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@sevkin
sevkin / url_open.go
Last active March 7, 2026 15:44
golang open url in default browser
// https://stackoverflow.com/questions/39320371/how-start-web-server-to-open-page-in-browser-in-golang
// open opens the specified URL in the default browser of the user.
func open(url string) error {
var cmd string
var args []string
switch runtime.GOOS {
case "windows":
cmd = "cmd"
args = []string{"/c", "start"}
@jboner
jboner / latency.txt
Last active March 7, 2026 06:39
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@staltz
staltz / introrx.md
Last active March 6, 2026 15:36
The introduction to Reactive Programming you've been missing
@tedmiston
tedmiston / nodejs-tcp-example.js
Last active March 5, 2026 23:45
Node.js TCP client and server example
/*
In the node.js intro tutorial (http://nodejs.org/), they show a basic tcp
server, but for some reason omit a client connecting to it. I added an
example at the bottom.
Save the following server in example.js:
*/
var net = require('net');

FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.


Effective Engineer - Notes

What's an Effective Engineer?

@paulirish
paulirish / bling.js
Last active February 27, 2026 04:33
bling dot js
/* bling.js */
window.$ = document.querySelector.bind(document);
window.$$ = document.querySelectorAll.bind(document);
Node.prototype.on = window.on = function(name, fn) { this.addEventListener(name, fn); };
NodeList.prototype.__proto__ = Array.prototype;
NodeList.prototype.on = function(name, fn) { this.forEach((elem) => elem.on(name, fn)); };
@rgreenjr
rgreenjr / postgres_queries_and_commands.sql
Last active February 23, 2026 13:47
Useful PostgreSQL Queries and Commands
-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
FROM pg_stat_activity
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc;
-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'
@dopiaza
dopiaza / slackpost
Created September 5, 2013 12:33
Post a message to a Slack channel
#!/bin/bash
# Usage: slackpost <token> <channel> <message>
# Enter the name of your slack host here - the thing that appears in your URL:
# https://slackhost.slack.com/
slackhost=PUT_YOUR_HOST_HERE
token=$1
@fntlnz
fntlnz / self-signed-certificate-with-custom-ca.md
Last active February 21, 2026 19:42
Self Signed Certificate with Custom Root CA

Create Root CA (Done once)

Last update: Nov 2025.

Create Root Key

Attention: this is the key used to sign the certificate requests, anyone holding this can sign certificates on your behalf. So keep it in a safe place!

openssl ecparam -genkey -name secp384r1 | openssl ec -aes256 -out rootCA.key