []string{
 		"Equal",
@@ -432,6 +437,7 @@ var stdlib = map[string][]string{
 		"CurveP521",
 		"Dial",
 		"DialWithDialer",
+		"Dialer",
 		"ECDSAWithP256AndSHA256",
 		"ECDSAWithP384AndSHA384",
 		"ECDSAWithP521AndSHA512",
@@ -507,6 +513,7 @@ var stdlib = map[string][]string{
 		"ConstraintViolationError",
 		"CreateCertificate",
 		"CreateCertificateRequest",
+		"CreateRevocationList",
 		"DSA",
 		"DSAWithSHA1",
 		"DSAWithSHA256",
@@ -581,6 +588,7 @@ var stdlib = map[string][]string{
 		"PublicKeyAlgorithm",
 		"PureEd25519",
 		"RSA",
+		"RevocationList",
 		"SHA1WithRSA",
 		"SHA256WithRSA",
 		"SHA256WithRSAPSS",
@@ -694,6 +702,7 @@ var stdlib = map[string][]string{
 		"String",
 		"Tx",
 		"TxOptions",
+		"Validator",
 		"Value",
 		"ValueConverter",
 		"Valuer",
@@ -2349,6 +2358,27 @@ var stdlib = map[string][]string{
 		"IMAGE_DIRECTORY_ENTRY_RESOURCE",
 		"IMAGE_DIRECTORY_ENTRY_SECURITY",
 		"IMAGE_DIRECTORY_ENTRY_TLS",
+		"IMAGE_DLLCHARACTERISTICS_APPCONTAINER",
+		"IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE",
+		"IMAGE_DLLCHARACTERISTICS_FORCE_INTEGRITY",
+		"IMAGE_DLLCHARACTERISTICS_GUARD_CF",
+		"IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA",
+		"IMAGE_DLLCHARACTERISTICS_NO_BIND",
+		"IMAGE_DLLCHARACTERISTICS_NO_ISOLATION",
+		"IMAGE_DLLCHARACTERISTICS_NO_SEH",
+		"IMAGE_DLLCHARACTERISTICS_NX_COMPAT",
+		"IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE",
+		"IMAGE_DLLCHARACTERISTICS_WDM_DRIVER",
+		"IMAGE_FILE_32BIT_MACHINE",
+		"IMAGE_FILE_AGGRESIVE_WS_TRIM",
+		"IMAGE_FILE_BYTES_REVERSED_HI",
+		"IMAGE_FILE_BYTES_REVERSED_LO",
+		"IMAGE_FILE_DEBUG_STRIPPED",
+		"IMAGE_FILE_DLL",
+		"IMAGE_FILE_EXECUTABLE_IMAGE",
+		"IMAGE_FILE_LARGE_ADDRESS_AWARE",
+		"IMAGE_FILE_LINE_NUMS_STRIPPED",
+		"IMAGE_FILE_LOCAL_SYMS_STRIPPED",
 		"IMAGE_FILE_MACHINE_AM33",
 		"IMAGE_FILE_MACHINE_AMD64",
 		"IMAGE_FILE_MACHINE_ARM",
@@ -2371,6 +2401,25 @@ var stdlib = map[string][]string{
 		"IMAGE_FILE_MACHINE_THUMB",
 		"IMAGE_FILE_MACHINE_UNKNOWN",
 		"IMAGE_FILE_MACHINE_WCEMIPSV2",
+		"IMAGE_FILE_NET_RUN_FROM_SWAP",
+		"IMAGE_FILE_RELOCS_STRIPPED",
+		"IMAGE_FILE_REMOVABLE_RUN_FROM_SWAP",
+		"IMAGE_FILE_SYSTEM",
+		"IMAGE_FILE_UP_SYSTEM_ONLY",
+		"IMAGE_SUBSYSTEM_EFI_APPLICATION",
+		"IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER",
+		"IMAGE_SUBSYSTEM_EFI_ROM",
+		"IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER",
+		"IMAGE_SUBSYSTEM_NATIVE",
+		"IMAGE_SUBSYSTEM_NATIVE_WINDOWS",
+		"IMAGE_SUBSYSTEM_OS2_CUI",
+		"IMAGE_SUBSYSTEM_POSIX_CUI",
+		"IMAGE_SUBSYSTEM_UNKNOWN",
+		"IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION",
+		"IMAGE_SUBSYSTEM_WINDOWS_CE_GUI",
+		"IMAGE_SUBSYSTEM_WINDOWS_CUI",
+		"IMAGE_SUBSYSTEM_WINDOWS_GUI",
+		"IMAGE_SUBSYSTEM_XBOX",
 		"ImportDirectory",
 		"NewFile",
 		"Open",
@@ -4188,6 +4237,7 @@ var stdlib = map[string][]string{
 		"DevNull",
 		"Environ",
 		"ErrClosed",
+		"ErrDeadlineExceeded",
 		"ErrExist",
 		"ErrInvalid",
 		"ErrNoDeadline",
@@ -4646,6 +4696,7 @@ var stdlib = map[string][]string{
 		"ErrRange",
 		"ErrSyntax",
 		"FormatBool",
+		"FormatComplex",
 		"FormatFloat",
 		"FormatInt",
 		"FormatUint",
@@ -4655,6 +4706,7 @@ var stdlib = map[string][]string{
 		"Itoa",
 		"NumError",
 		"ParseBool",
+		"ParseComplex",
 		"ParseFloat",
 		"ParseInt",
 		"ParseUint",