I'm a firm believer that certain kinds of music can be productively energizing for episodes of concentrated creativity, such as  programmers and software engineers may need to exert over extended stretches of time.  I was already a believer decades before the notion was popularly promoted among Baby Boomers (possibly mostly as an anecdotal claim) that classical music, esp. baroque, boosted the mental development of their technologically delayed offspring.

I compiled an initial list today of classical music that might also qualify as "relaxing" (alphabetical by surname):
· J.S. Bach: Brandenburg Concertos (i.e.: Nr. 1--6).
· J.S. Bach: Well-Tempered Clavier (i.e.: Prelude & Fugue Nr. 1--24).
· L. van Beethoven: Sym. Nr. 6 "Pastorale".
· William Boyce[†]: Sym. Nr. 1--8.
· Georg Friedrich Händel: "Water Music" and "Music for Fireworks".
· (Franz Josef Haydn: I'm mystified that my initial compilation lists none of his works).
· (Wolfgang Amadeus Mozart: I don't have specific works to recommend right now, but there are some concertos and 41 symphonies from which to choose).
· Modest Mussorgsky: Pictures at an Exhibition (originally piano-only, but orchestrated by Maurice Ravel, never mind partial orchestration by Emerson, Lake, and Palmer).
· Bedřich Smetana: Vltava (i.e.: "The Moldau").
· Antonio Vivaldi: The Four Seasons (i.e.: Concertos Nr. 1--4).

Other music that contains passages that fail description as "relaxing" could easily qualify as productively energizing for programmers and software engineers under the (marketing) label "classical thunder".  Perhaps that's best reserved for a separate topic (then again, perhaps it would fit best right here).

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Note †: Boyce was an unjustifiably obscure native Londoner musician, whose baroque compositions (fl. 1736--ob. 1779), if I can believe a single sample of CD-liner notes, were most commonly compared favorably to those of Händel.  Boyce's symphonies (esp. Nr. 1--4) are really well suited for the wee hours during which it's counterproductive or otherwise undesirable to awaken other family members.  Except that this classical-music  amateur cautions that listeners might want to crank up Nr. 5 (and Mvt. 1 of Nr. 6, 7, 8 [×]) as rather triumphal [‡].  Wey-all Haaay-deees!  How could I've forgotten how goood  these are?  Why did I neglect playing these CDs for so long?

Note ‡: O.K., not as triumphal as the grandly long Overture for Händel's Music for Fireworks, nor quite a lot of his Water Music.

Note ×: Why the [expletives deleted] is a sunglassed blue smiley being persistently displayed in note '†' when all I want is to display the ASCII digit '8', that being the digit following '6' and '7', followed by an ordinary right parenthesis?   Yes, I'll soon be requesting an answer about this inexplicable & unacceptable behavior by SMF.   "Bug" would not be too harsh a word at all.

Yes the Brandenberg Concertos would be on my list.

Perhaps try the 'Fantasia on Greensleeves' album by Vaughn Williams and further. Has 'The Lark Ascending' 'Five Variants on Dives and Lazarus' etc.

And as I suggested elsewhere too Toshiyuki Watanabe's 'Paused Wind' album with 'Falling Snow' etc.