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@arianvp
arianvp / SSH_MACOS_SECURE_ENCLAVES.md
Last active December 11, 2025 16:27
Native Secure Enclaved backed ssh keys on MacOS

Native Secure Enclave backed ssh keys on MacOS

It turns out that MacOS Tahoe can generate and use secure-enclave backed SSH keys! This replaces projects like https://github.com/maxgoedjen/secretive

There is a shared library /usr/lib/ssh-keychain.dylib that traditionally has been used to add smartcard support to ssh by implementing PKCS11Provider interface. However since recently it also implements SecurityKeyProivder which supports loading keys directly from the secure enclave! SecurityKeyProvider is what is normally used to talk to FIDO2 devices (e.g. libfido2 can be used to talk to your Yubikey). However you can now use it to talk to your Secure Enclave instead!

@ample-samples
ample-samples / dot-product.lua
Last active December 11, 2025 09:58
Get the dot product of any MxN matrices
-- Utility functions for matrix.dot
local function dotScalar1dVector(scalar, v1)
local outputVector = {}
for i = 1, #v1, 1 do
outputVector[i] = v1[i] * scalar
end
return matrix(outputVector)
end
local function dotScalar2dVector(scalar, v1)
@sancar
sancar / README.md
Last active May 15, 2025 11:13
An upgradable read write lock for go

And upgradable read write lock for go

UpgradableRWMutex is an enhanced version of the standard sync.RWMutex. It has the all methods sync.RWMutex with exact same semantics. It gives more methods to give upgradable-read feature.

The new semantics for upgradable-read are as follows:

  • Multiple goroutines can get read-lock together with a single upgradable-read-lock.
  • Only one goroutine can have a write-lock and no read-lock/upgradable-read-lock can be acquired in this state.
@kconner
kconner / macOS Internals.md
Last active November 6, 2025 09:43
macOS Internals

macOS Internals

Understand your Mac and iPhone more deeply by tracing the evolution of Mac OS X from prelease to Swift. John Siracusa delivers the details.

Starting Points

How to use this gist

You've got two main options:

@tgross
tgross / vmctl
Created July 27, 2021 19:27
Fircracker virtual machine control script
#!/usr/bin/env bash
set -euo pipefail
help() {
cat <<EOF
vmctl [COMMAND] [ARGS]
Launch firecracker VMs from configuration templates with networks
managed by CNI. VM configuration is stored in $VM_CONFIG_DIR
and network configuration is stored in $NET_CONFIG_DIR
@thibaultcha
thibaultcha / README.md
Last active September 9, 2020 18:07
Align Nginx variables declarations with Vim

The Nginx code style asks for a specific alignment of variables declarations that is strainuous to manually enforce:

size_t                    slen;
uint32_t                  hash;
ngx_int_t                 rc;
const u_char             *p;
ngx_shm_zone_t           *shm_zone;
ngx_slab_pool_t          *shpool;
ngx_rbtree_node_t        *node, *sentinel;
ngx_ssl_session_t *sess;
#include "stdafx.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <uv.h>
#define DEFAULT_PORT 7000
#define DEFAULT_BACKLOG 128
@everilae
everilae / sqlite_json.py
Last active April 4, 2020 02:24
Hacky JSON support for SQLAlchemy SQLite dialect, if https://www.sqlite.org/json1.html extension is available.
from sqlalchemy.ext.compiler import compiles
from sqlalchemy.dialects import plugins
from sqlalchemy.dialects.mysql.json import JSONIndexType, JSONPathType
from sqlalchemy.engine import CreateEnginePlugin
from sqlalchemy.sql.elements import BinaryExpression
from sqlalchemy.sql import sqltypes
from sqlalchemy.sql.operators import \
json_getitem_op, \
json_path_getitem_op
@AtulKsol
AtulKsol / db_backup_commands.md
Last active December 28, 2024 02:23
Commands to backup & restore database
  1. pg_dump is a nifty utility designed to output a series of SQL statements that describes the schema and data of your database. You can control what goes into your backup by using additional flags.
    Backup: pg_dump -h localhost -p 5432 -U postgres -d mydb > backup.sql

    Restore: psql -h localhost -p 5432 -U postgres -d mydb < backup.sql

    -h is for host.
    -p is for port.
    -U is for username.
    -d is for database.