Brad Lucas

Programming, Clojure and other interests

Multiple Geth Instances Warning

August 19, 2017

A point to remember when developing using geth locally. If you end up with multiple geth instances running you will get confused. Here I was running a geth instance in the background under screen. Today, not remembering it was there I started testrpc and then got the following error.

Error: Error: could not unlock signer account

So as a suggestion do a ps aux | grep geth once in a while.

Continue reading →


August 18, 2017

Ran across this article the other day.

"Inside the world of Silicon Valley's 'coasters' — the millionaire engineers who get paid gobs of money and barely work"

What I found myself thinking about after reading it was an experience I had at a company where they had setup a similar situation after buying a startup. But, in this case the situation was different in an important way. The company put the startup people in charge of their own group and told them to run it. The acquiring company didn't put one of their own in charge. They just assumed the startup would work within the larger company without any strong tie back into the buyer.

Continue reading →

Send Eth From Geth Console

August 17, 2017

A log of a session showing how to check account balances and then send ETH. In this example I'm running a geth console on a local node and I want to send 10 ETH to two different accounts.

First, I list the accounts and then see how much ETH I have in the default account.

> personal.listAccounts

> web3.fromWei(eth.getBalance(eth.coinbase)); 

Before attempting to send I need to unlock the account. This prompts you for your password.

Continue reading →

Org Mode Copy Just Headers

August 16, 2017

A tip for working with org-mode. The situation is where you have a large outline but want to extract just the headers. Say you want to expand only two levels and want to extract only those headers.

The key is org-copy-visible.

Expand your tree so you only see what you want to extract. Then select the tree and execute org-copy-visible (C-c C-x v).

Then paste the extracted headers somewhere else.

Continue reading →


August 15, 2017

Installed this interesting application on my laptop and a few other machines. It is called f.flux and it is an app that reduces the blue light in monitors in the evening. This is to prevent the stimulation that the blue light causes which ultimately effects your sleep.

So far I can say that in the evening with the new setup which has a soft orange-ish light is soothing.

The app has a very clever feature. You tell it when you typically wake up and then while you are working late it gently reminds you that you are waking up in 7 hours or some such number. A nice reminder not to over do it.

Continue reading →